Mandevilla, Dipladenia, Allamanda

I received a Mandevilla vine as a Mother’s Day gift this year. A wooden trellis was included. It dwarfed the plant. Fast forward two months, and this woody vine is a knockout! Healthy, dark green leaves set off the blood-red, tubular flowers to perfection. The vine has grown enough to cover the trellis without becoming aggressive.

Mandevilla (pronounced man-de-VILL-uh) has large, tubular blooms that attract hummingbirds. Mine is red but I have also seen pink, rose, yellow, and white in nurseries. The vine does not have suckers, but will twine gently around a supporting trellis. They make an ideal mailbox-post accent or hanging basket. Dipladenia (rhymes with Gardenia) is an upright, bushier form of Mandevilla that is now included into the Mandevilla genus. To confuse matters further, some were formerly labeled as Allamanda. The upright forms have smaller, more pointed leaves than the original, viney Mandevillas. All types enjoy rich, moist soil that drains rapidly. A mixture of potting soil, sand, and ground bark works well. Spent blooms fall off without any help from the gardener. Pinch the tips of vines to make plants fuller. In the southeast, Mandevillas will appreciate afternoon shade and frequent irrigation.

Mandevillas are warm weather plants, winter-hardy only in zones 10 and 11. This is why many of them are grown in containers, to facilitate bringing them indoors for winter. Container culture also restricts the mature size. Grown directly in the ground, a vine may reach 15-20 feet. In a container, it will rarely exceed 6 feet. When night temperatures drop to 50 degrees, Mandevilla can be brought indoors to a bright location (no direct sun) and enjoyed as a houseplant, although flowers are fewer than in summer. Water indoor plants sparingly, allowing soil to dry out while giving them a winter rest. Keep an eye out for aphids, whiteflies, mealy-bugs, and scale. Remove any dead or damaged leaves. Prune hard and apply liquid fertilizer when they return to an outdoor location in spring.

Mandevilla ‘Red Riding Hood’

Stars and Stripes in the Garden

In honor of Independence Day, today’s blog will focus on Stars and Stripes. Pentas lanceolata ‘Stars and Stripes’™ is cold-hardy down to 20 degrees, so it is perennial only in zones 9b and warmer. I grow it as a annual in zone 7b.

Solid green leaf Pentas are available in red, pink, lavender, rose, purple, and white. The common name, Egyptian Star Flower, is a good description of the clusters of tubular nectar-rich blooms that attract hummingbirds, bees, and numerous butterflies. ‘Stars and Stripes’ has bright red blooms, and the green and white variegated foliage is outstanding.

I first saw Stars and Stripes in a local botanical garden, where the horticulturalist paired it with ‘Hot Lips’ Salvia. The combination of red and white Salvia blooms paired with the variegated foliage and red blooms of the Pentas was a clear winner. It impressed me enough to repeat the combination in my own garden, although now I allow the Pentas to take center stage without competition from the bushy Salvia.

Pentas lanceolata (pronounced PEN-tass lan-see-oh-LAY-tuh) are heat lovers that do well in either flower beds or containers. They look super when planted in masses. They are relatively drought tolerant, but those in containers may need irrigation in the hottest, driest months. They prefer a pH neutral soil. Plants bloom throughout the summer, even more prolifically when dead-headed.  They are compact growers, reaching up to 24 inches with an equal spread. Should they ever get unwieldy, they can be pruned and will bunch obligingly.  Pentas prefer full sun but will survive in part-sun, although the stems may flop a bit. The ‘Graffiti’ and ‘Lucky Stars’ series are both shorter, reaching 16 inches or less.

The only weakness I have found is that the stems are somewhat brittle, so you should plant them in an area where they won’t be damaged by high winds or when the family dog exhibits an enthusiastic case of the “zoomies.” (Dog owners know what I mean. For the uninitiated, some dogs tend to run in circles, full-speed with wild abandon, for no apparent reason, leaving a wake of plant destruction.)

As an added bonus, deer ignore Pentas.

Stars and Stripes, blooming in time for July 4 celebrations.

One of the non-variegated types.
The Lucky Stars penta series has a compact growth habit and vibrant colors as seen in this Lucky Star lavender. (Photo by MSU Extension/Gary Bachman)

A mass planting of pentas. Photo used with the kind permission of The Neighborhood Nursery, 131 Woods Road, Fountain Inn, SC. Please support your local nurseries! @TheNeighborhoodFarmSC

Lucky Buckeye

Another Christmas season is in the books. When I was a young child, I was enthralled by the concept of “chestnuts roasting on an open fire.” I nagged my long-suffering mother into purchasing a bag of these nuts and cooking them in our fireplace. That statement is remarkable for two reasons. First, we didn’t have chestnut trees on any family property, so she had no experience with the nuts. Mom was never eager to try anything new. Second, I can count on one hand (truthfully, two fingers) the number of fires kindled in our family fireplace during my childhood. Our house was built in the 1940’s and the tiny firebox was designed for coal-burning, not wood. As a consequence, a log fire billowed smoke into the house interior, stainining walls and incurring the wrath of the matriarch/housekeeper.

Smoke fiasco aside, our carol-induced experiment took a bad turn when the nuts heated up. We did not know that we should have cut a slit in the hulls to allow for the escape of steam. Mom learned that an exploding chestnut makes a sound not unlike a pistol shot. The detonated nuts flew across the room, leaving trails of scalding hot innards. She attempted to remove the remaining nuts from the fire’s edge before they blew, with limited success. I learned a few new words that day. Even as a six year-old, I knew better than to laugh at a frazzled mother dotted with sizzling nut guts. Oddly enough, she was mad at crooner Nat King Cole and not me.

Decades have passed. I have learned that, despite the similarity in seed appearance, the chestnut and the buckeye are markedly different. Chestnuts are edible. Buckeyes are not.  Ingesting a buckeye can cause kidney failure. Chestnuts are encased in prickly husks that remind one of Oscar The Grouch. Buckeyes are encased in spineless, lobed seed pods that look a little like a misshapen fuzzy brown kiwi.

The subject of today’s blog is the Red Buckeye, Aesculus pavia, pronounced ESS-kew-lus PAH-ve-ah. This deciduous tree is native to the southeastern US. Its short stature (10 to 20 feet) and clump-forming habit leads the gardener to treat it as a large shrub. It is one of the first trees to leaf out in the spring and one of the first to shed leaves in the fall. Beautiful red bloom panicles up to six inches long are borne at the ends of the branches in early spring. The nectar-rich flowers are irresistible to hummingbirds and butterflies, and are ranked among the top ten hummingbird plants for South Carolina.

Trees prefer moist but well-drained soil. They function best in an understory role with dappled shade, since the tender leaves scorch in full sun. The crown will open up a bit in denser shade. They do not tolerate severe drought, but will die in a waterlogged soil.

The seed pods open to release mature nuts in September to October. It is possible to start Red Buckeye from seed, but you’ll need to work fast to beat the squirrels. The seeds degrade quickly once shed, so should be planted as soon as they are gathered. Seeds require three months of cold, moist stratification to germinate. This can be accomplished by refrigerating seeds in a bag of damp sphagnum moss before planting them in the ground or in a nursery container. The easier method is to place seeds in a porous potting mix outdoors through the winter, allowing Mother Nature to do the chilling and watering. If you take the latter route, use protection (wire mesh) to prevent squirrels from unearthing the nuts. The potting mix must be free-draining or seeds will rot. Seedlings grow quickly and can flower in two to three years.

Carrying a buckeye in the pocket is supposed to bring good luck. Just don’t eat it.

Photo courtesy of Josh Williams, from the Clemson Extension Home Garden Information Center. See Bulletin 1031 for information and photos of Red Buckeye and all its relatives.

https://hgic.clemson.edu/factsheet/buckeyes-horsechestnuts/

Red buckeye, ready to drop from its seed capsule.