Growing amaryllis (Hippeastrum) at home: The basics
WHAT’S IN A NAME?
The common name amaryllis is often applied to the hybrids of, but less often to the 90 or so species of Hippeastrum. Originally, several genera (and a great many species) from both the Old and New World were classified under the Latin name Amaryllis. In the 19th century, botanist William Herbert proposed the creation of several new genera to classify and distinguish those differing from the South African Amaryllis belladonna, which he accepted as the type species. His publications were contested by botanists offering evidence that the first described Amaryllis was what we now call Hippeastrum puniceum. This led to a long period of nomenclatural confusion. The dissension among botanists was formally ended at the 1987 meeting of the 14th International Botanical Congress in Berlin, with the South African species being conserved as the generic Amaryllis, which currently consists of only two species, Amaryllis belladonna and A. paradisicola. Typically these are cultivated outdoors in Mediterranean climates under common names such as “naked ladies,” “Belladonna lily,” or “March lily.” Since popular cultivation of Hippeastrum species and hybrids began long before the nomenclature was settled; the common name amaryllis has remained with them. Today they are popular as forced bulbs for the winter holidays, especially for Christmas in the Northern Hemisphere.
I JUST GOT AN AMARYLLIS BULB, NOW WHAT?
Amaryllis bulbs are often given as holiday gifts during the winter months, either bare-root or in kits including pots and soil media. These bulbs have typically been produced in the Netherlands, Israel, South Africa, Peru, or Brazil and prepared in such a way that they will produce flowers within weeks of being received. While many people dispose of the plants after the show is over, it is quite possible to regrow the plant for bloom in subsequent years.
Upon receipt of a bulb, it is best to pot it up immediately; however it may be stored for several weeks at cool (50-60°F/10-16°C) temperatures if kept dry. The more live, fleshy roots attached to the bulb the better; they will enable the plant to take water from the soil, not just from the bulb itself. Dry, dead roots should be removed since they will decompose anyway. It is essential to provide your amaryllis with a pot and soil that ensures good drainage. If a gift box kit includes a pot without drainage, put drain holes in it, or use another pot. Many of the commercially prepared houseplant potting soils will suffice; if they are very high in organic matter or contain moisture regulating compounds add 1/3 or so sharp sand, perlite,vermiculite, etc. by volume, particularly if choosing a plastic pot. A clay pot offers more counterweight for the top-heavy plants and permits more air exchange to the roots, and is better for those who tend to over water. Plastic is less expensive, easier to sanitize and will work better for those who under water more often. Choose a pot about 2-3”/5-7.5 cm larger in diameter than the bulb itself. Partly fill the pot with soil and place the bulb in the pot. Adjust the bulb height as you fill and gently firm the media around the bulb so that the soil line is about ¾”/2 cm below the pot rim and the top 1/3 or so of the bulb is above the soil line. The practice of keeping the “neck” of the bulb well above the soil line prevents diseases associated with moisture at the growing point. In nature, some terrestrial species grow with bulbs being completely underground, while the epiphytic and semi-epiphytic species grow with most of their bulbs exposed. The hybrids are generally pretty flexible.
BRING ON THE FLOWERS!
Now that your bulb is potted, give it a drink of water to settle the soil around the bulb. Place the pot in a warm location (ideally 68-78°F/20-26°C) and keep on the dry side. Cool temperatures and excess moisture not only discourages root initiation, but can lead to rotting of the bulb and roots. Be patient! While some bulbs may already be sprouting upon purchase, others may take several weeks to commence growth. Whether bloom scapes or leaves emerge first, increase watering commensurate with growth, keeping the plant just moist through the flowering period. Bright light (including direct sun) and frequent turning of the pot will insure sturdy, straight scapes, otherwise staking may be required. Once flowering begins, the plant may be moved to a cooler location to help flowers last longer. Remove individual flowers after they fade, and cut the bloom scape to the neck of the bulb when the last flower is done. Depending on bulb size and variety you may get two or more scapes, either simultaneously or over several weeks’ time. Hippeastrum make excellent cut flowers, and often last even longer than on the plant itself. Fresh flowers broken off of the scape often keep for days with no water!
CAN I GET IT TO BLOOM AGAIN?
When flowering has ceased and foliage is being produced it is time to build the strength of the plant for next year’s bloom. Regular watering is now coupled with fertilizing. Follow label directions on a fertilizer made for flowering houseplants, bearing in mind that over-feeding a plant without adequate sunlight can produce large, but weak leaves, and may damage the roots. For sturdier growth, the plants should be moved outdoors when cold weather has passed. Choose a spot in full sun or afternoon shade, depending on your climate. In hot summer climates, try to buffer the roots from excessive heat and drying. This can be done by partly plunging pots into the garden, or “sleeving” the pot into a larger outer pot. You will be rewarded with a handsome plant bearing a fan of large strap-shaped leaves. Pest insects (aphids can vector viruses), slugs, etc. may need to be controlled, the downside of growing them outdoors.
Programming for Rebloom
Since most Hippeastrum are actually spring bloomers by nature, you probably won’t see flowers as early as December unless you force the dormancy process quite early. Allowing a longer growing season may yield a bigger, healthier bulb, so take that into consideration. Several weeks before expected frost, withhold water and fertilizer (placing the pot on its side is a common practice). The leaves will slowly yellow and begin drying off, sending carbohydrates to the bulb. Some specimens are slower to cooperate than others. Before freezing temperatures arrive, bring the plant indoors and remove the remaining foliage (even if green), trimming it to the neck with a sharp knife or shears. If working with more than one amaryllis bulb at a time, thoroughly sanitize the cutting blade between each to prevent the potential spread of viruses and other pathogens. This is the most convenient time to repot if necessary. Storing the bulb in a cool location (50-62°F/10-16°C) will induce a dormant state that allows flower scapes deep in the bulb to begin to develop, while foliage growth is suppressed. In the trade this is called “programming.” After 2-3 months you may notice a bloom scape emerging from the bulb, but even if you don’t, give it an initial watering. Once the emergence of a flower scape or foliage is noticed, move to a warm and bright location as before and prepare to have your winter doldrums brightened by the spectacular blooms of your own amaryllis!
*These guidelines represent a basic set of concepts based on growing in a temperate climate in the Northern Hemisphere, YMMV! Hybrid amaryllis bulbs are actually pretty resilient and many people succeed with them using varied techniques. Species cultivation often requires more skill in determining watering regimens, temperature preferences, specific soil and dormancy requirements and so on. Proceed at your own risk…of a new addiction!