Describing a plant as succulent is hardly enough to pick it out of a police lineup. The term sounds scientific but it isn't. Instead, it refers to a whole universe of plants of different genera that store water in thick stems, roots or leaves, including those in the cactus clan. Succulents vary from small-as-Tom-Thumb to big-as-Jack's-beanstalk, and grow and flower in a rainbow of shades.
But one thing succulents have in common: If the plant is not looking well, it is very likely your fault. Most of the time you can revive a succulent by changing its cultural care.
Succulent Care and Feeding
Succulents are considered low-care plants, but don't confuse that with no-care. Like all other plants, succulents have needs that you must meet if you want them to keep looking healthy and vibrant. When a plant droops, consider each item on the list and make sure the care you are offering meets your succulent's needs.
Water -- Neither Too Little nor Too Much
If your succulent droops or shrivels, irrigation may be the problem. Watering too much contributes to rot diseases. Too little water can put the plant into survival mode and prevent flowering.
Succulents have the reputation for drought tolerance because they store up water, but that doesn't mean they can bake all summer long without a drop to drink. While succulents are growing -- think late spring through fall -- you need to provide them with adequate water. "Adequate" is different depending on sun exposure and planting location. A potted succulent in full sun needs a deep, daily drink, but irrigation once or twice a week is sufficient for a plant with roots in the ground in partial shade.
Light -- The More the Better with Limitations
If your succulent looks thin and stretched out, it may be getting too little light. Succulents need light to thrive. A succulent may stay alive in constant shade but it will stretch out toward a light source to such an extent that it looks drawn. Move the plant to a location with more light or, if it's in the ground, trim overhanging tree branches to let in the light.
Most species will take direct sun and lots of it, but some cannot. For example, donkey's tail (Sedum morganianum) thrives in U.S. Department of Agriculture plant hardiness zone 11 but requires a shaded, wind-protected location.
If your succulent looks washed out or pale, it may be getting too much light. It can even scorch if it is suddenly exposed to too much direct sun after being in partial shade. In a very hot climate, plant succulents in sunny garden locations that get shade at the hottest time of the day.
Soil -- Drainage is Most Important
Succulents require well-draining soil. If a potted plant begins to wilt or suffer, fill the top of the pot with water and see how quickly it drains. Always use containers that drain or the succulent can develop rot problems. For in-ground plants, construct a basin around the plant with soil and fill it up for the same purpose.
Planted in soil that retains water, succulents quickly decline. Some species, like cobweb houseleek (Sempervivum arachnoideum) that thrives in USDA zones 5 through 8 is particularly sensitive to poorly draining soil. To increase drainage, add coarse matter like lava rock, sand or perlite so excess water drains away rapidly.
Fertilizer -- Less Is Better
Because succulents don't need heavy doses of nutrients, they generally grow best in poorer, less fertile soil. This is not true across the board though, and Firesticks (Euphorbia tirucalli 'Rosea'), the red version of pencil tree, is more tolerant of ordinary soil than other succulents. It grows in USDA zones 9 through 11.
Given their general preference for poor soil, you shouldn't fertilize succulents very often. Cactuses only require a light dose of fertilizer during late spring or summer. Pick a water-soluble fertilizer higher in phosphorus than nitrogen, and mix in twice or three times as much water as the directions suggest.
Water down fertilizer for other succulents as well, but you can fertilize them three or four times during the growing season.
Succulents generally are not troubled by serious pest infections. If you notice the cottony coverings of mealybugs or the tiny, raised spots that indicate scale, wipe the bugs off the plant with cotton dipped in alcohol.
You can keep succulents free of rot -- both fungal and bacterial -- if you are careful about succulent care. Improper watering and not enough light are major factors in rot issues.