Above: Sansevieria cylindrica (left) and Sempervivum ‘Oddity’ (right) in an undersea-themed terrarium. Haworthias and sansevierias need much less light than other succulents and make good indoor or shade plants.
Cultivate succulents native to arid climates (which is the majority) outdoors during warm, sunny months and shelter them indoors during cold, wet months.
Water thoroughly but infrequently. Waterlogged roots may rot. Don’t use pot saucers. Let soil go nearly dry between waterings. The fatter the succulent, the more camel-like, and the less water it requires. Cacti in particular cannot tolerate overwatering. In winter most succulents go dormant; withhold water unless days are unseasonably warm.
Soil: Succulents are unfussy about soil providing it drains well. Amend garden soil and potting mixes 1/3 to 1/2 with perlite or pumice, or use a commercial cactus mix.
Food: Lightly fertilize (half-strength liquid fertilizer) in spring.
Sun: Give at least three hours of full sun daily, indoors or out, to maintain plant symmetry and color, and to encourage flowering. Protect from intense afternoon sun in summer.
Air circulation is important to prevent insect infestations. Watch for mealy bugs in leaf axils and aphids on flower buds. Control by spraying with dilute rubbing alcohol.
Temperature: The majority of succulents are frost-tender. Although they can tolerate temps down to freezing and in excess of 90 (if shaded), between 40 and 80 degrees is ideal.
Overwinter indoors. Echeverias and other rosette succulents are shallow-rooted and can be scooped from garden beds and packed into nursery flats. Provide six hours of light (fluorescent is fine and economical) daily to prevent stretching ; store between 35 and 60 degrees; and keep a fan running for air circulation. In spring, reintroduce to strong sunlight gradually lest leaves sunburn.
Most succulents dislike being cold and wet, but these can handle Pacific Northwest winters, rainfall (if given excellent drainage) and dry spells:
Sedum sieboldii, variegated
Sedum (stonecrop) — Trailing varieties are lovely as groundcovers, and in rock gardens, terraces and hanging baskets. Larger-leaved Mexican sedums (such as burro tail) are less tolerant of damp cold and should be overwintered indoors. Shrub sedums die back in winter and return in spring. All produce clusters of star-shaped blooms.
Delosperma (ice plant, above) – These cold-hardy groundcovers have satiny, daisylike flowers in brilliant hues of pink, orange, red, yellow, purple and combinations thereof.
Sempervivum (hen and chicks) — Resemble echeverias but rosettes have thinner, pointed leaves and a more compact, spherical form. Cobweb houseleek (Sempervivum arachnoideum, above) is webbed with white filaments. A similar genus is Jovibarba.
Valerie Easton’s Seattle Times gardening column, “Surprise! Some succulents succeed in Seattle” recommends my book, Succulents Simplified, and shows these photos:
I live in the Williamette Valley. I own several of your books so I know you know succulents. I have also talked to a guy at Altmans nursery in California. But I am still having problems with my succulents. I continue to have problems with root rot. We get lots of rain fall through spring & some summers can be wet as well. Temperatures are already falling to just below freezing at night. ( most nights). A lot of houses have mold problems here. I have found that cactus/succulent potting soil, no matter where it’s from does not dry out within a week or more. So if I buy sucs from California they don’t look good in no time loosing their roots to root rot. I am now taking them out of the potting soil & drying them out & repotting in a cactus mix that’s homemade in Corvallis, OR. It has much less soil, more rock & perilite. I think I’m doing better with it. Also I just learned to use tepid & not cold water.
I am very concerned about my donkey tail & was wondering if you might have any suggestions. Or any ideas that might help?
Also there are many days that we don’t have any sunshine, just grey skies.
Hi Wanda —
The secret to growing ANY plant successfully is to understand its native habitat and to duplicate that as closely as possible. The reality is that your climate is difficult for succulents. These are light-loving plants from regions with low humidity, above-freezing temps, and fewer than 24 inches of rainfall annually. So. Keep them away from excessive moisture and cold, give them plenty of sunlight (even if you have to install full-spectrum bulbs), and consider investing in a dehumidifier. They also need excellent air circulation, so a fan is a good idea, too. (Anything electric can be on a timer, so it switches the appliances on in the morning and off in the evening.) As for soil, it needs to drain quickly and go almost dry between waterings. That’s more important than what it consists of, but my preference is to amend with pumice. In your climate, I’d grow the plants in 15% potting soil and 85% volcanic rock or perlite. And because succulents really do prefer to be outdoors, move them outside on days YOU want to be outside, enjoying the fresh air and sunshine.