By Brad Wier. If you’re swapping out winter bedding for summer color this month, consider this: Changing everything to new bedding plants can be daunting during an extended drought.
In the heady days of early sprinkler irrigation, many a homeowner (and many HOAs and businesses) once used masses of begonias, coleus, petunias, pentas and zinnias to accomplish big bright seas of color in the summer landscape. But over the last few decades, many landscapers have reduced or entirely ditched changing out seasonal color in favor of incorporating more long-lived perennial displays.
That’s because keeping a fresh 4-inch bedding plant from drying out can be difficult during a summer drought. Very few annuals coming out of 4-inch pots have enough roots to be considered drought tolerant. Without careful watering over the first few weeks they can be wiped out by just a few scorching hours of 100 degree temperatures. That may be why sweeps of textured perennials have started to become more prominent than old-fashioned sweeps of short-lived annual color.
With the severe drought continuing and Stage 2 watering rules entering their third summer, it makes sense. Another benefit of using perennials? They don’t need to be changed out and watered in every season. Just wait for them to return on their own every summer — it saves water, time, stress and money.
If you’re looking for examples of spikes and mounds in action, they’re everywhere in commercial developments both in midtown San Antonio and north of Loop 1604, where new landscapes need to look marketable.
If your own winter annuals are past their peak and you’re preparing to swap out landscape beds for summer, there’s no need to reinvent the wheel. To fill up a big area in a hurry — especially in the sun — remember the rule of spikes and mounds. Once you learn this concept, you’ll realize it’s quite common in successful southwestern landscape design.
Here are a few tips to help you along.
Plant selection. Leaves that can resist drying sun and wind tend to be thin and fairly small with minimal surface area. Many are also pale in color, and waxy, fleshy or fuzzy to the touch — all features that help them retain water in hot weather and drying winds.
Design. Incorporate these bulletproof features into easy landscape design by laying your plants out in groups of “spikes and mounds.”
In design, “spikes” are plants with long, thin leaves: muhly grass, feathergrass, iris, sotol, yucca, bulbine. With long, thin leaves, they’re able to survive extreme heat without losing so much water. They can be used as single specimens, or in sweeps to add instant architectural impact to any outdoor scene. Generally, they’re some of the most ornamental of all xeriscape plants.
“Mounds,” on the other hand, are sage-like plants with little fuzzy or waxy leaves (good for retaining water) and dense, sprawling shapes that help shade their own roots. There are dozens of salvias to choose from, along with lantana, Texas oxeye, skullcaps, trailing rosemary and plumbago. Although short in stature, flowering mounds provide a big bang in terms of summer color and can fill up a lot of space in a hurry.
Remember, a common shortcoming in xeric design is using too many mounds: all those tiny little leaves can get a little monotonous without some contrast, especially the ones that turn brown in winter. To create additional texture, pair spikes and mounds with a few agaves, shrubs or trees. (And for bigger color, throw in esperanzas or pride of Barbados.)
The rule of threes: Remember when you’re laying out plants, use odd numbers — groups of three, five and seven — and group similar plants to add pulse to a large area.
Like many landscapers who have made the switch, you may find that the ease of changing out and caring for a few hardy one-gallon plants beats the expense of watering in a sweep of 4-inch annuals. Just don’t forget to mulch!
Brad Wier is a SAWS conservation planner. Years in South Texas landscaping and public horticulture gave him a lasting enthusiasm for native plants that don’t die when sprinklers — and gardeners — break down. He’d rather save time and water for kayaking and tubing. He is a former kilt model, and hears hummingbirds.