How to: Indoor Cactus
- 1). Place the cactus pot in a location that receives all-day sun, such as near a south-facing window. Choose a warm location with temperatures above 65 degrees Fahrenheit for best growth. Lower temperatures between 45 and 55 degrees during the fall and winter encourage tropical cacti to produce flower buds.
- 2). Water desert cacti when the top 1/2 to 1 inch of soil feels completely dry. Water tropical cacti before the top 1/2 inch of soil dries completely. Water less frequently during fall and winter when the cacti are in a semi-dormant state.
- 3). Fertilize both types of cacti once monthly in the spring and summer. Apply a soluble 5-10-5 or similar low-nitrogen fertilizer at the lowest rate recommended on the package.
- 4). Repot the cacti in spring when the base of the plant grows to within 1/4 inch of the pot rim. Plant the cacti into a pot one size larger than the old one. Use a cacti potting mixture or equal parts potting soil, peat and coarse sand to create your own mix.
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