Green Gardens Under Rainless Skies By Scott Ogden With droughts and water shortages becoming commonplace features many gardeners are wondering which plants will make good choices for their gardens. It's not so much survival that's at issue; there are many plants (including nearly all the native flora) that seem to survive occasional droughts. It’s just that most of these look the worse for wear. The real question is, “What can I plant that will keep my garden looking lush and green in July, even if it doesn’t rain and I can’t water?" This is a serious challenge, to be sure. Yet, a surprising number of plants stand ready to meet it. The first acquisition for any drought challenged garden might be to place some tough trees to assure a measure of shade. For this purpose pines like the native loblolly pine (Pinus taeda) are unsurpassed, making tall canopies that supply generous filtered shade, and rooting deeply to make gardening easy beneath. Many oaks are also remarkably tough and drought resistant; the coarse-leafed bur oak of the prairies states (Quercus macrocarpa) is especially rugged, eventually growing to majestic proportions and supplying crops of huge, scale-cupped acorns each fall. Exotic trees like Chinese pistache (Pistacia chinensis), with a rounded canopy of feathery sumac-like foliage that turns a spectacular red-orange in fall, and the umbrella-shaped Chinaberry (Melia azederach), with fragrant lavender flowers in spring, glossy fern-like foliage in summer, and golden berries and leaves in the fall, will make fast growing, drought tolerant trees even on thin, rocky soils. Goldenrain tree (Koelreuteria paniculata) affords another rugged subject, with unusually divided dark green foliage and branched panicles of small golden flowers that ripen to papery lantern-like seed capsules. These small trees seem to relish drought, retaining their rich, lush green foliage whether it rains or not. Among flowering trees the same might be said for several selections of redbud from the Southwest. ‘Oklahoma' (a rich wine-purple), ‘White Texas’ (with creamy white flowers), and ‘Traveler’ (with a weeping habit) are all selections of Cercis canadensis var. texensis, the Texas redbud, and all three have glossy rounded leaves that hold up in the worst dry weather, even in full sun. Another small native tree or large shrub, the Southern or rusty blackhaw (Viburnum rufidulum) also laughs off drought, displaying white flowers in spring and rich glossy foliage in summer that turns burgundy in fall as a foil for steel blue berries. Evergreen shrubs provide much of the structure in gardens, and here the choices of drought-enduring materials are also wide. Most hollies are very tough, with good glossy foliage even when they are not in active growth. The native yaupon holly (Ilex vomitoria) is versatile and popular in its rounded dwarf form, ‘Stokes’. Other lush-looking evergreens with remarkable drought resistance include boxwoods like Buxus microphylla ‘ Wintergreen’, firethorn (Pyracantha coccinea), and feathery conifers like the oriental arborvitae (Platycladus orientalis) and junipers in varieties too numerous to count. One of the most refreshing of these, ideal for reviving a drought-stressed landscape, might be the cool blue creeping shore juniper, Juniperus conferta ‘Silver Mist’. An unusual “shrub” native to the Mediterranean deserves special mention: the Alexandrian or poets laurel (Danae racemosa) is a distant cousin of asparagus with flattened leaf-like stems (called “cladodes”) that resemble the leaves of a bay. It makes a choice dwarf evergreen in partial or full shade, impervious to drought, with slow-growing glossy foliage and red-orange berries in the fall. Some of the most verdant plants in any summer landscape are ornamental grasses and many of these are among the most drought resistant. The waving blue-green clumps of switchgrass (Panicum virgatum) revive any dry landscape and may be had in several selections ranging from 3-6’ in height, all with ornamental seed heads in the fall, followed, in many cases, by blushing red leaves. Inland sea oats (Chasmanthium latifolium), little bluestem (Schyzachirium scoparium), feather needlegrass (Stipa (Nassella) tenuissima), and blue Lyme grass (Elymus arenarius ‘Findhorn’) all hold up superbly under dry conditions and give freshness and movement to a garden. Finding colorful flowering plants for a drought-afflicted garden might seem like an unrealistic challenge, but there are choices here, as well. Among annuals, tried and true varieties like bachelor’s button (Gomphrena spp.), purslane (Portulaca cvs.), narrow leaf zinnia (Zinnia angustifolia) and several lantana varieties seem to bloom whether it rains or not. Perennials like salvias, verbenas, wild indigos (Baptisia spp.), Mexican petunia (Ruellia brittoniana ‘Chi-Chi Pink’), purple heart (Setcreasea pallida), hybrid oregano (Origanum ‘Hopley’s’), pink skullcap (Scutellaria suffrutescens), Arkansas blue-star (Amsonia hubrechtii), and aromatic aster (Aster oblongifolius ‘Raydon’s Favorite’) can guarantee a lush display of bloom and texture over a long season. In shaded gardens leafy plants like bracken fern (Pteridium aquilinium), the newer hybrids of Heuchera americana, lungworts (Pulmonaria longifolia cvs.) and mondo grass (Ophiopogon japonicus) can maintain a lush appearance when other perennials fail. Of course, gray-leaved shrubs like artemisia, dusty miller, and lavender accept dry conditions and evergreen perennials like rosemary and Jerusalem sage can be called upon to keep a garden well furnished in drought. But these, and other drought hardy flora like pomegranates, chaste trees (Vitex agnus-castus), yuccas, figs, sotols (Dasylirion spp.), agaves, and the hardy spineless prickly-pear cactus (Opuntia ellisiana) will suggest a Mediterranean or dry-climate garden if used exclusively. Inherently verdant materials like bamboos or hardy dwarf palmettos (Sabal minor) and needle palms (Rhapidophyllum hystrix) make more appropriate choices if a lush, green garden is the goal. Finally, when the rains do come it’s great to have some opportunistic plants to respond and get the garden blooming in a hurry. Crinum lilies, with their massive fountains of foliage and tall stems of fragrant lily-like blooms are perfect for this, as are rain lilies (Zephyranthes spp.), tiny crocus-like cousins of Amaryllis. These subtropical bulbs will come into bloom in just a few days or weeks following a summer thunderstorm and can do wonders in reviving the spirits of a drought-plagued planting. By taking advantage of a wide range of plant materials such as these, keeping a garden lush and intriguing under drought conditions can be a realistic achievement. Light and Verity By early January several freezes will usually have singed lawns and prairies around Austin to various shades of straw. Late perennials will be collapsed in blackened masses along with their spent blooms. Even the amazingly tardy foliage of the local oaks (often still gloriously burnished red in December) will have released from gnarled twigs, tumbling to earth in piles of drab gray-brown. Mid winter in central Texas seems as lifeless a moment of the year as it does in many other parts of America. Yet, there is an epiphany here for those who remain alert. In a superb expression of nature’s irony, the desolation of the season brings with it the most intimate ally of beautiful gardens: magnificent light. Most of the year, it should be remembered, the quality of sunlight here offers all the charm and subtlety of a plaza in Cairo (roughly the same 30 degrees N latitude on the globe). Like overly well-read gardeners anywhere, Austinites may be tempted to reproduce the delicately blended floral joys of Giverny (about the same latitude as Bangor, Maine) or the rustic beauties of Tuscany (roughly equivalent in latitude to Albany, New York). In the laser-beam illuminations cast by the Texas sun these efforts invariably fall short, with floral colors clashing inharmoniously or fading pathetically, and many plants simply incinerating in the blast furnace of late summer. Even the architectural Italianate garden loses much of its appeal when it feels like Kuwait City outside. Most Texans will have given up these attempts just about the time the gentle, low-angled light of winter arrives and actually makes such dreams possible. The peaceful suffusions of the January sun give even simple garden compositions the power and warmth of a Vermeer painting. A simple clump of papwerwhite narcissus (Narcissus papyraceus) will reflect this winter light like silken stars. Other early bulbs like the old heirloom Narcissus italicus and the Chinese sacred lily (Narcissus tazetta v. orientalis) enliven the cool air with warm tones of eggshell and linen, as they offer pungent fragrances. Gray and silver foliage brings unparalleled illumination at this season, and giant lambs ears (Stachys byzantina ‘Countess Helene von Stein’) can make a beacon in borders with its plush reflectivity. Common mulleins (Verbascum thapsus) luxuriate in felted majesty, collecting dew and frost on winter mornings to add to their sparklings in the winter sun. Arizona cypresses (Cupressus arizonica ‘Carolina Sapphire’), with pungent blue branches and vague turpentine aromas, make brilliant sentinels. Grasses make the most of the winter light by transmitting the low rays of the sun through their thin, slender foliage. Mexican feather grass (Stipa (or Nasella) tenuissima) and bamboo Muhly (Muhlenbergia dumosa) are two of the best; capable of surviving the annual summer roasting they must endure here, as well. Lastly, the surprising frost hardy Australian cycad, Macrozamia johnsonii, offers magnificent 12’ rosettes of feathery chartreuse leaves, clustered like crowns of a date palm so that each plume gracefully weeps and twists, catching the best of the sun as it moves across the southern sky. Like the grasses, these ancient plants take all the heat and drought that the rest of the year can (and will) throw at them. Plant Profile: Algerian Iris (Iris unguicularis) The most exquisite midwinter bloom Texans may hope to enjoy belongs to a clumping iris (once called Iris stylosa) with luscious, pale periwinkle-blue flowers that resonate in winter light, appearing in flushes from December through February. Fast drainage and dry, rocky conditions are welcome, but don’t seem essential. Sun or part shade will do. The grassy foliage remains handsome most of the year, but sometimes hides the short-stemmed blooms, inviting gardeners to inspect clumps for flowers every few days. Plants For The Dry Years Common Name Botanical Name White & Navy Texas Bluebonnet Lupinus texensis Gaura, Plume Poppy, and Cosmos Gaura lindheimeri & Macleaya sp. Dahlberg Daisy Dyssodia sp. California Poppy Elsholtzia californica Pink Evening Primrose Oenothera speciosa Sundrops Calylophus drummondianus Silver Fluttermill Oenothera macrocarpa v. incana Purple Coneflower Echinacea purpurea Hill Country Penstemon Penstemon triflorus Sweet Alyssum & Silver and Gold Mum Ajania pacifica & Lobularia maritima Mountain Sage Salvia madrensis Big Red Sage Salvia darceyi Pink Skullcap Scuttellaria suffrutescens Arkansas Blue Star & Aromatic Aster Aster oblongifolius & Amsonia hubrechtii Red Batchelor’s Buttons Gomphrena haageana Blue Mistflower Eupatorium odoratum Gayfeather Liatris sp. Cigar Flower and Compact Ceniza Cuphea micropetala & Leucophyllum Orange Bulbine (Bulb-Eye’-Nee) Bulbine ‘Hallmark’ Trailing Lavender Lantana Lantana montevidensis Hybrid Verbena Verbena x teasei Pink Wood Sorrel Oxalis crassipes Oxblood Lily Rhodophiala bifida Velvet Creeper Tradescantia sillamontana Purple Heart Setcreasea pallida Early White Flag Iris albicans Algerian Iris Iris unguicularis Spuria Iris Iris spuria hybrid Cretan Tulip Tulipa bakeri ‘Lilac Wonder’ Lady Tulip Tulipa clusiana ‘Lady Jane’ Early Red Tulip Tulipa praecox Virgin’s Spray Ornithogalum narbonense Spring Starflower Ipheion uniflorum Byzantine Gladiolus Gladiolus byzantinus ‘Cruentus’ Narcissus Narcissus italicus Fall Crocus Crocus goulimyi Dwarf Myrtle Myrtus communis ‘Compacta’ Wall Germander Teucrium chamaedrys Silver Germander Teucrium cossonii Love in a Mist Nigella damascena Hybrid Oregano Origanum x ‘Hopley’s’ Oleander Nerium oleander ‘Single Hardy Pink’ Jerusalem Sage & Corn Poppies Phlomis fruticosa & Papaver rhoeas Artemisia and Drumstick Allium Artemisia ‘Powis Castle’ & Allium Rosemary Rosmarinus officinalis Hacienda Creeper Parthenocissus cv. ‘Rancho Viejo’ Orange Crossvine Bignonia capreolata ‘Tangerine Beauty’ Variegated Giant Cane Arundo donax ‘Variegata’ Mexican Feather Grass and Mealy Sage Stipa (Nasella) tenuissima & Salvia Canada Wildrye Elymus canadensis Four O’clocks Mirabilis jalapa Milk and Wine Lily Crinum ‘Empress of India’ Texas Ash Fraxinus texensis Texas Redbud Cercis texensis Arizona Cypress Cupressus arizonica Live Oak with Oxblood Lily Quercus fusiformis & Rhodophiala Mexican Plum Prunus mexicana Possumhaw Ilex decidua Rusty Blackhaw Viburnum rufidulum Bourbon Rose Rosa x borboniana “Maggie” Mountain Laurel Sophora secundiflora Redberry Juniper Juniperus pinchotii Bermuda Palmetto Sabal bermudana Barbados Pride Caesalpinia pulcherrima Convent Ceniza Leucophyllum frutescens ‘Convent’ Red Yucca Hesperaloe parviflora Sacahuista or Beargrass Nolina texana Pale-leaf Yucca Yucca pallida Mountain Maguey Agave montana Prickly-Pear Opuntia sp. Hen and Chicks Echeveria runyoni Little Gray Stonecrop Sedum potosinum Hinckley’s Columbine Aquilegia hinckleyana Palmer’s Stonecrop Sedum palmeri Shrimp Pink Tropical Sage Salvia coccinea ‘Jones’ Pink’ Naples Onion Allium neapolitanum Chinese Ground Orchid Bletilla striata Purple-leaf Wood-Sorrel Oxalis regnellii ‘Triangularis’ Mixed Water Lilies Nymphaea spp. Return to 2001 Oktober Gartenfest Table of Contents