Amsonia - A Two-Season Star

Amsonia hubrichtii, (pronounced am-SO-nee-yuh hew-BRIK-tee-eye) is flowering right now. This Arkansas native’s soft blue flowers are held at the top of tall stems that waft gracefully on the breeze. Leaves are narrow, leading to the common name Threadleaf Blue Star. Its fine, feather-like texture contrasts well with broad-leaf perennials like Black-Eyes Susans or Coneflowers. It also looks pretty when planted next to burgundy foliage plants like Ninebark, Smokebush, or Loropetalum.

While the spring flowers are pretty, Amsonia’s best season is fall. Those narrow leaves turn a golden yellow that glows in sunlight. For maximum impact, pick a site where the late afternoon sun provides a backlight.

Amsonia is undemanding. Give it full sun or mostly sun and it will be happy in zones 5-8 . Too much shade or excess water will cause it to flop. In rich soil, it may grow so tall that it opens up in the center in late summer. It takes at least a year or two for Amsonia to reach its potential. Don’t pull it up prematurely. Mature plants will reach heights of three feet, with a equal spread. Prevent the flopping or center separation by pruning it back to a height of six inches immediately after flowering ends. Cut to ground level just before spring growth commences.

Amsonia hubrichtii was the Perennial Plant Association’s “Plant of the Year” in 2011. Amsonias look great planted in masses. Flowers attract butterflies, and deer don’t seem too interested.

The blue flowers of Amsonia float at the top of thread-like foliage.

This Amsonia is just beginning to show hints of fall. In a few weeks, it will be a mass of butter-yellow leaves.

Indian Hawthorn for Hedges, Flowers, Berries

Indian Hawthorn is one of the most popular landscape shrubs around. This dense evergreen makes a great hedge or foundation plant. It is hardy in zones 7-10. It will tolerate almost any garden soil (clay, loam, sand) as long as it is mildly acidic and not bone dry or constantly wet. Summer flowers are pink or white, and are followed by attractive clusters of small, deep blue or purple fruits. Pollinators love the flowers and birds flock to the berries. 

Plants naturally form rounded mounds. Mature height is up to 6 feet, so place it where it will not need constant pruning to fit into a small space. A few cultivars are larger, and can gain heights to 12 feet. When pruned severely, shrubs look like piles of sticks for several weeks. Installation or transplanting should be done in fall or winter. Hawthorns struggle when moved in hot weather. Grow in full sun in cooler zones, partial shade in warmer areas. New growth is bronze-green and is subject to damage by late cold snaps.

If Indian Hawthorn (Rhaphiolepis indica, pronounced raf-ee-oh-LEP-iss IN-dih-kuh) is healthy, it is beautiful. Unfortunately, its popularity has led to major overplanting. Place too many of any single type of plant in an area (think city-size, not your yard), and diseases and insects move in and create havoc. (Remember the Red Tip Photinia rage of several decades ago? They were planted in every neighborhood. Then a fungal leaf spot moved in, spread like mad, and bye-bye Red Tip hedges.) The cultivars ‘Eleanor Tabor,’ and ‘Snow White,’ are more disease-resistant than some. Soaker hoses or drip irrigation are preferable to overhead watering, since they keep foliage dry to discourage leaf spots.

Because Indian Hawthorn is a sturdy shrub, it is planted near parking areas and in shopping center medians. Full sun, excess heat, and insufficient irrigation lead to weakened plants that eventually fall prone to several insects and diseases, resulting in defoliation. In home landscape situations, Indian Hawthorns are frequently eaten by deer.

A close view of the lovely flowers of Indian Hawthorn. Note the beginning of leaf spot disease, left side.

This healthy hedge of Indian Hawthorn lives in a parking lot island of a big box store in upstate South Carolina.

A sad-looking hedge showing leaf loss.

The Tractor Seat Plant

“Tractor Seat Plant” is the descriptive common name of Farfugium japonicum. The variegated (yellow spots) form has the common name “Giant Leopard Plant.”

Farfugium (pronounced far-FEW-gee-um) is hardy in zones 7-9. The yellow flowers are incidental to the foliage, exotic-looking leaves so shiny that they appear polished. Plants are not picky as to soil acidity. They want partial shade and moist soil, and are ideally sited along streams or near water features. They also make impressive container plants if the gardener provides plentiful irrigation. The large rounded to kidney-shaped leaves wilt pitifully when they need water. Plants die to the ground in winter, then pop up in spring and bloom in late summer to fall before they go dormant again.

Opinions vary as to whether solid or variegated leaves are the prettiest. (I favor the solid green.) The clumps of foliage look especially good against a solid brick or rock wall. Give plants plenty of space. Mature plants may reach four feet tall, three feet across. Individual leaves may reach impressive widths of 18 inches, held aloft on 3–4-foot stalks that rise directly from the ground. Plants are propagated by division. ‘Bad Hair Day’ and ‘Crispatum’ cultivars have a ruffled edge to the leaves.

Farfugium is rarely troubled by disease or insects, although slugs sometimes attack. They are moderately deer resistant.

A young Farfugium,. When mature, it will shade the fairy statue like a large umbrella.
Photo by Suzanne Leone. Used with permission.

Silvery Artemisia Makes a Deer-Proof Companion

The silvery threads of Artemisia make other plants look better by contrast. It can also play peacemaker between flower colors that may clash. This perennial shrub is hardy in zones 6-9. It will grow to three feet in height, and up to four feet wide in its first season. Any limbs that touch soil may sprout roots, resulting in an increasing clump. It also spreads by rhizomes.

Like other plants with gray foliage, Artemisia (pronounced ar-tem-EE-zee-uh) is heat-tolerant and drought-tolerant but suffers from wet soils or high humidity. ‘Powis Castle’ cultivar is reputed to be more humidity-tolerant than others. It has a finely cut foliage that looks super when paired with needled evergreens or purple foliage (think Loropetalum or Purple Heart). Shrubs may have yellow blooms, but flowering is rare and doesn’t add much to the overall appearance. A newish cultivar, ‘Seafoam,’ has neat curlicue foliage. I plan to trial its humidity resistance in the Mary Snoddy garden as soon as I find it in a local nursery. Artemisia foliage can be dried and used for wreaths or in flower arrangements.

Personal experience taught me that this is a plant that thrives on neglect. Initially, I planted ‘Powis Castle’ in a partly sunny spot and watered it during hottest days. By the end of its first season, it looked tatty, not at all attractive. Year two was even worse – long stems with limited (brown, nasty) foliage. In frustration, I pulled it out of the ground, tossed it on the gravel pile next to my greenhouse, and forgot it. Imagine my surprise three weeks later, when I realized that it had returned from the brink of death and was thriving atop a hot, dry gravel pile. Lesson learned. I planted a pair of future purchases in horrible, red fill dirt on top of a slope and added no supplemental irrigation. They flourished.

‘Powis Castle’ will survive in any soil type, and prefers a neutral to alkaline soil. Mature plants may open up in the center and look rather rangy. Limited pruning can be done any time plants are actively growing. They withstand hard pruning and will regenerate into dense shrubs. Important: Do NOT prune in late fall or winter. Wait until active new growth starts in spring before whipping out the loppers. Plants pruned in winter are likely to die.

Artemisia is not grown for its pleasant fragrance. Crushed foliage or cut stems exude a strong smell. This odor is what makes deer avoid it. Plants are untroubled by insects or diseases.

You will notice that I have not provided a common name for Artemisia. Well, here goes: Wormwood.

Soft, fern-like foliage of Artemesia

Artemesia paired with Cryptomeria globosa ‘Nana’

I threw this Artemesia onto a gravel pile. Instead of dying, it became a robust, healthy plant. Here it shares space with Lambs Ears, a creeping Sedum, and Eucalyptus.

Pretty Pittosporum Shrubs

We have had some trees removed to open up a mountain view. As a result, there is a new design opportunity in the Mary Snoddy garden. The steeply sloped area, approximately four acres, has scattered tall hardwoods, a few native Dogwoods, patches of Mountain Laurel, numerous Sourwood trees, and rocks for days. Big rocks. My vision for the future includes a meandering  path with decorative plantings on either side, all the way down to the creek. The path will need switchbacks due to the steep slope. Opportunities abound for plants in full sun, full shade, and everything between.

My tree and shrub choices need to be hardy in zone 7 with a tolerance for rocky, acidic soil.  They also need to be tolerant of heat and humidity while being deer resistant (a relative term, for sure). I started my plant selection Wish List by scanning photos of other gardens I have visited and admired. From this, I gleaned a small set of shrubs and trees to research. One of these is Pittosporum tobira ‘Variegata.’ I can still remember the wonderful fragrance of this evergreen shrub, a variegated cultivar clad in gray-green leaves with white margins. The clusters of flowers open white but turn yellow when pollinated. The homeowner had allowed the shrub to grown unpruned. It was four feet tall and about the same width.

I learned several things about Pittosporum. First, I have been pronouncing the name incorrectly for decades. It’s not pit-oh-SPORE-um. The correct pronunciation is pih-TOSS-pur-um. It is cold hardy in zones 8-10, although cultivar ‘Mojo’ is more compact and a bit more cold-tolerant. ‘Wheeler’s Dwarf’ is even more compact but less cold-tolerant than others. Mature height for most cultivars is 8-10 feet.

Pittosporum is tough, fast-growing, demands well-drained soil, and makes a good evergreen hedge. It is not particularly choosy about light (full sun to partial shade) or soil acidity. It is resistant to salt, making it a good choice for coastal gardens.

Unfortunately, deer are attracted to Pittosporum and frequently browse it year-round. This trait and its borderline hardiness in my area moved it from my ‘Wish’ list to the ‘Not For Me’ list.

Pittosporum has an interesting characteristic known as ‘sympodial growth.’ This means that the terminal bud will stop growing and lateral buds will keep on growing, giving stems a zig-zag look. This constant forking is also seen in some orchids and Beech (Fagus) trees. For Pittosporum, the terminal bud usually ceases growth because a flower has formed at the tip.

To prevent leaf spots and fungus problems, provide good air circulation, avoid overhead watering, and remove fallen leaves. Note that Daconil®, a common fungicide, is not labeled for use on Pittosporum and will damage or kill the plant. Counter aphid attacks with spray-on horticultural oil.

Pittosporums are easy to propagate from cuttings taken in late summer. Use a talc-based rooting compound to increase success rate.

Clemson University has an excellent fact sheet: https://hgic.clemson.edu/factsheet/pittosporum/

Pittosporum in flower.

Photo by Jean-Pol GRANDMONT - Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=4561211

Proceed with Caution When Planting Horsetail Rush

Equisetum, commonly known as Horsetail or Scouring Rush, has an other-worldly look. There are no leaves. Stems are hollow and bright green, and have narrow horizontal, black joints that faintly resemble bamboo. Other common names include Bottlebrush, Foxtail, Pinetop, Snakegrass, and Dwarf Bamboo. Fossils of Equisetum show its existence 350 million years ago.

Like some bamboo, Equisetum is a serious spreader. It loves wet soil, even standing water up to four inches deep, but will also grow in dryer soils. Be certain that you want it in your garden, because it is impossible to eradicate once established. It will grow in zones 5-10 and under any light conditions: full sun to full shade. Plants put down deep roots (rhizomes up to six feet in length).

Equisetum (pronounced ek-wis-SEE-tum) does not flower. Unbranched stems, up to four feet in height, are either sterile or non-sterile (reproductive). Non-sterile stems have brown scales while the sterile stems have green or no scales. The reproductive stems produce spores on a cone. Stems contain silica, creating a tough, rough texture that was formerly used to scour cooking vessels, leading to the common name Scouring Rush.

This plant can be grown in a container to prevent its spread. It makes a striking pond-side plant and a dandy resting place for dragonflies. It is highly deer resistant.

A patch of Equisetum growing near a bog area.

The black horizontal bands around Equisetum stems.
Image by Annette Meyer from Pixabay

Spring Seed Starting

Seed starting season is upon us, and I’m receiving “how to” questions. I do not profess to be an expert, but I can share what has worked for me. Here is the Mary Snoddy methodology, refined over several decades of hand-on experience.

Start with high quality seeds. You can purchase new packages each year, or you can use leftovers from last year, as long as the seeds were stored in a cool, dark, dry place. Some seeds will last several years (tomatoes) while others get stale quickly and should be purchased fresh each year (lettuce, parsley). Starting your own seeds offers the benefit of many more choices than are available from transplants at local nurseries. And some plants (corn, beans) are more successful when started directly in the ground (“in situ”) than from transplants.

Most big box stores and garden supply stores sell seed starting containers, a waterproof tray that holds six or eight inserts, segregated into four or six sections. A complete kit may include a plastic snap-on lid or dome cover to create a humid environment. It is easy to recycle plastic trays from year to year (I reuse those from plants I purchased) but it is imperative that the recycled trays, dividers, and covers are clean. Before reusing old containers, I soak them for 30 minutes in a five-gallon bucket of bleach water (nine parts water to one part bleach), then rinse well and dry in the sun.

Reusing starter items without sterilizing them may introduce pathogens that will kill off your precious seedlings. It is heartbreaking to see a flat of new seedlings succumb, overnight it seems, to “damping off.” This condition results in stems looking like they have been pinched. Once the stem develops this thin, pinched-looking spot, there is no recovery. Remove the seedling and its soil as quickly as possible, to prevent fungal spores from spreading to healthy plants. Prevent damping off by using clean containers, avoiding overwatering, and providing good air circulation.

Use seed-starting medium instead of potting soil or garden soil. Bags of “seed starter mix” are widely available. This is a very fine, lightweight substance that allows seeds to emerge with minimum effort. It is most efficient to fill the prepared starter trays with pre-moistened starter mix. If the medium seems to shed water rather than absorbing it, either use hot water or add a drop of dishwashing detergent to the water used for dampening the mix. I prefer the hot water method, and usually dump a couple of cups of hot water directly into the bag and wait about 30 minutes for it to absorb, shaking the bag a few times for even distribution. Pack the damp media into the containers, plant seeds at the depth recommended on the package, mist lightly to ensure seeds get wet, and top with a light sprinkle of dry starter mix.

A few seeds need light to germinate, while others need total darkness. These seeds must be exposed to light in order to germinate: African Violet, Ageratum, Artemesia, Begonia, Bells of Ireland, Browallia, Chinese Lanterns, Coleus, Coreopsis (Tickseed), Dusty Miller, Aquilegia (Columbine), Gaillardia, Geranium, Heuchera (Coral Bell), Impatiens, Lychnis (Lamb’s Ears), Nicotiana, Penstemon, Pentas, Petunia, Platycodon (Balloon flower),  Poppies, Portulaca, Primrose, Snapdragon.

The following seeds need darkness to germinate: (Don’t confuse germination with seedling growth. ALL seedlings need light to grow. Insufficient light will result in spindly, weak plants.) Armeria, Calendula, Catharanthus (Periwinkle), Centaurea, Delphinium, Echinacea (Coneflower), Gazania, Nasturtium, Tithonia (Mexican Sunflower).    

Warm temperatures make seeds germinate. Soil heating mats or cables are available in nurseries that sell seed starting supplies. These work great, but there is no need to get fancy like. I have had excellent success by repurposing a couple of old electric heating pads (the kind used for soothing sore muscles). Just take measures to keep them dry when in use.

Plastic dome covers retain heat and humidity. Once seeds have sprouted, remove any soil warming devices and plastic covers. Cooler temperatures and plenty of light will encourage stocky, strong seedlings. Good air circulation helps keep seedlings healthy. I utilize an old box fan to keep the air moving but do not direct the breeze directly at the seed flats.

Treat seedlings with tender care, giving them enough water to keep them from drying out without the soil being constantly wet.

Gradually introduce your seedlings to the harsh outdoors. This process is called “hardening off.”  Place seed flats outdoors in a protected area (away from winds and out of full sunlight) for an hour or two each day, gradually lengthening the time. This is the equivalent of developing a base tan so that your skin doesn’t blister from sudden sun exposure. If a day is especially blustery or unseasonably cool, skip it. There is no place for Tough Love in nurturing seedlings (unless you have sown them too thickly for good air circulation and healthy growth, which is not the topic of this blog).

Check the last frost date in your growth zone, then add a week for insurance before setting your darlings out in the wild world of flower beds, vegetable gardens, or containers. Sometime a stretch of warm temperatures leads us to assume that winter is over. Don’t be misled! It is always better to err on the side of safety than to suffer the loss of time and care invested when Nature has a cold, nasty hiccup.

Why tempt fate? Start only plants that will survive in your zone, soil type, and available light (sun exposure). Plant only vegetables that you and your family will actually eat. It does not matter if you can grow a fantastic bed of eggplant if no one in your family will touch it. Michigan State University has a great chart listing how many row feet to plant per person for various vegetables. Find it by clicking HERE.

Happy Seed Starting! I’d love to see photographs of your successes. Email pictures to mary@marysnoddy.com.

Ready, set, GROW!

These Gomphrena seedlings emerged two days ago, and they are already leaning toward the sun source.

These Zinnia seedlings are growing tall and skinny - a clear sign that they need more light than they are currently receiving.

A moment of silence, please, for this poor seedling that has suffered “damping off” from a fungal attack. The problem was likely caused by too wet a soil, as evident from the sheen of dampness on the starter mix.

The Purple Haze of Lamium

The “purple haze” across lawns and roadsides right now is unrelated to Jimi Hendrix. Instead, it is either Purple Deadnettle or Henbit or both. These weeds are common in the southeast, and can be found growing together. They spread readily and plague homeowners who want a pristine lawn. As a child, I loved the purple flowers with tiny freckles, and gathered many a tiny bouquet as a gift to my tolerant mother.  

A close look reveals the differences between the two. Purple Deadnettle (Lamium purpureum) has heart-shaped leaves, slightly hairy, that attach to the stem with a stalk. The topmost leaves have a purple cast.  Henbit (Lamium amplexicaule) has rounded leaves with scalloped edges that wrap around the stem. Leaves are uniformly green, and attach directly to the stem without a stalk. Stems are square for both, indicating they are members of the mint family. 

These two weeds are not native, but a Eurasian import that has made itself right at home here in the US. While I pull them from my flower beds and borders, I leave those in lawn areas alone.  Deadnettle prefers more sun than Henbit, which prefers shade to partial shade. They appear in all soil types.

Deadnettle and Henbit are reported to be edible. (In this case “edible” means non-toxic and does not equate to “palatable.”) Chickens enjoy eating both flowers and foliage. The blooms provide nectar to honeybees when few other flowers are available, and are also popular with hummingbirds, although peak Henbit season is past when our first hummingbirds appear here in upstate South Carolina. Both plants work well to control erosion (yay!) but set thousands of seeds, all of which seem to germinate (boo!). They can overtake a lawn. 

Both prefer cool temperatures of late winter and early spring, and will gradually fade away once weather is consistently warm. Both plants are annual, so don’t waste time and money applying herbicides.  If you don’t want them in your garden next year, apply anti-emergents in late summer or early fall when dormant seeds are starting to germinate. If you simply must rid yourself of these plants, use an herbicide labeled for broad-leaf weeds and follow the application instructions exactly.

Henbit

Purple Deadnettle

Star Magnolia for Early Spring Flowers

Star Magnolia, Magnolia stellata, is one of the earliest plants to flower each year. It is a slow-growing, short tree (25 feet or less) or large shrub, typically multi-stemmed. The white blooms appear in February or March, and can be damaged by frosts and freezes. Site them carefully, avoiding windy locations and sites with southern exposure that can lead to earlier flowering and worsen cold damage. They can also be grown in a large container. They prefer to be planted in spring rather than autumn.

Star Magnolia tolerates some shade but will flower best when grown in full sun and in moist, neutral to acidic soil. It tolerates heat but not excessively dry or constantly wet soils, and can be grown in zones 4 through 8. Leaves turn yellow in autumn before they drop.

While Magnolia stellata is overlooked in favor of its showier cousins, Magnolia soulangeana and Magnolia grandiflora, its small size makes it easy to incorporate into foundation plantings. It makes a good specimen, especially when backed by evergreen shrubs that will highlight the pure white flowers and the smooth, light gray bark. Several pale pink cultivars are available. 

Star Magnolia is rarely bothered by insects or diseases.

The pure white flowers of Magnolia stellata appear before leaves.

A mature, tree-form Magnolia stellata in flower.

Forsythia Foretells Spring

I spotted a single open flower on my Forsythia this week, a sure sign that spring is almost here. Bring it on!

Forsythia, commonly known as “Yellow Bells,” are old-fashioned, indestructible plants that spread to form large thickets. They are among the earliest of shrubs to bloom. Their arching stems are covered with unscented yellow bell-shaped flowers for several weeks before leaves emerge. Plants bloom on prior year’s wood, so prune thoughtfully. Do not shear into tight meatballs. Instead, use hand pruners to remove entire stems at ground level.

Forsythia (pronounced for-SITH-ee-ah) is hardy in zones 6-8. Its arching stems will reach ten feet in height, with an indefinite spread. It is not choosy about soil type or pH. It is easily transplanted, and rarely bothered by insects or diseases. Deer nibble on young plants but tend to leave larger, mature specimens alone.

In full bloom, this Forsythia hedge looks like a yellow ribbon winding its way through the garden.

Forsythias make a good informal hedge where area is sufficient. Avoid siting them in locations where their aggressive expansion might overtake weaker plants or invade the neighbor’s garden. Plant them in full sun for best flowering. Shrubs reach a height of  feet. Dwarf forms are available, but these also spread vigorously.

Cut a few branches with swollen buds to force blooms indoors.

Flower Timing Dictates Shrub Pruning Schedule

February usually has a few unseasonably warm days, teasers for the spring weather that is still weeks away. Use those days to start on spring gardening chores. I once named Valentine’s Day as the target date for pruning my hybrid tea roses and other summer- flowering shrubs. I no longer struggle with roses (beautiful, but too time-consuming and disease-prone in my hot, humid garden) but mid-February is still a good time to consider pruning.

Broken, damaged or crossing limbs can be removed any time of the year. Prune summer- or fall-flowering shrubs (Gardenia, Beautyberry, Crape Myrtle, Butterfly Bush, Tea Olive) in late winter, before spring growth begins.

For shrubs that bloom in spring (Azalea, Weigela, Forsythia, Lilac, Spirea, Mock Orange), wait until after flowering is over, then prune. Any pruning done in late winter will remove dormant buds and eliminate some or all their flowers.

While it is unlikely that you will kill a shrub by poor pruning, it is possible that the result will be so unattractive that you wish the plant would die. Even if you got a pair of shiny new pruners for Christmas, have a specific result in mind (renewal, size reduction, shaping, thinning, increased flowering) before you start cutting. Refrain from mindless trimming.

Select shrubs whose mature size will fit into your border or foundation bed. When I worked in a garden nursery center, a vein bulged in my forehead every time I heard a shopper announce that they were going to purchase a shrub too large for the intended location and say, “I’ll just cut it back every year to keep it small. It will look okay.” Please, I implore you, do not be that person. Because you won’t. In five years, the shrub will either have outgrown its space or its natural shape will be lost by excessive pruning. Butchered plants look horrible.

To obtain privacy from a dense hedge, start pruning when plants are small. Use hand pruners to cut back the tips of each branch. This will make dormant buds along the stems wake up and produce new branches. Repeat this tip removal as needed to encourage additional branching until the hedge is approaching the desired mature size. Informal, loose hedges are easier to maintain than tight shapes, but a sharply-edged hedge gives a lovely, formal appearance. You can use powered (electric, gas, battery) hedge trimmers to trim hollies, boxwoods, Ligustrum and similar shrubs into tight shapes, but always cut at a slight angle so that the top is narrower than the bottom. When done properly, this allows sunlight to reach the lower leaves as well as the upper ones and prevents leaf-loss near the ground. The angle does not need to be exaggerated to be effective – think of the bottom half of the letter A.

Think twice before planning a formal, tightly pruned hedge of Azalea, Forsythia, or Loropetalum. These plants look best when allowed to maintain their open, spreading shapes. Restricting them into a narrow strip will require frequent trimming and result in reduced flowering.

Conifers respond poorly to hard pruning. Yew, juniper, and Arborvitae rarely break new growth from old stems. Light tip pruning is okay. Remove dead or damaged branches; otherwise, leave them alone. For broadleaf shrubs like Aucuba, avoid cutting large leaves. Instead, reach loppers to the interior of the shrub to make cuts, removing entire branches. This will increase airflow and allow sunlight to enter the interior. Boxwoods, a staple of many southern gardens, look their best and are healthier when pruned this way.

Hydrangeas require special attention to pruning. Those that bloom on new growth (‘Incrediball’ or ‘Limelight,’ for instance) should be pruned in winter. Those than bloom on old growth (oakleafs, many of the old-fashioned mopheads) should be pruned immediately after flowering. Some, known as rebloomers (‘Endless Summer’™ types), bloom on both new and old growth. If you plan to add a new Hydrangea to your garden, purchasing a rebloomer will ensure that you still have some flowers if a late freeze zaps buds that have already started to open. What if you don’t know which cultivar of Hydrangea you have? Leave them unpruned one season and pay attention to where the flowers occur. Use this information as your guide for future years.

When using hand pruners or loppers, prune just above a bud. In this case, “above” means between the bud and the tip of the stem (not between the bud and the end of the stem that meets the ground.) Don’t leave too much stem between the bud and the cut, or the stub will die. Don’t cut too close to avoid damaging the bud itself. Make an angled cut near the bud (between the bud or stem). New growth will angle off the pruned branch in the same direction as the bud. See the photos for an illustration.

Too far from bud leaves stub

Too close damages bud

Just right!

Happy Winter Faces of Pansies, Violas

Pansies are a popular flower choice for winter color. Pansy (Viola x wittrockiana) is a biennial used as a cool-season annual. In the Southeast, plant them in fall and enjoy their flowers until late spring, when heat causes their demise. Pansies are available with solid blooms, but many have multicolored blotches that look like happy faces. Colors are so consistent that they can be planted in swaths to create a pattern or tapestry effect.

Plant pansies in full sun to part sun, in well-drained soil, zones 6 through 10. They are not picky as to soil pH (acid, neutral, or alkaline) or type (clay, sand, or loam). They prefer a moist soil, so add a little irrigation if winter rains are lacking. Pansies will flower continuously in fall and cool spring, taking a little break in the worst of the winter. In the mild winters of recent years, they have flowered from September through May in the Mary Snoddy garden.

Remove spent flowers regularly to encourage more blooming. I find a pair of cheap dollar-store scissors ideal for this task, allowing me to easily remove the spent flower and its entire stem. It looks a bit creepy to remove the petals and allow the decapitated stems to remain.

Pansies are available in both upright and spreading forms. The upright types do not exceed 12” in height. The trailing forms make a beautiful hanging basket, which has the advantage of allowing the container to be moved to a protected area in the most frigid of temperatures, then returned to a sunny spot once those teens and sub-teen temperatures have abated.

The old-fashioned common name, “Hearts-ease,” refers to the yellow and purple, small-flowered ancestor from which today’s large, showy blooms arose. A closely related plant, Viola tricolor, is commonly called “Johnny Jump-Up” or “Wild Pansy” or simply “Viola.” These are smaller in stature and bloom size, but they make up for their small size by exuberant flowering. They are available in solids or bi-colors, although not as many variations as the large-faced pansy. They also reseed readily, and if left undisturbed will create colonies in deciduous woodlands.

Both pansies and violas are edible. They make pretty decorations for sweet goods, but are not flavor powerhouses. If you choose to “candy” the flowers for food decoration, it is best to use a pasteurized egg-white product (find this in the refrigerated section at your grocery) rather than straight-from-the-shell egg white to eliminate any chance of foodborne salmonella.

The yellow and purple flower of this Pansy makes me think of buttered toast with grape jam.

Violas (“Johnny Jump Ups” have reseeded to cerate a mat of flowers.

Evergreen Shrubs for Shade

Evergreen shrubs give life to the winter garden. In warm weather, they provide a background that makes other plants, especially flowers and variegated specimens, look better by contrast. Last week we looked at several good choices for sun. Today, let’s a look at a couple of good background evergreens for shadier areas.

While most Viburnum (pronounced vih-BUR-num) are deciduous, evergreen Viburnum awabuki ‘Chindo’ has large, glossy leaves that are equally attractive as a backdrop or a featured specimen. ‘Chindo’ grows fast – one to two feet per year – and will thrive in almost any soil. It won’t do well in deep shade, but dappled shade or partial shade prevents leaf scorch. Mature specimens will have clusters of small white flowers and clusters of red berries that look fabulous against its deep green leaves. ‘Chindo’ naturally forms a pyramidal shape. It will be loose in part shade, dense with more sun. It will grow in zones 7 through 9, and is drought tolerant once established. Allow plenty of space, because a mature plant will reach 12 feet tall and 8 feet wide. Deer tend to avoid the thick leaves of this easy shrub.

Glossy Chindo leaves

Juvenile Chindo in shade

Camellia sasanqua and Camellia japonica (pronounced kah-MEE-lee-ah jah-PON-ih-kah) are well known and beloved for their shade tolerance and their beautiful blooms. Camellia japonica prefers partial to full shade. It is a good choice for woodland gardens. C. japonica leaves are larger than C. sasanqua, probably to increase photosynthesis in lower light levels. There are numerous cultivars. These tall shrubs are slow growing but will reach 12 feet or more.

Camellia japonica ‘Professor Sargent’ is popular and widely available.

Camellias grow in zone 7 through 9, in well-drained acidic (pH 5.5 to 6.5) soil containing plentiful organic matter. They produce showy flowers in winter, in shades of red, rose, white, pink, and bi-colors. Flower forms range from singles with prominent yellow stamens to “formal double” types with overlapping petals and no visible stamens.

Very cold temperature or ice and snow may damage Camellia flowers, causing them to brown and drop off. Buds are numerous, so flowering will resume when weather extremes abate. It is best to rake up and discard fallen flowers, to help prevent diseases and insect problems. Yellow leaves are a symptom of too alkaline soil. Purchase plants that are actively blooming to ensure your selection is your preferred color. My favorite cultivar is ‘Nuccio’s Pearl,’ a formal double white flower with a slight pink flush. Gorgeous! Until blooms get zapped by cold, that is. Then they turn a sickly tan and fall off a few days later.

The Cephalotaxus genus (“Yew” or “Plum Yew”) offers species that fit any growth habit desired - spreading, upright, skinny. The fernlike, needled foliage emerges light green and matures to a deep, rich green. All forms are slow growing and happy in shade. I decided to take a chance and planted Cephalotaxus harringtonia ‘Fastigiata’ in a sunny area next to my home. I have given it supplemental irrigation during drought. Despite being recommended for shade, it happily matured to 15 feet tall, four feet wide. It is a good source of holiday greenery, since cut stems last a long time in water and provide good contrast to the more traditional Christmas greens. Its narrow mature width makes it a good alternative to ‘Sky Pencil’ holly.

Mature upright Yew

Soft needled foliage

New growth is bright green

My favorite evergreen shrub for shade is Osmanthus (pronounced oz-MAN-thus), or Tea Olive. Shrubs flower in late summer to autumn, a clean, fruity fragrance that every nose enjoys. The white flowers are tiny but numerous. An orange-flowered variety is available but it blooms less profusely than the white.

Osmanthus fragrans will reach heights of 20 feet, in zones 8b through 11. Its leaf edges are smooth or very slightly toothed. Osmanthus x fortunei, Fortune’s Tea Olive, tolerates more sun and more cold than O. fragrans. It will reach heights of 25 feet, in zones 7b through 10. Juvenile leaves are toothed while mature leaves tend to have smooth margins. The cultivar ‘Fruitlandii’ has outstanding fragrance.

Osmanthus heterophyllus has leaves that strongly resemble Holly (Ilex). It is sometimes called “Holly Tea Olive.” It matures at 15 feet, which makes it easier to incorporate into a mixed border. It will tolerate a more alkaline soil than the first two. A variegated form, ‘Goshiki,’ is a favorite in the Mary Snoddy garden. ‘Goshiki’ means “five colors,” an allusion to the dark green, light green, cream, and white leaves. New growth is a rosy pink. I find that ‘Goshiki’ blooms less than the others, but it may be because I keep it sheared into tight cones. You may have noticed that I have an affinity for gumdrop-shaped topiary. Deer usually ignore all members of the Osmanthus family, especially after they gain size.

Small flowers, big fragrance

Topiary Osmanthus 'Goshiki'

I cannot leave the subject of evergreen backgrounds without a mention of narrow choices. If your home is site on a narrow lot with neighbors close on either side, the space between houses is shaded by the structures themselves. When seeking “skinny” shrubs, look for “fastigiate” or “columnar” on plant tags. Both these mean the shrub has a narrow profile. If space is super tight, consider growing vine Confederate Jasmine or Clematis armandii on a fence to provide privacy and a solid green backdrop.

Evergreen Shrubs for Sun

Evergreen shrubs make companion plants look better by comparison. Our appreciation increases in mid-winter, as they liven up gardens and give color to borders that are otherwise collections of lifeless, leafless sticks.

My favorite evergreens for sun and partial sun are Buxus (Boxwood),  Juniperus (Juniper), Ilex (Holly), Cryptomeria, and Thuja (Arborvitae).

This row of Buxus microphylla ‘Morris Dwarf’ makes a good border at the top of a rock wall. Purchased as 4-inch bareroot “liners,” they are ten years old, and only 12 inches tall.

Boxwoods are a garden staple in the south. Gardeners can find a Buxus to fit their site and zone. Dwarf forms look great in containers, too. Boxwoods are slow growers, so they do not require frequent pruning when grown directly in the ground or repotting when grown in containers. Their foliage has a pungent odor that some people find offensive. I find that the tiny cultivars are more expensive that their large cousins.  

Junipers have needle-like foliage and withstand heat well. Cut branches have a resinous fragrance that enhances seasonal Christmas arrangement. Once branches dry out, though, those needles become sharp and shed readily.

Hollies (members of the Ilex family) are thick-leaved shrubs with cultivars that range from giant to dwarf. Please note: a dwarf ‘Burfordii’  holly will still grow to 12 feet or more. Holly flowers are tiny but loved by honeybees. Burford hollies are favored for their heavy berry-set. Most hollies have red berries but a few have yellow or orange berries. If you have space for a specimen that will reach  20 feet in height with a 15-foot spread, Ilex ‘Liberty’ is a fast grower (to 18 inches per year) with a beautiful pyramidal shape. It is a dense shrub when grown in full sun but more open when grown in part shade.

Most Cryptomeria cultivars are large, elegant trees but Cryptomeria globosa ‘Nana’ is a shrub. Globosa means “round” and Nana means short. These terms are relative, however, and in the Mary Snoddy garden C. globosa ‘Nana’ has grown to 5 feet. It has a unique texture that makes visitors touch it. 

The most popular Thuja cultivars are ‘Green Giant’ Arborvitae and ‘Emerald Green’ Arborvitae. The first reaches 60 feet with a 20 foot spread. The second reaches only 15 feet in height, making it easy to incorporate into smaller home gardens.

Each of these shrubs have cultivars that vary in mature size and cold hardiness. Check plant tags to ensure that you purchase specimens that are appropriate for your site.

Next week, I’ll share my favorite evergreen shrubs for shade, as well as some recommendations for narrow plants that can be used for privacy hedges in small gardens.

This lovely Cryptomeria globosa ‘Nana’ looks fabulous against a red barn, especially in contrast to the silber foliage of Artemesia ‘Powis Castle.’

These Ilex compacta hollies were planted 12 years ago from one-gallon containers. They are now five feet tall with an equal spread. While the natural shape is round and somewhat irregular, these have been pruned into gumdrop topiaries, leading the eye to the front entrance. They need maintenance pruning every six weeks to maintain this tight shape.

Is Snow Good for the Garden?

Much of the southeast received snow over the past weekend, setting new records in places like Asheville, NC and Greenville-Spartanburg Airport, SC. We make bad jokes about Mother Nature’s multiple personality disorder, but in the Deep South you will find snowboards next to flip-flops and sunscreen in our mudrooms. Shorts one day, down vests the next. Our snowstorms are rare and never last long, so we treat them as a special holiday. Is snow a good thing for our gardens? Yes and no.

Snow Pros: Insulation. irrigation, fertilization.
It is difficult to consider a cold, wet blanket as insulation, but snow protects plants from drying winds and frigid temperatures. Its fluffy texture acts like a goosedown blanket, holding any ground warmth at soil level. This insulation can protect roots and leaves from freezing, and will allow underground bacteria, fungi, earthworms and such to go about their business, albeit a little slower than normal. Snow will maintain an even temperature around plants that is far preferable to alternating warm/cold cycles that damage plant tissues.

Melted snow provides water to plants at a slow rate. Think of it as a drip hose that covers your entire garden.

The concept of snow as fertilization seems odd. Older almanacs referred to snow as “Poor Man’s Fertilizer.” Snow captures minute amounts of nitrogen and sulphur from the air and delivers it to your soil. This does not negate the need for fertilization (as indicated by a soil test, of course), but it certainly does not hurt, especially on marginal soils.

Snow Cons: Weight, bark split, container exposure
The weight of snow can damage evergreen trees and shrubs. The broad leaves of Magnolia grandiflora hold snow, and the needled foliage of Cedars. Arborvitae and Junipers hang onto ice. Dry, powdery snow can be swept off shrubs with a broom. I have also used a leaf blower, but it was less effective than I imagined. Brittle shrubs like Rhododendrons can be wrapped with rope to hold them upright, making a smaller target for snowfall to create damaging weight.

The bark of young trees may be damaged by gnawing animals or split from rapid temperature changes. Garden centers sell trunk wrap to help with the latter. Pull snow away from tree trunks to prevent the former.

Container plants are more likely to suffer from cold damage since snow insulates the top but leaves the sides exposed to cold. Move these into a protected area if you can. If not, a layer of clear bubble wrap helps.

Two closing thoughts:

Utilize plants that are cold-hardy in your garden’s zone. It is unreasonable to expect a tropical plant to survive in zone 6 winters, no matter the amount of snow insulation it receives.

 A final benefit of snow: It conceals all those garden chores you did not accomplish. Those spent annuals and dead vines are merely lumps under a gorgeous white icing. Enjoy!

Our driveway is unrecognizable under its snow blanket.

Flowering Quince

Chaenomeles (pronounced ky-NO-may-leez) is a deciduous shrub that is commonly known as Flowering Quince, Apple Japonica or Japonica Pear. Its flowers open in earliest spring, before leaves appear. Flowers mature into fragrant, yellow, rock-hard fruits that are slightly larger than golf balls. These are inedible off the plant, but can be processed into jelly. Cut stems of Flowering Quince can be forced into bloom indoors. Prune judiciously to improve shape and encourage branching. 

Two species, C. japonica and C. speciosa, are common in the southeast, as well as a hybrid of the two, C. x superba. They are similar, but speciosa has a more upright shape, dense twiggy interior growth, and sharp thorns. C. speciosa grows to six feet tall. C. japonica is shorter, reaching four feet. Chaenomeles requires acidic soil and full sun for best flowering, but will accept some shade. It grows in zones 5-9 and prefers average, slightly moist to dry soil.

Flowers are red, orange, pink, white,  or burgundy. Blooms are normally five-petal singles, but the ‘Double Take’ series are doubles. ‘Toyo-Nishiki’ has pink and white flowers on the same plant. ‘Cameo’ has a lovely semi-double, peach flower.

Chaenomeles are easily grown and are deer resistant. They occasionally host aphids and several varieties of leaf spot.

The rosy flowers of Chaenomeles are a bright spot in the gray days of winter.
Image by Couleur from Pixabay

Bell-Like Brugmansia, Angel's Trumpet

Brugmansia is sometime confused with lookalike Datura, to which it is related. They share a common name (“Angel Trumpet”) and flower shape. The bloom orientation easily distinguishes the two. Brugmansia flowers dangle like bells, while Datura blooms are upright. Brugmansia seed pods are smooth while Datura’s are prickly, like a chestnut. Brugmansia has a woody stem; Datura is herbaceous, dying to the ground each winter.

Brugmansia is a bold plant, meant for the back of the border, as a specimen, or standing alone in a foundation planting. It is considered a tropical shrub or small tree, with mature height from 6 feet to 15 feet. It is cold hardy in zones 7b through 10,  but can be grown as a houseplant or in a warm, protected microclimate (next to a brick home, for instance) in cooler locations. Use a thick winter mulch of leaves or pine needles to keep Brugmansia cozy in winter.

Brugmansia (pronounced brug-MAN-zee-ah) flowers come in beautiful shades of yellow, apricot, pink, or white. The petals of the funnel-shaped blooms can be as much as a foot long. A mature plant in full flower is impressive. Brugmansia does not start to flower until it reaches a degree of maturity. Purchase a rooted cutting rather than starting them from seeds to achieve flowers earlier. Strangely, cuttings taken from the same plant can vary in flower color when grown in different soils and sun exposures. Flowering lasts for weeks, often all the way to frost.

While the flowers are beautiful and sweetly fragrant, especially in evening, avoid inhaling too long. Lengthy exposure can cause headaches and even nausea. Crushed foliage smells bad. 

Brugmansia is not a plant for shade. It prefers partial sun to look best. The eastern side of a house, with morning sun and afternoon shade, is an ideal location. If a mature plant starts to look wilted or leaves turn pale green, the diagnosis is usually too much sun. It is not demanding as to soil type, and is moderately drought tolerant once established. Brugmansias are hungry and thirsty. Flowering will be more profuse with regular fertilization and irrigation, although boggy soils induce root rot.

The leaves and flowers of Brugmansia are toxic if ingested. Deer normally don’t nibble plants or flowers.

Brugmansia flower

The adjacent brick wall provides warmth for this Brugmansia, extending its flowering season by several weels.

My Neighbors Say "Happy Moo Year"

I’m taking a writing vacation this week. Instead of horticulture information, I’m sharing photos of my neighbors, a fine group of Charolais cattle. May your 2022 be healthy and happy!

Why Plant Names Change

Why do plant names change? Name alterations present a challenge for growers (updating plant tags, catalogs, signage), teachers (memorizing and educating with current names), and gardeners (finding the desired plant). So why not let well enough alone? As it turns out, there are good reasons for changes.

First, a quick taxonomy note. We owe the Genus/species/‘Cultivar’ binomial naming scheme to 18th century Swedish naturalist Carolus Linnaeus. Latin Genus is always capitalized and italicized. It is followed by lower case species, also Latin and also italicized. The species is descriptive. For instance, ‘globosa’ means globe-shaped or ‘japonica’ means Japanese. Any specific cultivar is capitalized and surrounded by single quotes. Example: Cercis canadensis ‘Forest Pansy.’ These names are identical across all countries, all native languages. A species name is never used without its genus.

A change in plant name may occur to correct a mistake. If two different botanists named the same plant, for instance, the earliest name will be adopted as the correct one. And a plant cannot have two different genus/species labels – chaos in the garden!

Just as human DNA testing has increased in sophistication, plant genome mapping has caused the reclassification of some plants. One such reclassification is Coleus. We all know a Coleus when we see one, right? In 2006, Coleus had a name change to Solenostemon. In 2012, it was renamed to Plectranthus. And in 2019, it was renamed, again, to Coleus. Whew!

One of my favorites, Sedum spectabile ‘Autumn Joy’ is now Hylotelephium telephium 'Herbstfreude' which looks very much like the naming botanist’s cat walked across the keyboard. 

The reclassification that still has me scratching my head is our southern icon, the native Dogwood, Cornus florida. Since 2014, it has officially become Benthamidia florida, although I see no evidence of changes in our local plant centers. Old habits die hard. I’ll just call them Dogwoods.

Finally, we can call this plant Coleus again.

Dawn Redwoods with Pumpkin-Spice Colors

The downside of relocating to a new home is the loss of favorite plants in the former garden. Sometimes these are valued for their rarity. In other cases, they serve as reminders of friendships or life milestones.

For me, leaving behind a Dawn Redwood tree was a source of sadness. I received it as a rooted cutting in 2006, at a Master Gardener plant swap. At less than a foot tall and living in a four-inch nursery pot, it was hardly imposing. Luckily, I checked my favorite reference manual (Manual of Woody Landscape Plants, by Michael A. Dirr) and learned that this scrawny specimen that resembled a green feather could reach a mature height of 100 feet with a spread of up to 40 feet.

Dawn Redwood (Metasequoia glyptostroboides, pronounced met-uh-see-KWOY-uh glip-toe-stroh-BOY-deez) is one of the few deciduous conifers. It grows fast (up to two feet per year), with a lovely pyramidal shape when young, maturing to a rounded crown. Given average growing conditions, a tree will reach 25 feet or more in ten years. They make a wonderful specimen. The tree in the zone 7 Mary Snoddy garden, now 15 years old, exceeds 30 feet. It has received no supplemental irrigation after the first year.

These trees enjoy moist, acidic soil, and will not tolerate dry locations. Mature trees have a furrowed look to the bark. They are hardy in zones 5 – 8. With age, the lower limbs droop downward with age, giving the tree a graceful look. Lower limbs may need to be removed if they block views or prevent mowing. The foliage turns a gorgeous, rusty orange before shedding in the fall.

It is easy to confuse Dawn Redwood with Bald Cypress (Taxodium distichum). Look at the leaf arrangement to distinguish the two. The half-inch needle-like leaves of Dawn Redwood are held on the stem in an opposite arrangement, while the Bald Cypress leaves spiral around the stem. Both trees will do well in soils with limited oxygen. Dawn Redwood tolerates clay soil. In swampy soil, the Bald Cypress will push up “knees” to capture air that is not available to its roots.

Dawn Redwood has no disease problems, although Japanese Beetles occasionally eat the foliage. Deer rarely browse them.

Metasequoias are propagated from cuttings or air-layering. Young Dawn Redwoods transplant easily. They can also be grown as bonsai.

This Dawn Redwood (Metasequoia) is 15 years old and stands more than 30 feet tall.

Same tree as above, showing its summer foliage color.

In spring, the needle-like leaves of Dawn Redwood are a bright green. They darken to a medium green in summer.
This photo by Zhu Bing from Pixabay