They save water, need little care and seem made for parched California landscapes. No wonder so many gardeners love succulents.
With their attractive sculptural forms and wide range of colorful species, succulents offer a lot to gardeners looking for interesting drought-tolerant plants that can survive extended periods without additional water. Once established, most species need irrigation twice a month or less – or not at all.
According to industry experts, succulents are the highest growth category in the nursery business, even outpacing vegetables. Their popularity is traced not only to their potential water savings, but their space-saving ability; dwarf varieties are ideal for small gardens, patios, balconies and containers.
But before you convert your landscape to a sea of aeoniums and agaves, think about where you’re planting these beautiful succulents and the challenges they may face.
Although these are tough plants, they’re not indestructible. The biggest challenges to succulents in Sacramento? Too much water, too much sun and too much cold.
“You do have a challenging climate for succulents due to your seasonal extremes,” said Debra Lee Baldwin, author and succulents expert who has written three best-selling books, including “Succulents Simplified” (Timber Press, $24.95, 272 pages). “Succulents that don’t mind cold down to the mid-20s – such as delicate-leaved sedums and sempervivums – tend not to do well in summer heat that exceeds 90 degrees. But that’s exactly the conditions I have in my own garden, in the foothills northeast of San Diego. I grow absolutely everything, succulently speaking, but I do keep the plants’ requirements and my garden’s microclimates in mind.”
In her much-photographed half-acre garden, Baldwin has more than two decades of experience growing succulents. At 1,500 feet elevation, her garden is subject to subfreezing temperatures in winter and triple-digit heat in summer – much like Sacramento.
Baldwin has learned which plants can cope with the cold and the heat. For more tender varieties, a little protection can go a long way toward their survival.
“Most succulents that I call ‘the pretty little ones,’ such as aeoniums, jades and echeverias, do best as understory plants,” she said. “Leafy canopies and eaves provide frost protection and also shade the plants in summer. Aloes are iffy, but we can grow small, mound-forming varieties such as Aloe nobilis and blue Aloe brevifolia.”
In Sacramento, these understory succulents prefer afternoon shade, courtesy of trees, shrubs or structures. Otherwise, they can become shriveled and sunburned.
Wherever they’re planted, succulents demand excellent drainage. Too much water – or rain – can rot their roots. Come drought or El Niño, frost is a real threat every winter in Sacramento. Choosing succulents that can survive the chill is important. Often, these water-filled plants need added protection or their leaves can freeze solid and burst.
“In the open garden, I mainly grow succulents native to the Americas, such as agaves, dasylirions, yuccas and marvelous cacti – all of which need no protection or much supplemental irrigation, once established,” Baldwin said.
When envisioning a low-water landscape, gardeners often think of cacti, a large and prickly subgroup of succulents. Cacti tend to store water only in their main stem. Their sharp spines are what remain of their leaves.
“Because they can be treacherous, a cactus has to be truly gorgeous for me to grow it,” Baldwin said. But she has some favorites, such as vivid purple Opuntia “Santa Rita”; cacti covered with white filaments (Cleisto cactus strausii) or red spines (Ferocactus species) that glow when backlit; or have marvelous varigations (such as Opuntia ficus-indica “Variegata”) or spheres (like golden barrels Echinocactus grusonii) that look great when repeated in a landscape pattern.
“I’m also a huge fan of spineless opuntia, which I call ‘caressable cactus,’ ” she said, citing as examples Opuntia cacanapa “Ellisiana” and Luther Burbank’s “Avalon” cultivar. “It grows a hedge which doubles as a fire break – important when you live in a backcountry area, as I do.”
Agaves have become eye-catching focal points in many drought-tolerant gardens, but some grow better in Sacramento than others.
“Not all agaves are frost-hardy – Agave attenuata certainly isn’t – but most will go several degrees below freezing, and a few go much lower,” Baldwin said. “There are dozens of varieties, from soccer-ball-sized to behemoths bigger than Volkswagens.”
On the other end of the succulents scales are low-growing ground covers. Choose those that don’t need frost cover.
“Ground covers such as blue Senecio mandraliscae and all the ice plants do fine without protection, as does Graptoveria ‘Fred Ives,’ which evidently benefits from hybrid vigor,” Baldwin said.
If the forecast dips below freezing, be ready to cover tender succulents with frost protection or carry them to safety. From her experience, Baldwin prefers to cover her plants with old bedsheets.
“I cover vulnerable succulents growing out in the open, like larger aloes and shrub crassulas, with sheets when there’s a frost advisory,” she said. “My more tender succulents, such as kalanchoes, grow only in pots, which can be sheltered when the weather turns too hot, cold or wet.”
Rain can replenish succulents’ moisture-packed leaves, but don’t oversaturate the plants, particularly if they’re in containers. With succulents, a little water goes a long way.
“Recently, I moved my potted succulents where rain would refresh them,” Baldwin said, “but now they’re safely back beneath eaves, where they’ll benefit from warmth radiated by the house.”
Want succulents that can take the cold as well as the heat? Succulent Gardens (www.sgplants.com), which grows more than 400 species in Castroville, has these recommendations:
▪ Aloe polyphylla
▪ Jovibarba heuffleii
▪ Echeveria agavoides
▪ Agave (some species)