By Jay White
June is a tough time for me. As someone who likes to be outdoors, I know that our oppressive summer heat is about to make it a lot less enjoyable. While the heat is a bit of a problem for me, there are ways to adjust. I can always get up earlier or wait until evening to do my gardening chores. My plants, on the other hand, are stuck wherever they are and they have to either adjust to the heat or die. Many of the beautiful flowering plants that we love to grow in the spring won’t survive until July, thanks to our extreme climate, so it can become a bit of a challenge to keep our beds and borders looking alive, vibrant and inviting.
I have struggled with this issue for years. Every year, after the snapdragons were gone and the petunias were fading, I would head to the nursery and ask for recommendations of plants that could provide some color during our hottest months. Sometimes the recommendations paid off. However, most times they didn’t. After several years of this trial-and-error method, I had spent a lot of money and wound up with a very short list of plants that could really take the Texas heat.
One of the benefits of writing for this magazine is the opportunity it affords me to get out and talk to really great gardeners all around our great state. Last year, I was talking about my search for no-fail summer color with Morgan McBride of Tree Town USA. Before he started selling trees, Morgan worked as a landscape maintenance supervisor for more than 20 years in the Dallas/Ft. Worth area. According to Morgan, his main customers during his landscape-maintenance career had been large apartment complexes. He explained that, while these businesses wanted attractive landscapes, they wanted them at the lowest cost possible. They didn’t want huge water bills and they didn’t want to pay high maintenance bills either. To fill these requirements, Morgan’s firm relied on three very common plants to ensure colorful commercial landscapes throughout the hottest parts of summer — sweet potato vine, purple fountain grass and lantana.
I learned three very important things from that conversation with my friend. First, I finally understood that color does not have to mean flowers. No plant packs more color into a landscape than the foliage of the many varieties of sweet potato vine. Second, there are some very lovely and very tough flowering plants (such as lantana) that are well adapted to our climate. And finally, I learned that landscaping with these plants that thrive in the heat will actually save you money. They are perennial, so there will be no need, or at least a reduced need, to plant annual color plants. Plus, all of these plants will look great with minimal care and water.
Since I learned so much from my short conversation with Morgan, I decided to reach out to another professional landscaper to see if she would share her list of no-fail summer color plants. Melissa Flowers is a designer for Glasco & Company Landscaping in Brenham. Glasco is the leading landscape company in Washington County for good reason. They specialize in high-impact landscapes that use a variety of drought-tolerant Texas-tough plants. They count Bluebell Creameries among their many clients.
Melissa echoed Morgan’s sentiments and greatly lengthened my list of plant material. According to Melissa, there is a Texas-tough option for just about every landscaping need. There are tall spiky flowers and low-growing groundcovers that explode with flowers. There are even options for shade.
Purple fountain grass (Pennisetum setaceum ‘Rubrum’). Purple fountain grass is one of many grasses that do well in our climate. However, it is the only one that will add a lovely burgundy color to your landscape. Combine the striking color of the foliage with its lovely and graceful flower spikes, and you have a very showy and useful plant that can be used in mass, as a specimen and even in pots. Purple fountain grass is a perennial grass. You can grow it from seed, but it is easiest to grow from transplants. The leaves of purple fountain grass start out green in the spring and slowly turn to burgundy as the season progresses. The rounded form will stay lovely until the first freeze. At that time you can shear it almost to the ground and then wait for it to start blooming again as soon as temperatures warm up in the spring.
Sweet potato vine (Ipomoae batatas). There is a phrase in the landscape industry called “60 MPH Color.” When landscapers use this, they are referring to plant installations that are so colorful that people driving by at 60 MPH will notice them. If you want some 60 MPH color in your landscape, then sweet potato vine is the plant for you. With its rapid growth rate and varieties that come in colors that range from almost black to the brightest chartreuse, there is no better way to bring a lot of color to your summer landscape than with this cousin of the edible sweet potato. The vines of this plant grow from a tuber (or bulb). Plants that grow from tubers are generally very durable plants and sweet potato vine is no exception. Sweet potato vine has two traits that I really love. It is incredibly easy to propagate and it tells you it needs water when the vines start wilting. If you want more vines, simply snip off a piece and root it in water. Sweet potato vine is great as a ground cover, spilling over a wall or tumbling out of a pot. If you live where winters are cold and wet, you can dig up the tubers and store in sawdust for next year. Otherwise you can leave them in the ground for years of beautiful foliage.
Coleus (various species). Very few plants have been hybridized more than coleus. Thanks to the work of plant breeders around the world, you can find coleus in just about every color and color combination imaginable. You can also find varieties for sun and shade. I love coleus and grow several varieties every year. I love these plants because they are so pretty and they truly seem to get bigger and prettier as the temperature rises. I also love them because they are one of the few plants that you actually have to work very hard to kill. If you forget to water your coleus they will wilt down pretty quickly. However, you can take some wilted coleus, trim them up a bit, water them and watch them miraculously bounce right back. Coleus work as well in the ground as they do in pots. Group them together for a very colorful display.
Artemisia (var. ‘Powis Castle’). Artemisia is a woody perennial plant that is known for its gray, feathery foliage and its distinctive smell. There are many artemisias out there, but the variety ‘Powis Castle’ is the best one for most of Texas. Powis Castle loves full sun, high heat and well-draining soil. A single plant will create a silver mound that is three feet tall and five feet wide in a single season. With its lovely silver-gray color, ‘Powis Castle’ is the perfect companion for plants in a variety of colors. It is lovely when paired with pink ‘Knock Out’ roses or pink antique roses like ‘Old Blush.’ I use it at the base of my bottle tree and paired with Mexican petunia (Ruellia) and zinnias. Artemisia is easily rooted from green cuttings or by securing new growth to the ground. If you don’t need this gray leafed plant in your beds, plant it in or around your chicken coop. The chickens love to rub around on it because the essential oils that create its strong scent are a natural lice and mite repellent.
Caladium. Caladiums were introduced to the U.S. at the Chicago World’s fair in 1893. Ever since then, Americans have been growing these fabulously beautiful foliage plants under trees and in other shady spots. While people have enjoyed the brightly colored leaves of these bulbs for years, their durability is seldom talked about. In the warmer parts of our state, these dependable bulbs can survive and thrive in shady parts of our landscapes for years on little more than normal rainfall. Because of their beauty and versatility, breeders have now created caladiums that can take full sun. There are even varieties that can be grown as house plants. If you live in the colder parts of the state, dig your bulbs up each year and store in damp sawdust. If you do this, you will be able to enjoy their bright foliage for many years.
Salvia greggii. There are many types of salvia that thrive in our climate. One of the more colorful and more reliable is Salvia greggii. Salvia greggii is a woody, bushy perennial that gets about three feet tall. Its upright branches are covered in little muted green leaves, but the little flowers of this hardy plant are what make it a standout in the summer garden. Salvia greggii comes in many colors, including red, white and pink, and there are other variants available. A red variety called ‘Cherry Chief’ is one of my favorites. However, I am also fond of a variety called ‘Hot Lips.’ ‘Hot Lips’ is primarily red but, as the spring progresses, the flowers become red and white. Some salvias have a reputation as invasive. I have the native Salvia coccinea and it is invasive. Salvia greggii is not. It is a mannerly bush that stays where it is planted. Salvia greggii can be almost evergreen in the lower parts of the state. If it does freeze, shear it back to about 4” in the winter. It will bounce right back in the spring. Besides its almost year-round flowering, the best thing about Salvia greggii is the fact that hummingbirds absolutely love it.
Salvia leucantha. Talk about a showy plant! Salvia leucantha is commonly called Mexican sage or Mexican bush sage. This salvia can make mounds five feet wide and five feet tall of the most beautiful purple-blue flower spikes imaginable (there are also white varieties). The flowers and leaves of this plant are soft and fuzzy. In fact, it is hard to walk past this one without running your hands over it. It is also a hummingbird magnet. All salvias grow in the same way. They have flowers from spring to the first frost and then need to be cut to about 4 inches after they freeze. Also, some folks say that they attract mealy bugs and aphids. While that may be true, I have not had any significant problem. Mexican bush sage will also spread by rhizome and seed. I would not call it invasive, but it will move around if you do not stay on top of it. If you love the look of Mexican bush sage but do not have the room for a huge plant, you can get the same result with a hybrid salvia called ‘Indigo Spires.’ This plant packs all of the punch of Salvia leucantha but only gets about 18 to 24 inches tall.
Hymenoxys (four-nerve daisy). This member of the aster family is truly tough as nails. If you have an area that needs some color but you cannot get a water hose to it, then this is the plant for you. Four-nerve daisy thrives on minimal irrigation. In fact, its water requirement is so low it is often used in cactus gardens and other Xeriscapes throughout the Southwest. Because of this, it is a great plant to put out at your gate or entryway. Hymenoxys produces quarter-sized, yellow daisy-like flowers from spring through the hottest parts of summer. Flower production actually declines as the temperatures drop in the fall. When this plant is massed, it is truly beautiful.
Zexmenia. Hymenoxys has a cousin called zexmenia that is similar in appearance and growth habit. It is also a great plant for low-water locations. If you want to bring a large swath of color to a part of your landscape that has no irrigation, plant a few zexmenia plants and then wait a couple of years.This tough perennial will grow and prosper in both sunny and part shade locations.
Blackfoot daisy (Melampodium leucanthum). Blackfoot daisy was the first low-water, perennial flower that I learned about. This low-mounding plant will create compact little bushes covered in small white flowers with yellow centers. The plants will quickly grow into lovely mounds that are about 12 inches high and 2 feet wide. Blackfoot daisy loves the hot sun. One of its common names is rock daisy, and it really will grow between rocks that get very hot in the Texas sun. Like all of these perennials we have discussed, Blackfoot daisy needs good drainage. However, it does seem to enjoy soil that has been well worked with compost. If you go to the nursery to buy this plant you may be tempted to pass it up. It tends to look thin and “scraggly” in its four-inch pot. Do not let that fool you. That ugly little plant will quickly turn into a carpet of lovely little white flowers that smell faintly of honey.
I don’t know if I am just getting older or if there is actually something to all of this talk of climate change. Whatever the reason, each year our summers seem to get hotter and drier. Combine this with a constant increase in our state’s population and I am convinced that it will not be long until we are all going to be forced into growing tough, low-water plants in our yards and borders. Luckily there are several tough plants out there that really can thrive in our hot, dry climate. This year, when your snapdragons die and the petunias fade, why not try some of the Texas-tough options discussed above? They will reward you with lower water bills and years of beautiful color.