In the Heat of Summer

How does your garden grow?

These stately crape myrtles thrive in Columbia’s heat and humidity. As the trees mature, the bark becomes mottled, which adds even more interest to the garden.

photography by Emily Clay

The heat of July and August wilts more than just nicely starched cotton blouses and perfectly coifed hairstyles. It also wilts nearly everything in the garden. The spiked summer temperatures certainly create a challenge for gardeners in the Midlands. It might be that your trees and shrubs are thriving and adding beauty to your personal oasis, or they might be drooping and hanging on to life by a thread. As you cast your glance around your yard, are the perennials and annuals full of showy flowers, or are the blooms crunchy from the intense heat or soggy from the high humidity?

If your garden looks rather discouraging right now, there is hope. Many wonderful and beautiful trees, shrubs, perennials and annuals thrive in Columbia’s famously hot climate and provide interest and color in the garden all summer long. Gardeners may not relish hours and hours in the garden during these hot and humid months, but it is a good time to evaluate the success of plants and make plans to remedy any problems in the coming fall or spring. Pull out a pad of paper, head outside in the cool of day and make note of the areas that bother you and consider replanting with suggestions from the following list.

Ornamental Trees
Let’s start with some of the largest and most important members of the garden: ornamental trees. Trees add character to the landscape, and they provide much needed shade and nesting places for many birds. Ornamentally, they add height and vertical interest to the garden. Fortunately, many beautiful and majestic trees thrive in Columbia’s hot summers. This list focuses on smaller, lower canopy trees.

Crape Myrtles (Lagerstroemia indica): These deciduous Southern landscape beauties add year round interest to the garden with their sculptural form, exfoliating bark, beautiful color and long lasting blooms. Crape myrtles are fast growers and can reach 20 to 40 feet. They prefer full sun and have handsome peeling bark. “Natchez” is an attractive, low maintenance, white variety that is resistant to mildew and is wonderful planted near a patio to provide shade and color. It also works well to define a path or driveway. To see a wonderful example of mature crape myrtles, visit the gardens at The Lace House on the Governor’s Mansion complex. There is a charming allé of crape myrtles, and these particular trees display the beauty of their old growth trunks.

Chaste Tree (Vitex agnus-castus): Long lasting lavender flowers cover these manageable sized trees beginning in late May and last through the summer. Vitex are usually multi-trunked and respond well to pruning. They are fast growers, soil tolerant and thrive with moderate to little rainfall. After the flowers mature, small seeds cling to the branches until the next year’s growth pushes them off. These seeds are favorites for many of South Carolina’s birds. Cardinals particularly love them during the colder months, so it is a good specimen to plant near a bird feeder or in a bird viewing area. Vitex also do well when included in a perennial border to add height and long lasting summer blooms. An attractive row of these trees is planted on Senate Street near Trinity Cathedral. They are usually in full bloom in mid to late May.

Fig Tree (Ficus carica): There is no finer Southern specimen than a fig tree. These deciduous perennial favorites are very adaptable to less than ideal conditions. They thrive in full sun, and the fruit is actually much sweeter during years with little rain. The candelabra shape is beautiful in the winter garden, and the emerging leaves in the spring are enchanting. Fig trees are wonderful to use to anchor a vegetable or kitchen garden or to plant on their own in an orchard. The mature leaves are interesting as table decorations or to line a platter of cheese or fruit. Of course, wash them thoroughly before they are used for decoration. The “Brown Turkey” variety produces a bounty of fruit that is delicious to eat right off the limb. There are exotic recipes for figs with goat cheese and herbs. And, there is nothing more Southern than fig preserves.

Evergreen Foundation Plants
The next category to explore for the summer garden is shrubs. There are many heat tolerant shrubs of varying sizes, so this list will include a small, medium and large example.

Dwarf Pittosporum (Pittosporum tobira): No Southern garden is complete without pittosporum. These charming, small evergreen shrubs have shiny dark leaves, form a dense mound and have small white fragrant blooms in the spring. This spring was a particularly good year for pittosporum flowers, which add a delicate element to cut flower arrangements. The variegated form does not do as well as the all-green form. A staggered row of dwarf pittosporum contributes structure to a traditional foundation planting. They average in size from three to four feet tall to three to four feet wide and can be pruned to maintain a certain size.

Fatsia japonica: Once established, this medium sized, tropical looking shade lover can tolerate the intense heat of July and August. Fatsia has dark green, palmated leaves that add an exotic flair to a foundation planting. Fatsia can be included in container plantings as well. Coupled with other plants that prefer low light, such as autumn fern, aspidistra and ivy, fatsia adds appealing vertical interest to the grouping. Flower arrangers appreciate the tropical look of the leaves to add to a cut flower arrangement.

Cleyera japonica: Just like its shade-loving companion, cleyera japonica is a favorite in the Southern garden. After proper planting and irrigation, this pest-free large shrub thrives during the summer months. Cleyera adds a vertical element to the garden and is well used as a foundation plant or as a screen or hedge. It can be pruned into a tree or standard form or shaped into a squared off hedge or left in its natural form. This medium textured shrub is a very versatile choice for the garden.

Herbaceous Perennials
Perennials are the fun and bright part of the summer garden. They are blooming, herbaceous plants whose top growth usually dies back to the ground in the winter. One of the most desirable attributes of perennials is that they do not have to be replanted every year. Some do benefit from division every three to four years so that there are more to plant in different areas of the perennial border. There are literally hundreds of perennials that are perfectly suited to this warm climate, Zone 8. The following perennials grow in the gardens at The Riverbanks Zoo and Botanical Garden, so a visit there during summer will demonstrate how they thrive. Following is a list of three tried and true perennials to consider for a Columbia garden.

Black Eyed Susan (Rudbeckia): If there were room for only one perennial in the flower garden, this is the best choice. Rudbeckias, which can grow to two to three feet, thrive and proliferate in well-drained soil. With consistent dead-heading, they will continue to bloom. The bright yellow blooms with a brown or black center usually appear in early to mid June and will last until Thanksgiving. The blooms are long-lived and are long lasting as cut flowers. This is a true workhorse in the garden.

Bee Balm (Monarda didyma): Bee Balm is another tireless performer in the summer garden. Monarda is a member of the mint family and is a vigorous grower and bloomer. It is very content growing near a dripping faucet or sprinkler head. Just as its name suggests, it is a favorite of bees. The prolific white, pink, lavender or red blooms are catnip to hummingbirds and butterflies, so it is a wonderful and beneficial addition to the perennial border.

Lantana (Lantana canara): Lantana are tough, low maintenance perennials that add continuous color to the summer flower garden. Lantana grows from two to four feet and can spread as wide or even wider. The color spectrum of the blooms is vast and varies from yellow, pink, red, white, purple and orange. Many varieties are multi-colored. Other varieties have variegated foliage that adds color and texture to the garden and container plantings. These drought tolerant, old-fashioned bloomers also attract hummingbirds and butterflies.

Bedding Plants
Annuals are plants that complete their entire life cycle from seed to flowering during one growing season. They provide the most consistent and long lasting color in the summer garden. Some annuals sold in local garden centers are better suited to the Midlands’ spring temperatures and do not perform as well during the hot summer months. This list includes examples that should survive the hot temperatures of July and August when planted in properly prepared soil, watered regularly and fertilized monthly.

Begonia, Wax Begonia (Begonia semperflorens): Begonias are such versatile and rewarding annuals to include in the summer garden. There are varieties that thrive in sun or shade. They can be used as bedding plants, in hanging baskets and in containers. They root very easily, providing plants for the next year. Their blooms vary from white to light pink to pink to red. Many begonias have dark leaves that add even more interest to the display. Dragon wing begonias, which come in pink and red varieties, are extremely popular and do particularly well in hanging baskets and container plantings.

Spider flower (Cleome spinosa): Cleome are old-fashioned, tall and sturdy plants that grow from 36 to 48 inches. They thrive in sandy or well-drained soil and can take full sun. The blooms are prolific and vary in color from white to dark pink. The wispy blooms sway in the breeze and add movement to the flower garden. The seeds self-sow so they are likely to appear in the same spot the next year. Cleome bloom from summer through fall and are long lasting as cut flowers.

Sun Coleus (Solenostemon scutellarioides): Many gardeners think of coleus as the bulb like plants that thrive in the shade. This list refers to the group of plants known as “sun coleus.” In fact, the botanical name has been changed to Solenostemon for this family of sun loving annuals used for its colorful foliage. Trying to describe the many and varied colors of sun coleus is truly like trying to describe the sunset at the Grand Canyon. The colors are amazing. “Arizona Sunset” is one of the most popular varieties. It grows to be 18 to 24 inches tall and is very upright. It has variegated red, yellow and orange leaves and pairs beautifully with dragon wing begonias in container plantings and hanging baskets. This plant is absolutely one of the best performers in the summer garden.

Gardening during the hot months of July and August can be quite rewarding. By choosing the right plant and planting it in the right place, the summer garden can be beautiful and lush until fall. Evaluate the successes in your garden and take note of the problems or failures. Enjoy the victories and make a plan to remedy the problems using some of the suggestions above. How does your garden grow? Probably much better than you think it does! Happy Gardening!

Things to do in the Garden for July and August:

  • Monitor watering and irrigation systems.
  • Check soaker hoses to make sure they are not clogged and are still doing their job.
  • Fertilize annuals weekly and perennials monthly, both with a water-soluble fertilizer. It’s best to water in the morning.
  • Deadhead annuals and perennials. Cut some beautiful blooms to take inside.
  • Save seeds from spent perennial and annual blossoms.
  • Weed. It’s best to do before 10 a.m. or after 5 p.m. when the temperatures aren’t so intense.
  • Check for pests and treat accordingly.
  • Enjoy the garden from the comfort of your shady porch or cool house.
  • Make notes of successes and failures in the garden and plan for the fall.

Mary T. Dial, a Master Gardener and owner of the Intinerant Gardener, has been gardening in the Midlands since 1994.