Why Soil Prep and Plant Maintenance Matter

If you have ever wondered about whether soil preparation was really critical, or if that was just an “in a perfect world” condition, let me share my personal experiences. This spring, I started a new planting bed in an area that had been compacted by construction equipment. In some areas, I carefully dug and amended before planting. Other areas (I got tired and impatient), I just chiseled holes in the sticky red clay of upstate SC and plopped in seedlings. Thankfully, the holes of shrubs and perennials were all loosened and amended. The annuals did not receive the same care because, well, they are annuals.

Here are three examples demonstrating the difference that soil preparation can make. I have not fertilized the plants in these photographs.

Seedlings of the puny trio of Melampodium on the left were placed into unprepared soil three months ago. The trio on the right was installed in loosened and amended soil. They are twenty-two inches tall. These plants came from the same package of seed, were installed the same day, and are only a few feet apart, so they get the same sun exposure.

These Gomphrena seedlings were started from the same seed pack and placed in the ground the same day, three months ago. The plant on the left was placed into unprepared soil. It is five inches tall. The plant on the right was placed into soil amended with a shovelful of soil conditioner. It is twenty-two inches tall. These plants are in the same bed, a few feet apart.

Just like the examples above, these Zinnias were started from the same seed pack and seedlings were planted out the same day, only a few feet apart. The one on the left, placed in unamended soil, is a single stem, four inches in height. The one on the right, planted into amended soil, is well-branched and fifteen inches tall. I feel guilty every time I see the runts.

The final photograph, below, shows what happens when maintenance is ignored. Certain tall plants are prone to “spraddling” later in the season, especially after a hard rain. In early spring, I tip-pruned my Mexican Salvia and Joe Pye Weed. They branched obligingly, and are about two-thirds the height they would have been without the cutback. Joe Pye flowers are starting to open, and the Mexican Salvia will flower in another six weeks or so. I neglected to cut back the Brown-Eyed Susans (Rudbeckia triloba) and last week a thunderstorm took the flowers to the ground, where they remained. I was forced to cut plants back to about a foot. They will recover and produce a few late flowers, but I lost the exuberant show and strong stems that an early cutback would have produced.

These Brown-Eyed Susans were forty inches tall, in full bloom. Then the rain came, and down they went.

The message of this blog: Take whatever time is necessary to properly prepare soil before installing plants. Heavy clay can be improved with soil conditioner, compost, or leaf mold. When you backfill the holes with amended soil, just firm it by hand enough to ensure good root-to-soil contact. There is no need to stamp it like you are angry with Mother Earth. Plant roots need oxygen to thrive.

"Lite" Choices: Perlite vs Vermiculite

The large bag should last a long time.

I finally broke down and bought the mother of all bags of horticultural vermiculite. A whopping four cubic feet, it filled the entire back seat of my small car. In past years, I have purchased standard-sized bags found in home improvement garden centers or big box stores. During the coronavirus pandemic, the product was scarce. I had to make do by recycling media that had already been used for rooting or using smaller containers.

I do a lot of home propagation because I’m too cheap to buy full-size plants at the nursery. Vermiculite is my product of choice when it comes to propagation from cuttings. (If you want the complete details, please see my YouTube channel on small-scale home propagation using a Forsyth pot: https://www.youtube.com/watch?v=KsBv12O17MY ). The supersize bag should last a couple of years. Why don’t I use perlite instead, which is available at most garden centers? Are perlite and vermiculite interchangeable? Well, yes and no. Let’s compare these two products.

Perlite is volcanic rock which has been crushed and then heated until it explodes like popcorn. The small, rounded particles look like particles of Styrofoam, but it is unrelated. Styrofoam is manufactured from a petroleum-based product, styrene. Perlite is a renewable resource, assuming that earth’s volcanoes will continue to erupt. It is added to potting soils to make them more porous and can be mixed into heavy soils to reduce compaction. It is neutral to slightly alkaline in pH, odorless, non-toxic, won’t mold, and is easy to handle. It will retain approximately three times its weight in water. While it contains no fertility in its original state, I have noticed several bags that indicate a fertilizer has been added. Perlite is an ideal product for cactus or succulents, usually mixed with some form of potting soil or coir, a replacement for peat moss.

Perlite particles are evident in potting soil.

The downside of perlite, and the reason I avoid it, it that it is so light that it floats. If you have purchased six-packs of annuals grown in a soil mix that contains perlite, I’m sure you have seen what happens when those little plants are installed in flower beds or containers. After rain or irrigation, the white particles float to the top. I find those ghost-white balls unsightly and unnatural looking. That is a personal opinion, so feel free to differ.

Vermiculite is (get ready for a mouthful) magnesium aluminum iron silicate. It is 100% natural, and looks like someone threw a handful of mica into a blender. The product comes in fine, medium, or coarse textures. I prefer the fine-to-medium size, but again, that is personal preference. Vermiculite has a neutral pH. It retains both water and fertility. Mixed into heavy clay soil, it will make the soil more porous and less prone to compaction. I start each new growing season by dumping my propagation pots into my garden beds and mixing it in with the soil. If you plan to use it to lighten clay soil, the coarse grade works best.

Vermiculite retains more water than perlite, so it is preferred when the cuttings or potted plants need a bit more moisture. Perlite drains so quickly that it is not ideal for plants with high water demands.

When I asked a professional propagator his preference, he said that he uses a perlite/peat mix for cutting propagation and vermiculite for seed starting. I’m transitioning away from peat moss use, but a perlite/coir combination should work well. At seed-starting time, especially when starting tiny seeds like begonia, petunia or the like, I place the seeds on top of sopping wet vermiculite, then sprinkle with the very lightest application of dry vermiculite. I only bottom-water, to avoid displacing the seeds. Emerging seedlings have little problem in pushing their way through to sunlight.

Fig Season is Here

Fig season is approaching in the Snoddy garden. I grew up eating fresh figs, and as an adult was surprised to find that not everyone loves them. The sweet, gritty flesh is an acquired taste, like coffee, dates, olives, or beer. For some, the flavor is fine but the texture is unpleasant.

Figs are nutritional powerhouses, containing fiber, antioxidants, minerals, vitamins. Figs consist of 55% natural sugar, making them one of the sweetest fruits available. They can be eaten fresh or dried, plain, stuffed with cream cheese and drizzled with honey, or wrapped in bacon and baked. Figs makes a great canned jam, or they can be combined with raspberries, oranges, and grapes to make FROG jam.

The unique thing about the common fig (Ficus carica) is that what we think of as the fruit is actually the flower. The yellow, green, or purple mature fruits are what is called an “enclosed inflorescence” because the male and female flower grow inside what we consider to be the skin or peel, also called an infructescence. Figs are one of the few fruits that can develop without external pollination (“parthenogenesis”).  A type of wasp enters the fruit through a tiny hole at the base of the infructescense, pollinates the fruit and dies. These entryways are easily seen on the ripe fruit, opposite the stem. The fig interior contains an enzyme called ficain that dissolves and absorbs the wasp, so you aren’t munching on a wasp cadaver as you eat one. Some types of commercial figs have been bred to develop without pollination. If the wasp thing freaks you out too much, buy packaged fruit marked “California figs” or packages that indicate the fruit was raised without insect pollination.

Grow figs in full sun to part sun, in neutral to acidic soil. For best results, plant is humus-rich soil that is moist but well-drained. The plants are tolerant of neglect once established, but light pruning in winter can force the formation of new branches. Fruits are borne on new growth, so a cutback increases fruit yield. With time, plants can become too dense, so prune out a few of the oldest stems each year to increase air circulation. Figs are cold hardy in zones 7-10. Plant them in a protected area in the coolest parts of zone 7. Plants are easy to propagate from cuttings.

Figs are self-fruitful, so you only need one to have a crop. Be aware that these shrubs can grow quite large – thirty feet or so, and up to ten feet wide. Figs live a long time, usually thirty years or more. In my part of the southern US, most home plants are one of three varieties: Celeste, Brown Turkey, or LSU Purple. These have purple to brown fruit. If you decide to try one in your home landscape, consult your Extension agent to determine which varieties do best in your particular zone.

The small hairs on fig’s leaves can cause itching, so wear long sleeves when harvesting. Avoid the milky sap, too, as this can cause skin problems for some people. Don’t feed figs to dogs, cats, or horses. Be aware that birds and varmints will harvest some of the fruit for you. You can drape smaller shrubs with netting to exclude birds, but this is more difficult once the shrubs gain size. I always leave mine undraped and just pay the critter tax of shared fruit.

The entry hole is evident at the bottom of this ripe fruit.

A cluster of unripe fruit. Fig leaves are large.

Small Gardens Mean Fewer Colors

To keep a small garden from looking chaotic, show restraint with the number of flower colors. Smallish gardens can look fabulous with only two colors. This is not to say only two types of plants. Yellow and purple flowers pair well and give the gardener a large number of choices. Repeating the same flower colors but using different sizes of blooms and leaf forms provides attractive contrasts. Because flowers bloom on their own timeline, the use of different plants with the same bloom shades will keep the garden colorful even if some of them are taking a blooming siesta.

For my own small courtyard garden, I decided all perennials and flowering shrubs would be in shades of yellow, coral, and purple. To lure pollinators, I included yellow goldenrod (Solidago) and brown-eyed Susans (Rudbeckia triloba) in the dryest area, and yellow rain lilies in the damp areas near the drainage catch basin. For coral shades, I used Drift roses (small, shrubby, lower maintenance than most roses), coral penstemons, a dwarf Red Hot Poker (Kniphofia ‘Poco Red’) which is more coral than red, and a couple unknown varieties of daylily. For the purples, I chose sterile, dwarf Pugster® butterfly bushes (Buddleia), purpleheart (Tradescantia), purple coneflowers (Echinacea purpurea), and lavender-flowered Society Garlic (Tulbaghia violacea). All these plants attract numerous butterflies and hummingbirds.

I wasn’t certain that the Cuphea ‘Candy Corn’ that I planted last year would overwinter, but they did and now the yellow and orange flowers look right at home between the corals and yellows. The Gaillardia ‘Spin Top Red’ I planted last fall is more red than coral, but it has bloomed so lavishly that it will remain. Several varieties of Calla lilies in the chosen colors have not begun flowering yet.

This being a first-year garden, there were a number of empty holes in the layout, so I started annuals from seed to fill in the gaps. Next year, those gaps will be smaller as the shrubs and perennials gain size. By year three, annual use will be at a minimum. For now, yellow Melampodium, coral Zinnia, coral Salvia, purple Gomphrena and purple Salvia are providing abundant color. These were chosen not only for their hues but because they flower like mad all summer long and require little in the way of maintenance, other than the occasional removal of spent flowers (Zinnia and Salvia).

My past gardens have never featured coral shades, but I’m loving this color in the new beds. Plans are underway to add peachy/coral shades of Yarrow, Alstroemeria, Lycoris (“Hurricane Lily”), and Chrysanthemum to extend the chosen color palette into autumn. I’m including a few photos of the coral plants.

Testing a Deer Repellant Method

I have been experimenting with ways to keep deer from eating my precious garden plants. Native wildlife habitats are being transformed into new housing developments to accommodate the tremendous population growth in the southeast. Sightings of deer, turkeys, raccoons, possums, bears, and skunks are becoming common, even in city locations. I live in a rural area, where the deer seem to believe that I have prepared a buffet for them. They have a pronounced appetite for my hydrangeas, daylilies, hostas, and sunflowers.

Fencing my acreage would be cost prohibitive. I have tried several repellant tactics that worked only for a week or two: human hair and stinky soap. The birds like the former. The nests in my birdhouses looked like dolls’ wigs. And the deer liked the latter. They gnawed on the bars of Irish Spring hanging in my precious fruit trees. I tried a motion-activated radio (they danced) and a motion-activated water sprinkler (they showered, using Irish Spring, I assume). I also tried the bad smelling deterrents based on pigs’ blood or coyote urine (gross!) and the bad tasting ones based on rotten eggs or hot peppers. These worked until diluted by rain, but smelled so rank that I couldn’t tolerate their use. I refuse to reapply expensive products after every rain, so I have planted strong-fragranced plants like rosemary, society garlic, chives, and catnip throughout my beds. This has been successful in some areas, not in others.

I am a Master Gardener, and only present science-based information, but I feel compelled to share the results of my current deer discouragement experiment involving Milorganite. Milorganite is a mild fertilizer (6-4-0, slow release), in the form of small gray pellets. It is a sterile product manufactured from dried, processed microbes used to break down the intake of the Milwaukee Metropolitan Sewer District. Don’t be squeamish: It is NOT dried poop. Click here to get the real story on what it is and how it is manufactured. It has a pronounced fragrance, but humans must be a few inches from the product to detect it. Milorganite is not labeled as a deer repellant, but many people recommend using it for this off-label purpose. I decided to give it a try. Like the repellants above, it needs to be reapplied after every rain to be effective.

Call me thrifty or call me lazy, but I decided to develop a means of keeping the product dry from rains or irrigation while still allowing the odor to permeate the protection area. I use small, plastic food storage containers (Amazon) with snap-on lids. I used a regular, hand-held hole puncher to make a series of odor-escape holes around the upper part of the container, filled the containers half-full of Milorganite, and snapped the lids on to make a waterproof “sachet.” I nestled the transparent containers near the base of my hydrangeas and under the leaves of my hostas, where they are almost invisible. Through rain and irrigation, the pellets inside the container remain dry. For eight weeks now, no deer have munched on my plants although I have seen several small herds walk by. I am labeling this experiment a success. I’ll update you, readers, if things change.

Chaos Gardening, a recent trend

I try to stay informed on current gardening trends, so when I heard the new-to-me term “chaos gardening” I went into sleuth mode. Chaos gardening has recently gone viral on TikTok. One site describes it thus: “… letting go of the strict rules that come along with gardening and letting mother nature do the work instead” and “a haphazard and laid-back approach to gardening in which rules and meticulous garden planning are thrown out the window.”

Condensed version: Gather seeds packets, mix them together, and throw them on prepared (tilled, and raked if that is your choice) soil without a plan. Just writing that last sentence made me uncomfortable. I like plants to be arranged in groups of threes or fives, growing into each other in a lush tapestry that is casual but meticulously planned. A random jumble might sound romantic and low maintenance, but tall plants will shade out the shorter ones. Aggressive plants will overtake their delicate neighbors. Weeding will be difficult in the garden’s early stages, because desired plants cannot be distinguished from the undesirables. Seeds vary in their proper planting depths, so some may perish if they are sown too deep or too shallowly. And some seeds need light to germinate, while others need darkness. The advocates of chaos gardening always say, “some seeds won’t come up, and that’s okay.” Maybe for others, but not for me.

I start scrutinizing seed catalogs in late winter, planning new color schemes and flower bed expansions. I allow my imagination to run wild but I reel it in before ordering. By mid-spring, my catalogs are dog-eared and well worn from being thumbed through frequently. Some folks have elegant coffee-table books. My version is the current Baker Creek’s The Whole Seed Catalog, 532 colored pages of luscious heirlooms and recipes that makes me consider turning one of our pastures into a food plot. Then the temporary insanity fades and I return to a more restrained approach. My seed choices are intentional, purposeful, and not part of a random mix.

Chaos gardening is not the same as guerilla gardening, where one spreads seeds onto property they don’t own, like vacant lots or public areas. The intent is to beautify waste places or provide pollinator habitat. Don’t mistake chaos gardening for cottage gardening, either. Cottage gardens may be an informal mixture of annuals, perennials, grasses, herbs, and edibles but they are carefully planned, not random.

If the idea of chaos gardening appeals to you, start with a small area first and select seeds that germinate easily, have similar light requirements, and are not overly aggressive in their growth habits: cosmos, zinnias, marigolds, echinacea, celosia are good for sunny areas. Keep notes of what you sow so that you have an idea of what is emerging. Send me photos of your successes!

Proven Perennial Selections

Thanks to pleasantly warm temperatures and plentiful rains, my garden is thriving right now. So are the weeds, meaning that much of my outdoor time is spent in uprooting little monsters before they become big monsters.

Recently, I have received numerous inquiries from new gardeners, asking for plant recommendations. Every one of these gardeners has told me that they want to plant perennials only and no annuals. I get it. Annuals need to be replaced yearly, a recurring expense and effort. Yet, gardens benefit from the additional of a few annuals to add a lush appearance while the perennials are becoming established. Annuals tend to bloom throughout the season, while most perennials have a short flowering window. In my opinion, the most attractive gardens have it all: trees, shrubs, perennials, annuals, bulbs, vines, groundcovers.

If you are one of those who adamantly insist on perennials to the exclusion of all else, I am listing the Perennial Plant Association’s “Plant of the Year” winners for the last 27 years. Select from this list as you design your garden and you are likely to have a good experience. Finicky perennials don’t land here. I’ve killed a couple of the other featured plants (2020 and 2018), and removed a couple I didn’t cherish (2015, 2008, 1995). I am growing 2019’s Betony for the first time, and I am loving it so far. It is covered with pollinating insects from dawn to dusk.

2024 Phlox paniculata 'Jeana' (phlox)
2023 Rudbeckia ‘American Gold Rush’ (black-eyed Susan)
2022 Schizachyrium scoparium (little blue stem)
2021 Clinopodium nepeta subsp. nepeta Calamint
2020 Aralia cordata 'Sun King' Japanese spikenard 
2019 Stachys monieri 'Hummelo' Betony
2018 Allium ‘Millenium’ (ornamental onion)
2017 Asclepias tuberosa (butterfly milkweed)
2016 Anemone x hybrida ‘Honorine Jobert’ (windflower)
2015 Geranium ‘Biokova’ (dwarf cranesbill, hardy geranium)
2014 Panicum virgatum ‘Northwind’ (tall switch grass)
2013 Polygonatum odoratum var. variegatum (Solomon’s seal)
2012 Brunnera macrophylla ‘Jack Frost’ (Siberian bugloss)
2011 Amsonia hubrichtii (blue star)
2010 Baptisia australis (blue false indigo)
2009 Hakonechloa macra, ‘Aureola’ (Japanese forest grass)
2008 Geranium ‘Rozanne’ (cranesbill, hardy geranium)
2007 Nepeta racemosa ‘Walker’s Low’ (catmint)
2006 Dianthus ‘Firewitch’ (cheddar pink)
2005 Helleborus x hybridus (Lenten rose)
2004 Athyrium niponicum var. pictum (Japanese painted fern)
2003 Leucanthemum x superbum ‘Becky’ (shasta daisy)
2002 Phlox paniculata ‘David’ (tall phlox)
2001 Calamagrostis x acutiflora ‘Karl Foerster’ (feather reed grass)
2000 Scabiosa ‘Butterfly Blue’ (pincushion flower)
1999 Rudbeckia fulgida var. sullivantii ‘Goldsturm’ (black-eyed Susan)
1998 Echinacea purpurea ‘Magnus’ (purple coneflower)
1997 Salvia x sylvestris ‘Mainacht’ (aka ‘May Night’) (wood sage)
1996 Penstemon digitalis ‘Husker’s Red’ (beardtongue)
1995 Perovskia atriplicifolia (Russian sage)
1994 Astilbe ‘Sprite’ (dwarf astilbe)
1993 Veronica ‘Sunny Border Blue’ (speedwell)
1992 Coreopsis verticillata ‘Moonbeam’ (threadleaf coreopsis)
1991 Heuchera micrantha var. diversifolia ‘Palace Purple’ (coral bells)
1990 Phlox stolonifera (creeping phlox)

Bumblebees LOVE the purple, bottlebrush flowers. Early in the morning, I find several fat bumblebees who have fallen asleep which visiting the flowers.

This trio of Stachys monieri ‘Hummelo’ sits next to a deck. The purple flowers have strong stems and the bright green foliage brightens the area.

Garden Fencing for Privacy and Safety

Why fence your garden? As population growth booms in the southeast, so does the need for housing. Many modern developments of single-family, standalone homes in our corner of the world feature smaller lots than in past decades, putting neighbors closer to each other than before. No matter how fond we are of our neighbors, sometimes we feel the need for more privacy. Homeowners Association Covenants usually have specific rules on height, type, and placement of fencing. Even those that prohibit “front yard” fencing usually are more lenient in back yards.

Back yard fencing can benefit the gardener in several ways. It provides a visual backdrop against which plants take center stage as distracting views of the neighbors’ yards are blocked. It can also offer security. As the old adage states, “out of sight, out of mind,” so solid fencing can help reduce theft of garden furniture, art, containers, or even plants by hampering views of your valuables from passersby.

Fencing helps in preventing the neighborhood children or pets from accidentally trampling our prized specimens. It won’t deter squirrels and raccoons from visiting, but may help with preventing hungry rabbits from sampling your tasty plants. While jumping deer can easily clear most standard-height fences, they generally do not jump into an area they cannot see into. Since deer are creatures of habit, disrupting their regular travel paths with fences can redirect them away from the garden.

Fences give the gardener privacy from viewers. I don’t mind someone observing me relaxing in a lawn chair with a cold beverage while I enjoy watching the hummingbirds and butterflies in my garden, but I’m self-conscious when a surprise visitor catches me wearing mismatched clothing with muddy knees as I water and weed, usually in a most unflattering, bottoms-up posture. I don’t dress to impress in the garden – I just grab whatever is atop the pile of clean laundry. It tends to be the same baggy sweats and floppy t-shirts, over and over. Near the completion of our recent renovation project, I learned that the construction crew members who didn’t remember my name called me Mrs. Red Sweatpants.

Select fence materials that suit the style of your home. Rustic homes look comfortable with rustic fences, while more formal architecture looks right with iron or PVC fences. Keep in mind that all types will need maintenance sooner or later. Leave enough space between plants and fence so that you will have access for painting, staining, or cleaning.

Rather than growing vines directly on fences, I recommend that you position a trellis near and parallel to the fence. Secure the trellis to the fence (nylon tie-wraps are my preferred anchor) to prevent tilting. When fence access is needed, remove the anchor or cut the tie-wrap and tilt the trellis away from the fence until the maintenance is complete, then resecure the trellis to the fence. Done properly, this can be done with no damage to the vine.

Containers can be mounted directly on fences, adding another dimension or beauty. Keep in mind that elevated containers will need frequent watering in hot weather, and that water will eventually cause damage to wooden fences.

An unsung benefit of fencing is the extra level of weather protection it provides, blocking harsh winds. A tightly spaced development retains more heat in winter. Often that degree or two of warmth makes it possible to grow tender plants that might die in more exposed locations.

One critical item to consider: all fencing should have at least one gate so that the enclosed area can be accessed by lawn equipment. A double-width gate makes vehicular entry possible. This may not seem important initially, but when it is time to spread fresh mulch, you will appreciate the ability to spread directly from a truck or trailer rather than pushing mulch or new plants into the secured area one wheelbarrow at a time.

Nasturtiums peek through an open-weave fence

An open slat fence pairs with shrubs to offer as much privacy as a solid stockade fence.

Fencing can save delicate plants from rowdy pups.

Hellebore Black Death Disease (Virus)

Lenten Rose or Hellebore is one of the easiest, most reliable groundcovers for shade gardens and woodlands. So, I was surprised to receive three inquiries in the past month about dead or dying plants, with pinched stems and black-spotted leaves. My first guess was boggy soil. We have enjoyed plentiful rains this spring, so clay soils in poorly drained areas may be swampy enough to encourage root rot. A little more digging, though, uncovered a new, previously unknown (to me) culprit:  the virus Helleborus Net Necrosis Virus (HeNNV), also known as Black Death.

The virus presents with blackened, stunted or deformed leaves and can include a strange netting pattern around the leaf veins. Young, tender growth is usually first to be affected. Stems and flowers can also show signs of the virus. One of the earliest signs is puckering of the leaf surface around the veins. Don’t confuse HeNNV with fungal diseases like Hellebore Leaf Spot, which presents with rounded red or brown spots on leaves, usually seen in autumn and treatable by removing the damaged leaves. HeNNV is viral, not treatable.

The New York Botanical Garden LuEsther T. Mertz Library has a great article on Hellebores. Here is what they say about the Net Necrosis Virus: “The black death virus has been observed in Europe since the early 1990’s. Studies of the disease by Washington State University, examining strains found in the United States, determined that this disease is a Carlavirus, a group of viruses transmitted by insects for which plants serve as hosts and distinct from any previously encountered viruses. The insect vector for this disease has been assessed to be the hellebore aphid, which proliferates on hellebores. Not all aphid species are able to transmit all viruses and other aphid species have not yet been demonstrated to transmit this disease. It is believed to be carried on the feeding parts (stylets) of aphids but is not internalized (non-persistent transmission), thus the disease is carried for a period no longer than a few minutes.

Because the virus is transmitted on the feeding parts of aphids, preventing feeding is the most promising management technique in nursery greenhouse settings. There are systemic insecticides that are licensed for these settings in some states. Use of insecticides on home gardens to deter aphids, however, would not be effective or practical as a very short-interval repeat of application in an open environment would be needed.” A photo of a virus-stricken plant is included with the article.

Strong-growing plants may show more resistance to the virus. Humus-rich, well-drained soil and good air circulation help keep plants healthy. I have read that a fertilizer heavy in potash, applied once or twice a year, will help keep Lenten Rose a rich, healthy green. I have not tested that myself nor have I read university research on this topic, so consider that as “maybe” information only. Potash is the K in NPK on fertilizer bags. Many fertilizers that are labeled specifically for tomatoes contain an elevated amount.

What do you do if you spot a troubled plant in your own garden? Dig it up, bag it, and send it out with the trash. Do not add diseased plants to the compost pile. If you catch the problem early, you may be able to prevent its spread to surrounding Hellebores.

Thus far, I have only developed one suggested alternative plant as a Hellebore replacement. That plant is Evergreen Solomon’s Seal, Disporopsis pernyi. Hardy in zones 6-9, it has arching stems that resemble a very short Leucothoe. It has tiny fragrant flowers in spring, spreads rapidly, and is deer resistant. While they are both in the Asparagaceae family, Evergreen Solomon’s Seal is not in the Polygonatum genus of deciduous Solomon’s Seals. If evergreen foliage is not important to you and your garden, please also consider Polygonatum humile, Dwarf Solomon’s Seal. It reaches nine inches in height and makes a lush groundcover in woodland areas, hardy in zones 5-9. I have ruled out Pachysandra as a good replacement (too slow, too temperamental) but Sweet Woodruff, Galium odoratum, is still under consideration.

Winter sun backlights this healthy Hellebore.

Stinkhorn Mushrooms Live Up to the Name

A crowd gathered in the garden of a friend recently. I assumed they were admiring a new plant, so I hustled over to share in the appreciation. But no, this was no new perennial. Emerging from the mulch was a group of orange finger-like growths wearing dark brown caps. Their slightly naughty appearance spurred a lot of jokes. When I bent down to take a closer look, the nasty odor caught me by surprise. My brain churned a minute until I was able to dredge up its proper identity: Stinkhorn Mushroom. There are several forms of the stinkhorn fungus, ranging from rounded to those in front of my group, shaped like something you would see for sale in the classified section of an adult magazine. Common names for stinkhorn mushroom include Devil’s Dipstick (my favorite), Demon Fingers, and Dog Stinkhorn.

Stinkhorn mushrooms grow on rotting wood – decaying stumps or mulch, for instance. They can be found across the US, usually after a period of damp weather, The dark cap on top of the horn is a slimy mass of reproductive spores. This is where the “stink” in stinkhorn arises. The smell is described as sewage-like or compared to rotting meat. Unlike a normal fungus whose spores are spread by wind, the stinkhorn’s brownish cap atop the pinkish-orange horn contains a gooey collection of spores. These spores hitch a ride on insects who spread them about. The stench helps lure pollinators (those with a warped sense of smell, I assume) such as flies, ants, beetles, or bees. Insects who consume this odd mushroom then excrete the spores to begin a new generation.

Despite their evil appearance, stinkhorns are not poisonous and they do not transmit diseases to plants. If they appear in your garden, please leave them alone. They should not be treated with antifungals or herbicides. They are excellent decomposers. They only feed on dead plant tissue, so do not pose any threat to live, healthy plants. Stinkhorns are short-lived and offer amusement to garden visitors. Just don’t stand down wind.

These stinkhorns made a surprise appearance in a friend’s garden, just in time for a garden club meeting.

Agapanthus or Lily-of-the-Nile for Containers or Ground

Agapanthus (pronounced ag-ah-PAN-thus) or Lily of The Nile makes me think of Allium, but the leaves are more substantial and the bloom appears more robust. Given a choice between the two, I would choose exotic-looking Agapanthus. I attempted to grow this plant many times in the past. My plants would last a year or two, and then would dwindle away or even die outright during a cold, wet winter. New cultivars are on the market now, with enhanced cold tolerance, so I am trying again. Some varieties are evergreen while others are deciduous. Check the label to know what you are buying.

Agapanthus is a fleshy rhizome that hails from South Africa. Another common name is African Lily. It prefers at least a half-day or sun or more. The labels indicate cold hardiness from zone 8 through 11. If you live in a cooler area, you can grow Agapanthus in containers and bring them indoors when winter arrives. Be careful to avoid overwatering in winter.

Most Agapanthus flowers are in shades of blue, but purple and white forms are available also. Individual leaves grow to three inches wide and 12 to 24 inches in length. Dwarf forms are available. The flowers are umbrels, clusters of individual flowers that appear as a single flower atop a sturdy stem. Each small flower has six petals; most have a darker stripe down the center of each petal. A fully opened flower is approximately the size of a tennis ball. This year, I paired a white cultivar with blue flushes (‘Indigo Frost’) with a white-flowered Mandevilla vine in a container with an added trellis.  I have high hopes for this combination. The Mandevilla has not started to climb its trellis yet, but I think it will be an ideal paring. Ultimately, the Mandevilla vine will serve as a windbreak and a visual backdrop for the Agapanthus flowers.

Agapanthus likes a well-drained, moist soil of neutral pH. It will not tolerate constantly wet soil. For best flowering, fertilize in early spring and again after flowering concludes.

Be patient with Agapanthus. It takes a year or two for it to reach its full potential. Rhizomes will enlarge and plants will spread over time. The seeds of spent flowers can be harvested and will germinate but it takes several years for seed-grown specimens to begin flowering. Propagation by division is a faster method. Plants bloom best when rootbound, so don’t be quick to separate. Use care when dividing ground-grown plants, as the thick feeder roots spread widely and shallowly. It is best to divide congested plants in autumn rather than spring.

Agapanthus leaves are toxic if eaten and the sap can cause skin irritation. This does not impact hummingbirds and other pollinators, who love visiting the blooms, but it deters nibbling from deer.

This newly planted pairing will be beautiful once the white-flower Mandevilla starts to cover the trellis.

The Sweet Scent of Summer Rain

My garden welcomed the recent rains after almost a week of dry weather. Along with the rain came that wonderful, earthy smell known as “petrichor.” This scent is noticeable when rain falls on dry soil. The smell comes from a combination of factors.

Texas A&M University described the main source of the odor thus: “The main contributor to petrichor are actinobacteria. These tiny microorganisms can be found in rural and urban areas as well as in marine environments. They decompose dead or decaying organic matter into simple chemical compounds which can then become nutrients for developing plants and other organisms. A byproduct of their activity is an organic compound called geosmin which contributes to the petrichor scent. Geosmin is a type of alcohol, like rubbing alcohol. Alcohol molecules tend to have a strong scent, but the complex chemical structure of geosmin makes it especially noticeable to people even at extremely low levels. Our noses can detect just a few parts of geosmin per trillion of air molecules.”

Plant oils are another contributor to the smell. Plant leaves secrete these oils almost like they are producing their own sunscreen, but the goal is to reduce moisture loss through transpiration. Rainfall rinses those oils into the soil and into the surrounding air. In a 2015 study, scientists used high speed photography to capture raindrops causing tiny particles to be ejected into the air. The technical term for this is “frenetic bubble generation.” MIT describes the process as similar to bubbles rising in a glass of champagne.

The scent of rain can also be enhanced by ozone resulting from lightning that occurs during summer thunderstorms.

The different factors combine to create a smell that people can detect – those of us with good sniffers, that is. My grandfather could always predict a rain before it started without the benefit of doppler data. Now, I settle into a comfortable porch chair when the rain starts, sip a glass of iced tea, and enjoy that sweet smell, Mother Nature’s perfume.

Keep Cast Iron Containers Cool

A traditional favorite gardening container material is cast iron. Cast iron urns are beautiful and elegant, but are very heavy. Painted cast aluminum is a popular substitute because it does not rust and it is not quite as weighty.

In the deep south, the walls of metal plant containers capture heat in summer. They transfer heat to the soil within, to the detriment of the plants growing within. One way to prevent hot metal from damaging tender roots is to provide an insulation layer between the pot and the potting soil. I have tried several different strategies. The most effective insulator I have found is bubble wrap, the kind used for protecting delicate items during shipping. It is inexpensive, flexible, and malleable to fit the nooks and crannies of elaborate containers. Simply cut a piece of wrap that is large enough to line the inside of the container. Place the wrap around the outside container walls, being careful to avoid blocking any drainage holes. It is easily trimmed to size with scissors, so that there is no excess visible above the soil line. Add regular potting soil inside the bubble wrap layer, and – voila! – the soil will not become scorching hot because it is not in direct contact with the metal. The thin material does not reduce the amount of soil available to whatever plants you choose for your container.

Another tidbit: Reduce the amount of potting soil needed by large containers by adding a layer of pine cones in the bottom, before adding soil.

This iron urn is lined with bubble wrap prior to the addition of potting soil.

A green and white combination looks classy and cool, even in the heat. Container contents: Diamond Snow Euphorbia (a filler), Rosemary (a thriller), and a double Calibrachoa (a second filler). Not shown, an ivy with a white leaf edge (a spiller). The Rosemary is evergreen, so it can carry over to anchor a winter container.

The completed planting. In a couple of weeks, the Rosemary will gain height and be a vertical center accent. The strong pine-like scent of Rosemary repels some insects. I’m hoping that it will keep mosquitos away from the seating area near this container, one of a matching pair.

Caladiums for Color in Shade

Caladium (pronounced ka-LAY-dee-um) is a genus of tubers grown for their colorful summer foliage. Heart-shaped leaves grow up to 15 inches long and 10 inches wide, in freckled or streaked shades of pink, white, rose, red, green, burgundy, and occasionally yellow.

Plants are perennial in zones 9 and warmer. Some gardeners opt to grow them as annuals. They look fabulous in shady beds or hanging baskets. They can also be grown as houseplants by those who enjoy a challenge. Caladiums prefer moist, acidic soil that is high in organic matter. They prefer shade or partial shade, and pair well with Begonia and Impatiens. Mature height is less than two feet, so situate them where they will not be blocked by taller plants.

Caladiums enjoy the same water needs as Hostas and ferns. Like Hosta, they are targets for damage by snails and slugs. Placing them in the same bed as Hostas makes it easier to restrict chemical use to a limited area. My favorite products to eliminate snails are Sluggo or Escar-Go. Both are iron phosphate products that are non-toxic to humans, pets, and fish. I’ve read mixed reviews on whether it is harmful to earthworms. If you want to check out this type of molluscicide (fancy word for slug-killer), be sure to append your search with “site:.edu” so that your results will be ONLY university-based research articles and not product advertisements or non-science based opinions.

Caladiums enjoy a fertile soil, but excess fertilizer will cause the new leaves to trend toward green instead of colorful variegations. Use a time-release fertilizer or monthly application of diluted liquid plant food.

Tubers, an irregular shape, are available in garden centers in early spring. Full size, pot-grown specimens are sold a few weeks later. Larger bulbs produce larger plants.

Caladiums refuse to grow until the soil has warmed to at least 70 degrees, so there is no point in planting them before May. Earlier planting may result in rot. The foliage makes a remarkably long-lasting addition to the cut-flower arrangement. While Caladiums do bloom occasionally, their flowers are barely noticeable. Remove the flowers (spadix) if desired to direct more energy to leaf growth.

The mostly-white types look smashing when paired with white Impatiens. Some of the most popular varieties are ‘Freida Hemple’ and ‘Fanny Munson.’ Others, ‘Rosebud,’ ‘Red Chief’ and ‘White Queen’ will tolerate more sun (3-4 hours) than most. Some cultivars feature a “strap leaf” form with narrower leaves or ruffled edges. If Caladium leaves begin to twist, it is a sign they are not happy with their location – either too much or too little water, or too much sun.

If you choose to store your tubers from year to year, prepare to lift them in autumn. When cool weather approaches, withhold water for a few days to help them enter a dormancy period. Lift the tubers before they are touched by frost. Allow them to dry a few days out of direct sun, brush off excess soil, then store them in peat moss or vermiculite until next year. It is difficult to determine which way is “up” with the dried tubers. The smooth side is the bottom. Plants will still sprout if planted upside down, but position them vertically (edge up) to play it safe.

While many bulbs need a period of cool weather to rest, Caladium is an exception.  The tubers’ storage temperature should never drop below 50 degrees, or they may not recover.  For most of us, this means keeping them inside the house rather than in an unheated garage or garden shed.  Just don’t forget where you put them (a sad personal experience).

All part of Caladium are toxic to humans and pets if eaten. The sap causes a rash for sensitive-skinned gardeners, so use caution if leaves are gathered for flower arrangements.

Additional cultural tidbit from our friends at Clemson Extension Home & Garden Information Center: “Each caladium tuber has a large central bud surrounded by several small buds. Most caladium varieties produce only a few colorful leaves when the prominent central bud is allowed to grow. Remove the central bud to allow the tuber to produce many more shoots and leaves. Use the tip of a sharp knife to lift out the large central bud, being careful not to injure any of the surrounding small buds.” (HGIC Factsheet 1160.)

Garden Sharing and Caring

My garden is located on the NC/SC state line, in a zone which has finally passed the date for last frost. I have been outdoors every day, planting seedlings and pulling weeds. No matter how hard I try, the weeds appear faster than I can remove them. Typically, I select one plant to research for this weekly blog, but yesterday as I rested in the shade, I looked around at the plants that moved with me to my current home. My landscape is not just a garden, it is a testimony of friendship. So, today’s topic is sharing.

Many gardeners have themed areas or outdoor rooms: Pollinator gardens, sensory gardens, moonlight gardens. I don’t have any of those. Instead, I have a Friendship Garden. When I see Blackberry Lily, I recall my friend Pam, now deceased. Hardy orchids remind me of Linda, Epimedium means Cindy, and Crinum lilies recall Neil, a generous customer from my days working in a nursery. Ginger Lily means Melissa, a Ginkgo ‘Saratoga’ says Barbara, yellow coneflowers whisper Janice, and the Hardy Begonia reminds me of Pat. Iris ensata testifies my friendship with Cathy. Shasta Daisies and Crystal Falls Ophiopogon tell of Jane’s generosity. So, so many others.

Everywhere I look, I see not just the plants but the dear friends who shared cuttings, seeds, or bulbs with me. Gardeners are generous people who enjoy sharing their successes and commiserate with failures. Only my closest friends did not question my sanity when I spray painted the dead spots in boxwoods (two shades of green for realism) before our home wedding reception. Those same friends volunteered labor when straight-line winds took down a tree and a storage building the week before a scheduled garden tour.

There is a rarely-mentioned benefit to sharing plants with your friends. If you lose a plant due to disease, insects, animals, or some other reason, you know a ready source for replacement cuttings, seeds, or bulbs. Sharing is one of the best ways to hedge one’s bets, and I encourage you to be generous when someone admires a plant featured in your landscape.

Sadly, there is a corollary to this advice. There is an emotion somewhere between rage and disappointment (rageppointment?) when one has shared a plant – a plant that you have nurtured from a tiny cutting, giving it love and care until it was large enough to rehome – only to learn that the recipient has allowed it to languish and die. I realize that life sometimes gets in the way, but if I have given you three beautiful Hostas and you tell me that they succumbed when you planted them in the baking sun next to your garage, don’t be surprised if I fail to offer you replacements. It is disheartening when I drive by your home and see one of my plant foster children sitting in the bone-dry zone next to your garage, unwatered and unloved, dead as the tag emerging from the lifeless dirt. My donations are easy to spot, because my labels are distinctive.

Please, if you accept a plant from another’s garden, commit to getting it in the ground where the sun exposure meets the plant’s needs. If you cannot do that in a timely manner, just tell the one making the offer that you don’t have the time right now, you cannot offer the plant what it needs, or it doesn’t fit in your color scheme. Honesty at this point increases your chances for another offer at a later date. Don’t accept a plant you do not want.

This row of petite, shade-tolerant Iris tectorum started as a single rhizome gift from a friend. I’ve divided them over and over, and now have a nice stand. I love the color.

Blue-Eyed Grass as Feature or Edger

While weeding in a community garden last week, I encountered a plant I had written about several years ago, Blue-Eyed Grass. I have not grown it in my home garden. One of its common names is Bermuda Blue-Eyed Grass. After battling common Bermuda (aka wiregrass) in my lawn and flower beds, I was not about to introduce any plant that shared the name or other characteristics. I’ve been keeping a watchful eye on the specimens in the community garden for two years now, and they appear to be well-mannered. While diminutive in size, their impact is powerful. It’s time to reconsider my initial wariness.

Blue-Eyed Grass is Sisyrinchium angustifolium, pronounced sis-ee-RINK-ee-um an-gus-tee-FOH-lee-um. The species name has changed several times, but the genus Sisyrinchium remains consistent. Blue-Eyed Grass is a semi-evergreen, clump-forming native found across most of the eastern half of the country, in zones 4-9. Plants are undemanding. They grow in any texture soil and partial shade to full sun, preferring a consistently moist soil and average fertility. Rich soil or too much fertilizer results in lush leaf growth and few flowers. Keep mulch away from the base of the plant to avoid root rot.

They can be used singly as a specimen or as an edging. When flowering is complete, trim the spent heads to prevent unwanted spread. Blue-Eyed Grass looks at home in rock gardens, cottage gardens, woodland gardens, and sloped gardens. Bees and butterflies love their pollen and nectar, so they work well in pollinator gardens as well.

Mature clumps of Blue-Eyed Grass can reach up to 16 inches, although 12 inches is more common. The blue flowers appear in spring and summer, and are held above the foliage. Like other members of the Iris family, clumps should be divided every year or two to keep them looking healthy. The cultivar ‘Lucerne’ has larger flowers than unnamed varieties.

Sisyrinchium angustifolium, Blue-Eyed Grass, used as a specimen in a community pocket park.

Turn Trash Into Treasure

I enjoy recycling ugly things into beautiful things, especially garden decorations. So, when I spotted four weathered concrete statues in a thrift store last year, my “fix it” alarm sounded. Below is the step-by-step transformation. Follow my steps on your own weathered piece to produce a passable imitation of bronze.

Here is the forlorn foursome, positioned in the rear of a thrift store and priced to sell.

The Four Seasons in concrete, found at a thrift store for a few dollars each

After transporting them home (ugh–heavy!), I used water and a stiff brush (kitchen dish brush for larger areas and toothbrush for tight places) to scrub them clean of years of pollen, dirt, and dead moss. Any deep cracks were filled with epoxy. While the concrete was still damp, I painted them with a coat of black satin latex paint thinned with a little water. I experimented with flat and semi-gloss paint, but preferred the satin sheen. For your projects, start painting at the bottom of the piece and work to the top. Paint the bottom first to prevent ground moisture from seeping into the concrete. Applying black base paint while the item is damp will encourage the porous texture of the concrete to absorb the pigment rather than the color just resting on the surface.

After a vigorous scrubbing

Once the black paint is dry, use gold acrylic craft paint to highlight the raised details of the statues. I tried several different versions of gold and found that a champagne tone produced more believable results than a brighter. yellowish tone. For best results, use a dry-brush technique: Use either a flat or round paintbrush. I prefer a flat chip brush. Squeeze a few drops of paint onto a flat surface. Barely dampen the paintbrush bristles with paint, and then remove almost all the paint by passing the bristles over a piece of cardboard (preferred) or paper towel. The goal is to have just enough paint to leave a hint of color. Use the almost-dry brush to touch the areas where light hits the sculpture, the outermost points. Go light. More highlighting can be added later, if you decide the item needs more. Once you are satisfied with the appearance, use a clear, satin latex aerosol spray to preserve the finish for outdoor use.

 Here are the Four Seasons, after spending a year outdoors. I think they appear as a passable imitation of bronze – at a bargain price.

Moss Phlox or Thrift Provides a Blanket of Spring Color

“Common” names often cause confusion about plant identity. The spring-flowering groundcover at my childhood home was always called Thrift. It wasn’t until I started working at a garden nursery that I learned that its true identity was Phlox subulata, pronounced FLOCKS sub-yoo-LAH-tah. Then a customer asked for Thrift but meant Armeria, also known as Thrift. The two Thrifts are completely unrelated. Armeria juniperifolia (juniper-leaved thrift) and Armeria maritima (sea thrift) grow up to one foot tall. One has sharp foliage like a juniper while the other has grassy-like foliage. Both are perennial in zones 4-9, and are salt-tolerant. Their flowers remind me of Scabiosa. The focus of today’s blog is Phlox subulata, an old-fashioned southern standby.

Phlox subulata is also known as Creeping Phlox, Moss Phlox, Rock Phlox, and Thrift. This evergreen perennial reaches only six inches tall, at most. It forms a tight mat of needle-like foliage that works well as a groundcover and is frequently used in combination with large rocks. The flowers are small (3/4 inch across, with five petals) but so numerous that they conceal the leaves, appearing like a blanket of color. Thrift is blooming right now in my area, with showy mats of pink, rose, white, light blue, or lavender flowers. It is often used on steep banks or slopes, where it will self-seed and spread to cover uneven terrain and prevent erosion. Give Thrift full sun or part sun in acidic soil. It requires little maintenance beyond a little thinning if it becomes so congested that it starts choking itself.

Phlox subulata is native to the US and will grow in zones 3-9. It is rarely bothered by insects or diseases. Deer do not normally browse Thrift; the flowers are favored by hummingbirds, bees, and butterflies.

I planted a couple of these Phlox subulata under a new redbud (Cercis chinensis ‘Don Egolf’) last year. The color of the flowers is a near-match to the color of the tree’s blooms. They flower at the same time, and are neighbors to a yellow Forsythia, which provides a nice color contrast.

This thick mat of Thrift (Phlox subulata) has spread to replace grasses or weeds that might have grown under this fence, eliminating hand-weeding or string-trimming.

Sassafras Signals Spring

Spring’s arrival in evident in the woodlands: the reddish tint of maple trees, the yellow-green of new leaves on others. From a distance, I spotted a haze of yellow that I assumed to be flowering Carolina Jessamine, the SC state flower. But no, it was the early flowers of Sassafras, pronounced SAS-ah-fras.

Sassafras is a deciduous native, found in more than half of the states, and is hardy in zones 4-9. It can be either a tree or a multi-stemmed shrub and will grow in neutral to acidic soil of almost any texture. It prefers full sun to partial sun. Flowers on female trees produce blue-black seeds held by red stems that are a favorite food of wildlife. Several species of swallowtail butterfly larvae feed on the leaves. Unfortunately, Japanese beetles eat them also. Fall leaf color is outstanding.

Established trees are heat and drought tolerant. Mature trees can reach to 60 feet tall and 40 feet wide. Trees can be pruned hard every other year to force multiple stem growth to create a hedge. Left alone, plants tend to sucker and may grow into a thicket naturally.

One of the most unusual facts about sassafras is that trees have three distinct leaf shapes, often occurring at the same time on a single plant. Leaves can be oval, mitten shaped (think of a palm with fingers held together and the thumb extended), or three-lobed (most common). Crushed leaves or injured bark exude a spicy scent. Native Americans used parts of the plants in medical treatments. Later, the roots were used to flavor root beer. That practice was discontinued when a cancer-causing compound was detected in the roots. You can still purchase filé, a thickening condiment made from powdered leaves, used in Cajun dishes like gumbo. The carcinogenic chemical concentration in filé is minimal.

Sassafras plants have a deep taproot that make them difficult to transplant unless they are small. The growth rate is medium to rapid. Avoid boggy sites to lessen the chance of root rot. Sassafras is in the laurel family and suffers from some of the same issues – leaf spot, wilt – that plague other laurels. These issues are unlikely to damage the plant. Plants may be attacked by the Redbay Ambrosia Beetle, an insect known to spread laurel wilt. Ambrosia beetle is easy to detect. It makes the trunk look like toothpicks are stuck into the bark. If you see this issue on Sassafras or any other tree, contact your local Extension office for advice on treatment or removal.

Press Pause on Planting

I have no self-restraint when it comes to starting seeds indoors. Every year I begin too early and then I’m faced with seedlings that need to be planted outdoors or risk the danger of them becoming rootbound in their starter trays. I study the average temperature charts and review weather projections like a professional meteorologist. I transplant too early, and inevitably face a late frost. Then, I scurry around with row covers, old sheets, milk jugs, carboard boxes, and anything else I can find to protect my precious babies. Does this sound familiar to you?

Please, follow my advice and not my example. Seed packages provide the length of time before germination occurs. Find your last frost date and count backwards to the proper seed starting date for your area. My best results come when transplants have at least two pairs of leaves, not counting the cotyledons (“seed leaves”). Planting out a few days late is far better than planting out a few days too early. Cold-nipped tender plants take time to recover, so there is no gain from a head start.

Seeds have a specific temperature range for germination, so if you direct sow outdoors before the soil has warmed, they will sit until the temperature is right. In worst cases, they rot and die instead of sprouting. To learn the first frost and last frost dates for your zip code, visit https://garden.org/apps/frost-dates/ . To determine the soil temperature for your zip code visit https://www.greencastonline.com/tools/soil-temperature . The USDA Cold Hardiness Zones were updated in 2023 to reflect current data. My zone changed from 7b to 8a. To check the zone of your garden, visit https://planthardiness.ars.usda.gov/ .

While we think of 32 degrees as the magic point, frost can occur at temperatures below 36 degrees. A light breeze and high humidity help prevent frost formation. Cold air sinks, so garden beds located at the lowest part of your property may be a few degrees cooler than higher points. But gardening on a hilltop has its own challenges. For every 1,000 feet of elevation increase, temperatures drop 3 to 5 degrees below the average forecast. Gardens located near your house can benefit from the stored heat radiated by sun-heated buildings.

Frost is most likely to occur when skies are clear and temperatures fall in the afternoon. Clouds act like a blanket, retaining the sun’s heat near the surface. If you need to cover plants, get those sheets or whatever in place before sundown to maximize the amount of heat trapped. And don’t forget to remove them. One year I lost every tomato plant in my garden because I left glass quart jars over them while I rushed off to the office. Yes, they made it through a frosty night fine but then cooked to death when the sun came out and heated them through the glass. If only I had waited.

I found these clear plastic domes (“cloches”) at one of those stores where everything is $1.25. They have an adjustable air vent at top and pre-made holes around the bottom lip so they can be secured in place with a couple of landscape staples. Not as elegant as the classy glass ones, but easier to store and definitely cheaper.