Succulent plants are grown primarily for the structure of their water-storing stems, leaves, or roots, which give lasting interest. Flowers are a wonderful bonus, but often succulents are shy to bloom, especially if they are indoor container plants. Find out what conditions prevail in the plants' natural habitat to get clues about what growth conditions and seasonal cycles they need.
Many succulents need higher temperatures in summer to set their blooming chemistry. Climate-controlled homes do not provide the required temperature extremes. Succulents benefit from being moved outdoors for the summer months, but the move should be gradual, exposing them to more heat and sunlight over a couple of weeks until they are in partial sun and warm temperatures. Plants from cold-winter deserts need winter dormancy and cold temperatures to induce spring blooms. Put such plants in cool areas for the winter months.
Producing a flower is important to a plant because seeds are needed to perpetuate the species, so they will flower if possible. However, they need plant food to provide the building blocks for flower formation. In deserts, the soil provides proper nutrition because there is not a lot of rain to leach plant nutrients out of the soil. Under cultivation, fertilize succulents beginning in spring as the plant starts growing. Use half-strength fertilizer once a month while the plant grows, discontinuing feeding in late summer or early fall. To promote flower formation, use a fertilizer higher in phosphorus, such as 10-15-10.
Succulents need water to form flower buds and produce new growth. If they do not get it, they deplete the water stores in their tissues that they need to survive drought. As a result, they live but do not thrive. During growth periods, water plants thoroughly until water comes out of the pot's drainage holes, but do not water again until the top inch (2.5 cm) of soil is dry. Most succulents undergo dormancy for part of the year, usually in either winter for cacti or summer for plants like Lithops, and this rest period is needed to set the stage for flowering. Keep the plant drier during dormancy. All succulents need a well-draining potting mix.
Even if they are growing under a bush in nature, arid-land plants receive a lot of direct and indirect light that can be difficult to duplicate indoors. Most succulents need sunlight for half the day, preferably morning, to produce the food required for blooming. If growth is open and lax on leaf or stem succulents that should be compact, there is not enough light for flowering. If globular cacti are stretching for the sun, they will not flower. Only a few genera of succulents, such as Gasterias, Haworthias, and some Aloes, will bloom if kept in full shade. If sufficient natural light is lacking, grow succulents under grow lights.
Photo periodicity is important in setting the biological clocks of all organisms, from humans to plants. Like the Holiday Cacti (Schlumbergera cultivars), some succulents need long-night, short-day conditions plus cool temperatures to initiate flower buds. For many other succulents, the increasing day length plus warming spring temperatures signal buds to grow. Receiving supplemental light that artificially lengthens or shortens the nights can interfere with flowering.
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus