Getting started -- You can start your plant in a 1 gallon pot.
Soil -- Use a loose, well-draining medium. A typical mix is 1 part small orchid bark, 1 part quality potting soil and 1 part perlite or coarse horticultural sand. Or use 2 parts potting soil to 3 parts perlite (medium or coarse grade is best). Don't add lime to the mix. After filling the pots, don't compress the soil.
Watering - The roots like to be kept moist, so aim to keep the soil evenly moistened, but not constantly saturated. Don't let it dry out completely, and don't let the pots sit in a tray of water.
Fertilizing -- During periods of active growth, feed about every 3-4 months with a granular fertilizer that contains micronutrients. Follow the dosage on the package.
Climate -- Clivia robusta has similar requirements to the common Clivia. Ideal temperatures are below 85 degrees F (29°C), with nights that are cool. It's best to protect them from all frost, especially the first 2 years. Older plants can survive a few degrees of frost, but the leaves will be damaged.
Bright shade or dappled sun is best. Direct sun is fine if it isn't strong. Shade it from strong sun exposure. Over about 40% humidity is best.
Re-potting -- After 9-12 months, move it to approximately a 3 gallon (12 liter) pot. After another 9-12 months, move it to a 5 gallon pot, where it can stay until it flowers. They flower best when root-bound, so avoid using an oversized pot. Avoid repotting when it nears flowering size, since it may delay flowering.
Flowering -- It's likely that this species needs cool nights in winter to trigger flower, like the common Clivia. So once the plants are 3 years old, try to expose them to temperatures between 40 and 60° F (4-15°C) for about half the day for 4 to 8 weeks in autumn. Reduce watering slightly in cooler temperatures, but don't let the soil dry out.
If you have any questions, feel free to contact me.
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