An important factor in determining the suitability of a plant to your home and envisioning the care it will need, is to know the origin of the plant. Plants that are native to desert regions will require substantial amount of sunlight and loose, fast-draining soil. Plants from the floor of a rainforest will need some protection from strong sunlight and generous humidity.
Clivia is native to South Africa where it is largely found in low light, woodland settings. Part of the Amaryllis family, it is not a true bulb. Expanded, fleshy, lower parts of strap-like, evergreen leaves tightly overlap to form swollen bases to the foliage fans. The fleshly, thick roots can filled a pot quickly, with some roots appearing at the surface. Large umbels of flowers at the tops of solid, erect leafless stalks, are colored orange red to scarlet, or rarely yellow. Shiny, 1-inch-long red berries can be produced.
The popular Clivia miniata is a robust species with lustrous, thick, arching leaves 1½ to 2½ feet in length, 1 to 2 inches or more in width. Flowers grow up slightly off center, with each stalk carrying up to 15 trumpet-shaped flowers, each 2-3 inches in length during early spring time. Flowers are generally a combination of yellow and bright orange or rarely yellow or apricot-colored varieties. Magnificent, cultivated variants are available resulting from careful breeding and selection of superior types within the species. They are characterized by their larger umbels with more richly colored, larger, broader-petaled flowers and broader foliage.
Clivia appreciates morning and late afternoon sunlight, or dappled shade from at least midday, sun conditions that simulate their native, forest habitat. Best not to place the plant in hot mid-day sun or a southern afternoon exposure to deter sunburn and bleaching of the leaves. Indoors, place Clivia in an easterly exposure as morning sunlight is less harsh than mid-day southern light exposure. To test the light falling on the plant, if there is enough light to cast a direct shadow on the leaves when you hold your hand between the plant and the window, it is too bright. A badly burned plant can recover if moved to shade, though, can take almost a year to improve.
If southern light exposure is all that is available, a sheer curtain between the plant and the window light can work to protect from the harsh direct sunlight. Or move the plant's position back from the direct sun's range. Extremely, dark green leaves may be indicators that your Clivia is not receiving enough light though, so adjust as needed.
Clivia prefers plenty of water when in growth during spring and summer and can pretty much dry out during winter's slow growth period. When watering, do so plentifully to thoroughly moisten the plant roots and then let drain, emptying out the runoff dish after 15 minutes. Watering throughout the mix helps extend the roots throughout deeply into the medium. Gradually reduce watering in the fall and keep the plant almost dry during the rest period. Better to let the plant go to dry during its rest period. At the end of winter when flower stalks start to appear gradually increase watering frequency.
Remove accumulated dust from leaves with a wet cloth or sponge every few months to help the plant photosynthesize efficiently.
Normal room temperatures are fine for actively growing Clivia. During the six-to-eight-week winter rest period, provide a temperature just below 50ºF. To flower well, Clivia should be placed in a cool area during Fall's natural temperature drop, such as in a cool porch or near a cool windowsill that does not freeze. If not given this cool treatment flowers may be prematurely produced causing flower stalks not to rise above the foliage; too warm temperatures at this time will also shorten flower life.
Protect plants from extreme temperatures shifts of in-home cooling and heating systems.
Clivia can remain in the same container (large pot or tub) for several years (3-4), flowering best when rootbound. Repotting is needed only when signs of overcrowding, soil deterioration or poor drainage are apparent usually in late winter or Spring time just as flower stalks are developing. Plants in smaller pots (under 8 inches) will need more frequent repotting into a larger sized pot. Repot into a soil-based mixture consisting of 1 part sterilized fibrous soil, 1 part peat moss/ground pine tree bark, and 1-part coarse horticultural sand, grit and/or perlite. Orchid bark potting mixture can work. Firmly pack potting mixture around the thick roots. Repot using a strong clay type pot to support the plant. Leave a couple inches above the soil for strong growing roots pushing the plant up. If regular peat-based potting mixture is used as a growing medium, topdressing is helpful during the years repotting is not performed, Topdressing is just removing an inch or more of old potting mix on the soil top and replacing with fresh potting mixture. Topdressing can be applied in years when the plant is not repotted or has reached maximum convenient sized pot, usually 10 inches. A slightly acidic soil pH is preferred (5 or 6).
When repotting, remove the plant/ roots from the pot and old mixture around roots as gently as possible. Use a clean pot large enough to accommodate the roots, but do not over-pot into a too large container, an inch or two larger is fine. Pack the soil firmly around the plant/roots. The container should have a bottom drainage hole, larger container may need two holes. Water in well.
Every two weeks give standard or organic liquid fertilizer when flower stalks are developed half-way. Continue biweekly dilute liquid fertilizer of well-rooted specimens from Spring into Fall.
Division of large plants is practiced when new growth begins in springtime. Divide plant taking care not to damage the roots. Propagation by seed may take several years (7-8 yrs.).
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Clivias by 
