How to Grow Amaryllis Outside

Blooming amaryllis.

A tropical, frost-tender plant from South Africa and the Caribbean, the amaryllis or hippeastrum bulb can be grown outside only in USDA planting zones 8 to 10. If you are lucky enough to live in such a climate, the amaryllis will provide a spectacular floral display in varying shades of pink, red and white. High-quality bulbs can produce as many as six blooms on a single stem and provide blooms for up to 75 years.

Things You'll Need

• Amaryllis bulbs
• Low-nitrogen fertilizer
• Trowel or bulb auger

Instructions

1. Prepare your garden soil. Amaryllis prefers a soil rich in organic matter but should do well in any average garden soil as long as it drains well and provides adequate sunlight.

2. Plant the bulbs about a foot apart. The ideal time of year to do this in most locales is late September or early October. Use a trowel or bulb auger to prepare your planting hole. Barely cover the tops of the bulbs with soil and then mulch to conserve moisture and suppress weeds.

3. At the first sign of growth, apply a low-nitrogen fertilizer in the ratio of 3 lbs. per 100 square feet of planting ares; too much nitrogen encourages leafy growth instead of bloom development. Apply a second application of fertilizer when the stalks are 6 to 8 inches tall. Once the planting is established, reduce the fertilizer ratio to 1 1/2 lbs. per 100 square feet.

4. Maintain adequate moisture. The amount and frequency will vary depending on each individual location. Amaryllis does not like to be water-logged, so be careful not to overwater.

5. Monitor for pests and disease during the growth and bloom period. Stagonospora, also known as red blotch or fire spot, is a common problem affecting amaryllis. Treat it with an appropriate fungicide if it becomes a problem. Insects such as grasshoppers, thrips, mites and mealybugs can cause problems as well. If caught and treated early the damage will be minimal.

6. After the bloom fades, cut off the flower stalk leaving 2 inches. The remaining foliage is necessary for regenerating the bulb for the next year. This is a good time to apply a third application of fertilizer.

7. Maintain the planting. Once established, your amaryllis should get into a natural cycle of blooming every April. Given a light fertilizer every March and June and kept well-watered and weed free, your planting should provide you with years of beautifully blooming flowers.

Tips & Warnings

• After several years your planting my become overcrowded. This is a sign that your bulbs should be separated and replanted. In October, carefully dig up the bulbs, separate the new bulblets that have formed and replant in the desired location.

References

• Floral Art Mall: Amaryllis
• AA Florist: Growing Amaryllis Bulbs Outdoors