How to Bloom a Cactus
- 1). Position your cactus in a full-sun location; cacti need at least eight hours of sunlight per day to bloom successfully.
- 2). Irrigate the cactus every seven to 10 days while the succulent is actively growing. Provide approximately 1 inch of water for your cactus each time you irrigate. Allow the top 2 inches of soil to dry almost thoroughly between each irrigation to avoid overwatering.
- 3). Fertilize your cactus once a month during its active growth phase using a 1/2-strength solution of a water-soluble 5-10-5 fertilizer; regular applications of high-phosphorous fertilizer helps to promote vigorous blooming. Apply the fertilizer according to the directions on the packaging; improper fertilization can burn the cactus's roots.
- 4). Move the cactus to a completely dark room, closet or cabinet for 12 to 16 hours each day. Discontinue this step once your cactus starts to bloom.
- 5). Provide your cactus with temperatures between 60 and 62 degrees F at night; cooler nighttime temperatures are essential to stimulating the blooming process.
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