Water-Conscious Landscapes

This article appeared in the Spring 2007 issue of Texoxa Living!.

Color is the hottest trend in landscaping all over the South. But to most homeowners in our area, color means one thing—water-thirsty plants—and we all know what a fragile resource water is.

Is there a way to have it all in Texomaland? Can you punch up your landscape with high impact color, and still enjoy the satisfaction of knowing you’re a wise water steward? You can if you follow these simple steps: choose plants that are as conservative as you are when it comes to water, site them in the right spot, prepare their beds properly, and keep them mulched year round.

You’ll be surprised at how quickly plants like roses and daisies will live down their reputations as hard-to-please divas and live up to their potential for enlivening your color scheme with this simple regimen.

Choose Bright and Beautiful Water-Wise Plants

Select a palette from colorful plants that are either native to this part of Texas or have been successfully grown here long enough to be truly adapted. They are generally comfortable with our local 40-inch annual rainfall. Even in drought conditions, they require little supplemental watering. In the native group you will find wildflowers, like bluebonnet, blanketflower, turk’s cap, winecup, and evening primrose. In the adapted group lie iris, daylily, canna, larkspur, cosmos, heritage roses, and much, much more.

A third group of tough but colorful landscape standouts has exploded onto the scene in the last few years—plants developed by Texas A&M University and promoted variously as Texas Superstars, Earth-Kind roses, and SmartScape plants. When you see one of these designations on a nursery pot, you know the university has field tested the plant and found it to be adapted all over the state. It will be a good bet for landscapes that are both water wise and eye-popping.

Superstar rose ‘Knockout’ may be the most eye-popping landscape plant of all. It bears flushes of luminous red flowers, over and over again, throughout the hottest summers. Other gems in the Superstar group include ‘Texas Gold’ columbine, ‘New Gold’ lantana, and ‘Gold Star’ esperanza, which will bloom successively to keep the gleam of gold alive in your yard from March till November. ‘Moy Grande’ perennial hibiscus bears traffic-stopping flowers in the summer, magenta in hue and as big as a salad plate.

When you’re ready to choose the plants that are going to brighten your landscape, shop where you can get the advice you need about each plant’s requirements. Even the toughest plants will have one or two nonnegotiable demands.

Settle Your Plants in the Right Place

Plants can be downright picky about the relative acidity or alkalinity of the soil we plant them in. Most of our local soils are highly alkaline. Roses love them, but azaleas despise them. Redbuds thrive in them, while dogwoods curse us and die. Unless your yard lies on deep sand or loam, in which case, you can probably grow even camellias and blueberries, focus on plants that don’t demand acid soils. A trained nursery professional can guide you here.

Next, your plant will need the appropriate amount of daily sunlight. Some, like red caladiums, can handle almost no direct sun; others, including most flowering plants, must have at least six hours of it (that’s what the nursery pot label means by “full sun”). Plants don’t compromise well about this issue. Read that label, or confer with a professional, to be sure you site the plant where it receives the amount of light it needs.

The last factor to consider when deciding where to install a plant is the “wet feet” factor.

We’ve all seen this one at work. You can easily check it out during the spring wildflower bloom. Just watch where the bluebonnets cut the largest swaths of color through the landscape. You’ll notice their preference for slopes and grades, places where any rain that falls will quickly drain away and not puddle around their roots or soak in for a long stay, the way it does on deeper soils. Very few drought-resistant plants can tolerate soil that stays sopping wet for long at a time.

But no matter how tough your selected plants are, you will need to water them at least until they have established a good root system. As summer rolls by with lots of thunder and little rain, you’ll be glad if you don’t have to haul a hose too far. Be prepared to provide supplemental watering, if we have extended dry periods.

Prepare Their Bed the Earth-Kind Way

The water-wise color scheme calls for a very simple bed preparation. Once again, Texas A&M horticulturists show us the way. They call their method Earth-Kind, because it calls for all-natural materials and relies on natural processes, such as mulch that turns itself into slow-release fertilizer.

You will want to loosen the soil in the planting bed to a depth of six to eight inches, mixing two additives into the soil as you dig or till—three inches of organic compost and three more of expanded shale. If the result is a bed four or more inches higher than it was before, so much the better. You’ve improved the drainage.

Organic compost is a dark, crumbly material made by letting leaves, grass clippings, or other organic matter age until it breaks down into a rich reduction. You can buy it in bags or by the truckload, or you can make it yourself by piling up yard wastes behind the tool shed. It regulates moisture, feeds plant roots, and conditions soils, loosening tight ones and helping loose ones hold their shape.

Expanded shale is a rock material that aerates soil and helps control moisture. It is mined in Texas, ground into small particles, and fired in a kiln, whence it emerges porous and lightweight, capable of absorbing water and releasing it slowly as needed.

Gardeners sometimes get carried away while preparing beds for new plants. They want to do everything just right, and sometimes their enthusiasm leads them astray.

It’s not a good idea, for instance, to dig out all the native soil in a bed and replace it with something alien, like peat moss or sand, or even compost. Once a plant’s roots grow out of the peat moss, it will still have to contend with alkaline soil. Add sand to clay soils, and you get concrete. And nothing can live in pure compost.

Mulch, Mulch, Mulch

The last step in creating a water-wise landscape is the one that really works the magic. Done consistently, it can reduce watering needs of ornamentals by at least 70%. It also allows you to dispense with fertilizers.

Once plants are installed, cover the soil with three inches of organic mulch, such as hardwood bark or pine needles. Water only when the soil beneath the mulch is dry. Plan to keep that mulch around trees, shrubs, and perennials all year round, letting it break down naturally into compost. You’ll probably have to add more mulch three or four times a year. It will slow down evaporation from the soil and add organic matter as it decomposes, thus fertilizing the plant.

By choosing the best low-thirst plants and installing them properly, you will need to water only when the plants require it. That makes you water-wise and your landscape as colorful as you want it.

Kick-it-up Color for Low Water Usage

The dozen plants on this list are just a few of the many colorful native or adapted plants that can tolerate low-water conditions during dry periods.

All will benefit from consistent mulching and occasional supplemental watering as needed.

Purple Coneflower ‘Magnus’: perennial; full sun; reseeds; blooms two months in summer, more if deadheaded; striking pink daisies
Lantana ‘New Gold’: annual/perennial; full sun; low growing; blooms from late spring until hard freeze; bright gold
Mexican Bush Sage: annual/perennial; full sun; blooms all summer, heaviest August through October; purple spike flowers
Texas Aster: perennial; reseeds vigorously; tolerates some shade, but may be leggy and lax; blooms in fall; cut back in June to keep compact; sky blue flowers
Sweet Potato Vine: annual; full sun or part shade; no bloom, grown for brilliant foliage
Rudbeckia hirta: annual/perennial; full sun to part shade; blooms spring to summer, longer if deadheaded; shades of gold and orange
Daylily: perennial; full sun to light shade; blooms in every color but blue in early summer
Texas Winecup: perennial; full sun to part shade; reseeds vigorously; very low grower; blooms spring to summer, more if watered; burgundy colored blooms
Turk’s Cap: perennial; full sun to almost full shade, more bloom in sun; attracts hummingbirds; bright red blossoms
‘Belinda’s Dream’: rose; full sun; tea-shaped blooms, throughout the summer; fragrant; deep pink
‘Carefree Beauty’ (aka ‘Katy Road Pink’): rose; full sun; blooms in flushes all summer; may show some blackspot disease, but shrugs it off; very beautiful and tough; dark pink
‘Duchesse de Brabant’: heritage rose; multi-petaled, fragrant; said to have been a favorite of Teddy Roosevelt, who wore its buds in his lapel; full sun; disease free; blooms in flushes throughout the summer; deep blush pink
Hibiscus moscheutos: perennial (this is not the tropical or Chinese hibiscus ) small to mid-size shrub; colors from white with red eye, through pink, to glowing magenta; Superstars are ‘Flare’ and ‘Moy Grande’