I recently got an email question about caring for new clivia plants. Below I have just quoted the care portion of an article from GardenerHelp.com. I hope this answers the question. Gardener Help is the resource I always use. It is a collection of the files and articles that are used by Wayside Gardens call center employees when answer customer service questions.
Pot in a good garden soil with humus (leaf-mold, peat, etc.) added. A soilless mix such as Park’s Grow Mix is a suitable medium. Fertilize bi-weekly during the growing period with a fertilizer such as Hyponex or add one of the slow-release fertilizers, such as Mag-Amp, when potting, in as much as this will furnish the necessary nutrients for one growing season. Re-pot once every 4-5 years and allow the plant to become pot bound. The resting period is October through January. Water sparingly during this time without allowing the leaves to wilt, keep at a cool 50 degrees and do not feed. In January when the growth starts, return to more light, high humidity and 65 degrees. During the growing season water well, then allow the soil to approach dryness between waterings. Clivia blooms best when pot bound, in light shade and when it has had cooler (50 degree night-time temperature) winter temperatures. Do not dry completely during the resting period and do not cut off the foliage as with Amaryllis. Clivia enjoys a high humidity during the growing period and a syringing of the leaves after flowering has ceased is beneficial.
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