The Dry Garden: Some sage advice for planting the right salvia in the right spot
Sages do not need fertilizer, and in fact they shrivel at the suggestion. Few other plants attract more pollinators to the garden. But one attribute above all of these should make sage not just an emblem of our past, but also a powerhouse plant of our future: Western and Mediterranean sages need little water.
This age-old adaptation for dry conditions explains in part why watery gardens have underused the plants. The leaves become blighted and roots rotted when the plants are put in the range of sprinklers.
A less remarked problem: how to gauge size when planting. All plants look small in one-gallon pots, but our best performing garden sages can run from 6 inches to 6 feet tall when mature. The trick is picking the right sage for the right spot. Some recommendations suitable for Southern California after the jump ...
Salvia spathacea, also called hummingbird sage or pitcher sage: This is the basset hound of the genus. Common in the Santa Monica Mountains, its large fleshy leaves appear from woodland mulch with rains, soon followed by large autumn and spring flowers in shades of magenta. Because hummingbird sage is rhizomatic, meaning it spreads through its root system, it can be separated and spaced according to your needs in the autumn. This means a single one-gallon plant can eventually fill a bed — a boon to landscapers on a budget. Left alone, it will spread, creating seasonal beds. Dry gardeners allow it to shrivel back to nothing in summer, but in irrigated beds, foliage and flowers may persist through summer.
Salvia sonomensis, or creeping sage, or Sonoma sage. It starts low and stays low, but single plants can branch out as much as 3 to 4 feet in diameter. Although geographical studies (and the name) indicate the native range is northern, Sonoma sage can flourish in the Los Angeles basin with little supplemental water. It’s a fine companion plant for mallows.
Salvia greggii, or Texas sage, or autumn sage. It tops out at about 3 feet tall, and when pruned during dry season it can be kept to about 3 feet in diameter. Because Texas sage is native to areas in the Southwest that get summer monsoons, it can tolerate more water than some California natives. This makes it a good choice for a low hedge around roses, whose foliage and flowers it complements and whose blooming cycle it echoes with a poignant late-autumn flush. The scarlet flowering cultivars are most common, but there are also varieties with dirty pinks and whites.
Salvia officinalis, or common kitchen sage. It does well — arguably better — when freed from the herb garden and released to a drier site. Native to the Mediterranean, this is the classic food plant whose leaves do so much fried in oil with pasta. As an ornamental, it will reach about 3 feet tall and 3 feet wide and produce repeated flushes of purple-blue flowers throughout the year.
Salvia clevelandii, or Cleveland sage. It looks an awful lot like Salvia sonomensis in a one-gallon nursery pot, but after a year in the ground, this one will be well on its way to 4 to 5 feet tall while the other will be hugging the ground. Cleveland sage is our native son — above all other salvias, inherently right for Southern California. That said, its adaptation to our dry climate has made it one of the hardest plants to transfer to irrigated gardens. It prefers good drainage, but if you resist watering it in the summer, it can withstand clay. The reward will be the most richly scented leaves and vivid indigo blooms of all sages. It partners well with the lower-growing Sonoma sage and can be used as a loose hedge. Put it where you will brush up against it.
Salvia apiana, or white sage. Like Cleveland sage, white sage is an iconic Southern California native plant. As its silver leaves branch out to 5 feet in height and diameter, it takes on a sculptural, balletic aspect that endures year-round. This Merce Cunningham quality makes it a likely centerpiece for a large, dry flower bed. Shortly after the first rains, Salvia apiana will toss out spires of white flowers that are best left to dry on the plant, where they turn into stately wands. Pruning can deform it. Wait until fall for the flowers to become so brittle that they fall off or can be clipped without maiming the plant. The stems and leaves will turn stunning shades of mauve and purple from drought stress, but unless the year is exceptionally dry, Salvia apiana needs little or no supplemental water.
Salvia canariensis, or Canary Island sage. The giant of the genus can grow from seedling to 4 feet tall in a single growing season. The silvery-green foliage is handsome, but it is the large, borderline-gaudy crown of magenta-to-mauve blooms that make it a star of spring gardens. It can tolerate some summer water. After blooming, it will die back and can be cut back to as low as 1 foot, then it will rebound the following spring. Caterpillars enjoy invading the bud-heads in spring, but resist spraying. The plant will still manage to put on a formidable show and act as a butterfly nursery. It’s also a handsome companion plant for roses and buddleias.
PLANTING AND CARE
Planting: Start now and start small. One-gallon sages planted now in advance of winter rains should be given a hole four times the width and two to three times the depth of the nursery container. Before planting, soak the hole three or four times and allow the water to infiltrate. Loosen any bound roots, then use existing soil (not garden center planting soil) to fill around the seedling. Ensure that the root crown is not buried.
Watering: Deep water at a trickle for five minutes once a week for a month, then allow the rains to take over. After that, the plant should only be watered when the leaves begin to furl with signs of stress. During summer, water only in the evening when cooling temperatures will not create the deadly combination of heat and moisture in the root zone.
Maintainence: Some gardeners will say that deadheading after fall and spring blooms can prompt a repeat flush of flowers, but this approach sacrifices the beauty of the dried florets, which can persist for months and draw birds coming to harvest seeds. In fact, the hardest thing about growing these plants successfully is leaving them alone, particularly when holding a hose.
-- Emily Green
Green's column on drought-tolerant gardening appears here weekly. She also blogs on water issues at www.chanceofrain.com.
Photos, from top: Grouped images of Salvia greggii in three colors by Los Angeles Times; Sonoma sage by Myung J. Chun / Los Angeles Times; white sage by Los Angeles Times