How to Plant and Grow Stunning Amaryllis Flowers Outdoors
Most people think of lily-like amaryllis flowers as Christmas-gift plants, and they do make excellent gifts. But many of them can be grown outdoors year-round in certain zones for gardeners who simply want to beautify their garden. They are available as singles and doubles and come in reds, pinks, salmon, near-orange, creamy yellow, and white—all with some outrageously beautiful designs. As a bonus, some are even fragrant. With a minimal amount of care, they will come back year after year.
Since amaryllis bulbs are native to South America, they are tropical and can be grown successfully outdoors in very warm and frost-free zones.
Where, When, and How to Plant Bulbs
Where: If you are in USDA growing zones 9–11, you are in luck if you are planning to plant your amaryllis bulbs outside. Amaryllis bulbs need to be planted in an area where they will receive full sun. They can grow in areas of light shade, but in full sun you can expect them to develop stronger stems and more flowers. One note of importance is that you should never plant amaryllis bulbs in soil that gets soggy, as the bulbs will most certainly rot. Approximately six hours after a hard rain, if you still see water puddles, you will need to choose another location.
When: Amaryllis can be planted from September through April in warm weather climates, although most people prefer to have theirs in the ground by late October.
How: The area in which you plant amaryllis bulbs must drain very well. Once you have the ideal place in mind for planting, determine the soil's pH, which will help you in determining if your soil is sand, silt, clay, or loam. Once determined, and if necessary, amend it a few months prior to planting, as amaryllis grows better in a soil mix that is high in organic matter. You could use two parts of loam soil and mix in one part perlite to one part of well-rotted manure. If you don't have manure available, try using peat, leaf mold, or compost; or one part loam, one part sand, and one part compost.
Dig holes deep enough that will allow you to plant the bulbs with an inch of the bulb above the surface of the soil. Plant the bulbs about 8 to 12 inches apart and water well, soaking the soil so that it settles around the bulb. After the initial soaking, water very sparingly, as the bulb doesn't require more moisture until there is growth to support (keep the soil barely moist until you begin to see leaves). You can usually expect your amaryllis to flower in mid-spring, although occasionally flower stalks will develop in the fall, usually during the first season.
Once the plants have sprouted, you can begin watering more, but don't let the soil get soggy. The leaves of amaryllis plants will grow through the summer and disappear in the fall if the plants are dried off; otherwise, some of the foliage will remain.
Continued Care for Amaryllis
If you have a flower bed that is cared for well, you can expect your amaryllis bulbs to remain in the ground and provide you with beautiful flowers for several years.
After their winter bloom, reblooming can be achieved by cutting off the tubular flower stems to within an inch of the top of the bulb when the blooms fade. Leave the foliage, however, to continue growing. Then, water as usual and apply water-soluble fertilizer every four weeks. Your plant should grow a number of leaves during the spring and summer. This will help the plant produce energy for the next year's bloom.
Overwatering is the fastest way to kill amaryllis bulbs.
Dividing Amaryllis Bulbs
Amaryllis bulbs do not need to be divided as often as most other bulbs. But plant division is not only a way to control amaryllis colonies, it also helps to keep your plants healthy. If you decide it is time to divide them, this is the proper way to do it:
- After the leaves die back, dig up the bulbs and gently separate the offsets from the parents.
- Replant the bulbs immediately, or you can store them in a cool, dry place until it's time to plant them in the fall. These bulbs go dormant in the winter, so they don't require water or attention.
- You will need to plant the offsets twice as deep as their height, but don't plant them as deep as the mature bulbs.
- Brenzel, Kathleen Norris, Ed. (2012). The New Sunset Western Garden Book, the Ultimate Gardening Guide. Oxmoor House Publishing.
- Better Homes and Gardens: New Garden Book (1990). Meredith Corporation, Des Moine, Iowa (pp 366-367).
- Nicholson, Nigel (1986). The Illustrated Garden Book. V. Sackville-West, Atheneum, New York.
- Pereire, Anita (1994). The Ward Lock Encyclopedia of Practical Gardening. Sterling Publishing Co, Inc.
© 2018 Mike and Dorothy McKenney