Perrenials for summer color

By Jan Pipher

Freelance Writer

‘d like something colorful I can sit inside my house and look at in August, said the customer. My uncomprehending look caused him to explain further. “I mean that I want something that blooms during the heat and doesn’t require my venturing out of the A/C to care for it.” This was as new to me as I was to Texas — didn’t everything bloom during the heat? How hot does it get down here? Well, the shopper knew more than I did that sparkling spring morning! As I soon found out, many perennials take a breather in the heat — in other words, they’re dealing with the high temperatures and lack of water by cutting back on blooms and foliage. From the end of June, with the last of the Shasta daisies and daylillies, the “goin’ gets tough” in the flower world, separating the Yankee and “old South” favorites from a unique combination of the Texas natives and hot climate transplants.

Summer color may not be your first priority, perhaps you vacation in August, or just want something that will get through the heat without raising your water bill astronomically. Planting for summer color alone could have the drawback of empty beds throughout the cold months of the year when most of these hot season perennials go completely dormant. A combination of evergreens (for winter), seasonal bloomers, and August color plants will give balance to your landscape and still cut down on your forays to the flower garden in 100+ degrees. Many of these plants you already know and pass up every spring, “Oh, I don’t like such and such. It’s too old fashioned or I can’t stand the scent, or it looks like a weed, or whatever, but remember how it blooms when nothing else will?”

Consider lantana. You can’t live without it in Texas. It’s slow to come out in the spring, making it a good companion for spring bulbs and flowers that will disappear in the heat. White and lavender trailing lantana need well drained soil; the gold mound and the bush types aren’t as fussy; and of course the native (l.horrida which is not horrid in the least) is the toughest (and tallest) of all. Lantana does have a scent — I imagine it as smelling lemony, but remember we’re talking about looking at it from an air conditioned interior not sniffing it.

Cannas pack a whole lot of tropical color to match our tropical summer temperatures. Grown from a hardy tuber, cannas will need to be thinned more often than coaxed. A little judicious deadheading will keep the tall flower stalks with multiple flowers in pinks, corals, bicolors, reds, flaming orange, or yellows coming all summer.

Another big showy plant is winter hardy hibiscus. This tall and wide bush sends up stalks after the ground warms in the spring and will continue to unfurl its “dinner plate” sized blooms of pink, white, or red blooms from early summer to the weather turns cool. The Texas Super Star program recommends three excellent choices: Moy Grande which has possibly the largest open faced bloom in the world — its pink flowers can measure 12 inches in diameter; and two equally nice deep satiny reds, Flare and Lord Baltimore. We also have a showy native hibiscus, the five petaled, red “Texas Star” which gets to 6 feet tall and is very hardy.

Rudbeckias (“Black-Eyed Susan”) and purple coneflower (Echineacea) with their daisy-like flower heads, are similar in height and growth patterns. Both are natives that can adapt to many different soils and climate and so are found growing all over the United States. After their first bloom period in early summer, if the flower stalks are cut down to the basal leaves, they will send up new flower stalks and perform superbly through the heat. Coneflower also comes in a white form which could be one way for you to extend your daisy season.

Cloth of Gold yarrow makes a dense umbel head of tiny yellow flowers on a long stem that will brighten up your beds and can also be cut for a dramatic addition to fresh and dried arrangements. This kind of yarrow does not like overwatering and would probably do best in a raised or well-drained bed if you live on the humid/wetter side of Texas.

Yellow “moonbeam” coreopsis and its new showy cultivar relatives, “limerock ruby” and pink and white “sweet dreams” are airy little border plants that will bloom all season if you can keep their feet out of the water (a well drained situation) in the spring. Lance leafed coreopsis (“sunray,” “baby sun,” “early sunrise,” etc.) are probably hardier perennials but tend to go dormant in the heat, so are more of a late spring/early summer bloomer.

imageThe butterfly weeds, Asclepias tuberosa, in orange, yellow, and yellow and red (known as Mexican oleander), don’t even start blooming until it really gets hot and then continue right up to frost. Named for the butterflies that are drawn by the large quantity of nectar they produce, these plants are a must for the butterfly garden and are a reliable for summer color as well. Another good butterfly attractor, Gregg’s Blue Mist (Eupatorium greggii), blooms in the heat and is usually covered with a cloud of bright orange Gulf Fritillary butterflies. This plant with its ageratum-like flowers does well in full sun but will go into some shade as well.

Zexmenia is a shrubby little yellow flowered bush that has to be one of the toughest natives around. It is an aggressive grower but has the fine trait of easy pullability so you can keep it in its place. Like lantana, Zexmenia hispida gets a late start, so is an anonymous nothing among all the spring bloomers but when they’re all done, Zexmenia fills their place.

The hotter it gets, the better plumbago likes it. This mounding shrub has the distinction of covering itself in small blue (not purple, not lavender but a true blue!) flowers. Plumbago also comes in a white form making it an eligible candidate for a moonlight garden.

Talking about blue that isn’t blue, pink scabiosa is pink but blue scabiosa is — you guessed it, lavender. It doesn’t matter anyway, because scabiosa is such a top performer, spring, summer, fall and winter, that you’ll want it in any color. With mounding evergreen leaves, 10″ tall scabiosa or “pin cushion plant” puts up blooms in August and all year ’round.

Several vines bloom in the heat. The exotic flowered “passion vine” in purple, bluish lavender, red, or white blooms all summer. With the additional plus of scent and edible fruit, who could fault passion vine — except, be warned, it can really cover. And so can “Sweet Autumn” clematis, climbing off the trellis and on to your shrubs, covering all with sweetly scented white flowers in late August. Perennial morning glory which comes in many colors, including a royal blue, not only covers but it positively takes over. It will look deceptively wilty during the heat of the day, but morning glory truly is the glory of a summer morning.

Usually relegated to the herb garden, white flowering garlic chives bloom heartily in August and even make a pretty, though slightly stinky, bouquet. The flattened slender vertical leaves add a different form to your garden and are edible as well.

Two small natives with somewhat similar growth habits are pink skull cap (Scutellaria suffrutescans) and red flowered rock pentstemon (Pentstemon baccharifolius). Both are evergreen and trail slightly so make perfect low maintenance perennial border plants through the heat and all year round.

imageSalvias, ranging from white, to pink, to reds, to lavender, and deep purple are old standbys for summer color. Salvia greggii will bloom in the heat but summer is not this reliable shrub’s peak season. Better is Salvia farinacea, 18 to 36 inch stalks of nice blues and purples. Or Salvia guaranetica which comes in blue (“Argentinean Skies”) to deep purple and unlike most of these heat plants, takes some shade. Or “Indigo Spires” salvia which is big (4 foot by 4 foot) but not really blue (it’s purple). This salvia is covered with honey bees all summer and doesn’t mind the heat at all.

Last, but certainly not least is ruellia — tall ruellia, short “Katy” ruellia, white ruellia, pink “Chi Chi” ruellia and plain ol’ purple — that “disobedient” fall obedient plant which keeps itself from extinction by putting up undeniably gorgeous spires of lavender pink at a frying 115 degrees! When the rest of the flower bed looks like Death Valley, there’ll be some ruellia and obedient plant cheerfully blooming away. And, that’s why I never totally weed these two weeds out, because in August I’m thankful for them — they make me look like I can garden.

Subscribe today!