I purchased several amaryllis plants and also have some from a previous year. The old ones were planted outside in the garden and fertilized. Some have bloomed but not as well as the previous year. All them were planted in pro mix and treated with Feed and Forget. They are putting our green leaves. Please tell me how to treat them this summer (if it ever comes)to restore the bulbs.
I assume that your amaryllis plants bloomed inside over the winter; once they finish blooming, cut off the flower stalks at the base, and continue to water the bulb, allowing the leaves to grow (this nourishes the bulb), and fertilize once in awhile.
Plant the bulbs in your garden in late spring, after all risk of frost has passed. You can acclimatize the plants gradually to the brighter light outdoors by moving them initially to a porch or patio before planting them. Make sure the plants get lots of sun (as well as some shade during the afternoon) and that the site is well-drained. The soil should be rich in organic matter. Fertilize them with low-nitrogen fertilizers (e.g., 5-10-10 or 6-12-12) in accordance with package directions. Give the first fertilizer “dose” as new growth starts and repeat when the flower stalk is around 6-8 inches tall, and a third dose right after the plant flowers (when you have removed the old flower heads/flower stems). Keep the plants well-watered (but not wet). If you wish, you can leave the plants in their pots and move these outside.
Amaryllis plants are native to tropical regions, so need to be taken in after the first frost. (however, some gardeners recommend bringing the bulbs in before the frost (with leaves intact). You might want to experiment, and do some each way.
Whichever method you use, put the bulbs back in pots, add fresh potting soil and bring them inside into a sunny, but cool (50-60 degrees F) room. Stop watering. The leaves will die back. If you want you can now move the plant to a dark, cool room. After a rest period of 8-12 weeks put the bulb in a south window and start watering it again. Soon you should see new growth.
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