AI Pertuit Horticulture Department, Clemson University

Anyone who knows me , the retail value of one scape being roughly knows what my favorite equal to that of a large ! is the amaryllis. Growing up in Baton In the U.S., the name "amaryllis" generically refers to Rouge, my adjacent commercially important , even though the bulbs neighbor bought new marketed in the trade are derived mainly from Dutch hybrids annually, of the Hippeastrum. (meaning: "horse star" in hybridized them, and had Greek), now the accepted genus of the hybrids that we hundreds in his yard. I grow commercially. Some, however, still use the remember the year my genus name Amaryllis for the Dutch hybrids. "Ama younger brother and his ryllis" is the common name, Hippeastrum the botanical friends, playing swashbucklers, decapitated the scapes name. Amaryllis is the generic name for A. Bella before they had a chance to open. Talk about "hell donna; but, crinium is no longer A. bulbisperma, it's breaking loose!" Crinium bulbispermum; is no longer A. radiata, it's , etc. The Hippeastrum At LSU, the pomology professor for whom I worked species name is listed in England as hybrida, but here as an undergraduate (Gary Couvillon's major profes it's vittatum.. Many people simply give the sor at the time), was really a floriculturist. Amaryllis name (e.g., Hippeastrum 'Bouquet'). occupied about a third of his "" greenhouse. His enthusiasm for amaryllis further In the lower South, it is common to stimulated my interest. He was a see outside large clumps of amaryllis great teacher in and out of the bulbs, their flowers trumpet shaped, classroom. Years later, he followed looking much in shape like an Easter his heart and switched (officially) to lily flower. Their color is red with a floriculture. white stripe or white with a red stripe. These are the "Mead strains," Except for when I was in the Army, developed in Florida by Dr.Theodore I've always managed to carry a few Mead. Their parentage includes amaryllis bulbs along with me. I bulbs imported from England and the have a couple of hundred in my yard continent by Dr. Henry Nehrling. some but mostly crosses Outside, these bulbs often grow in I've made. large clumps which add a lot of color /••'•, ' to the landscape. Although the Mead So, I've found it exciting to see the v:.i.., • types come true from , they are popularity of the amaryllis increase not as striking as the Dutch hybrids: over the past decade. I remember Fig. 1. Hippeastrum capsules their color range is very limited,and when American Express first began with seed - ready for their flower form is considered offering them for Christmas. Now, sowing inferior to the Dutch hybrids. The amaryllis are even becoming petal/sepals of the Dutch hybrids are popular for Mother's Day and far wider and more refiexed than the Easter. In fact, they're so common now that one Mead types, making their flower wider in diameter and simply has to go to the produce section of his local flatter than the Mead types. super market to purchase one. One SC greenhouse operation uses the amaryllis for its logo. The Dutch hybrids come in many colors and various combinations and tints and shades of them: white, red, Although they're not cheap, in our area they will pink, orange, and, just recently, yellow. Some of the performwell outside (even producing offshoots) year rose pinks exhibit a blue tint in their petals. A yellow after year, unlike the undependable tulip. Undevel species (H. Evansiae) was discovered in Bolivia about oped scapes occasionally are sold wholesale as cut 35 years ago. It is a relatively small bulb (ca. 11/2 inch

Page 42, Georgia Floriculture 35 years ago. It is a relatively small bulb (ca. 11/2 inch recommended! They grow like weeds! in diameter, maximum) with flower of only an inch in diameter. It's taken quite a while to incorporate the The bulblets will probably need transplanting at the 3- yellow into the larger flowering yellows available 5 month stage, again at 10 months, when you can commercially. introduce each bulb to its own pot. When transplant ing, use a mixture (by vol.) of three The flowers are produced (2-6) in parts builder's sand, four parts pine an arrangement [i.e., stems bark (soil conditioning grade), and (pedicels) of florets attached at two parts peat moss. The pH same point on main axis (pe should be adjusted with dolomitic duncle)] on the scape (i.e., a limestone to ca. 6.5. NEVER leafless, hollow stalk that originates fertilize an amaryllis bulb that has at ground level). The scape's no . Amaryllis will flower rapidity of development is truly from seed in 3 years, occasionally amazing... from being just visible at in two years... if greenhouse grown! the bulb's nose to as much as 3 feet long in a few weeks! Indi Amaryllis should be potted with ca. vidual flowers of 11 inches in one-third to one-half of the bulb diameter may open. In some above the growing medium surface. cultivars, the leaves emerge from They do well when potted this way, the bulb with the scape, but in and it keeps the bulb's nose dry, others, emergence from the precluding conditions conducive to bulb follows flowering. Often, "red blotch" infection. Potted bulbs more than one scape, usually 2, will Fig. 2. Scapes within Hippeastrum bulb thrive under conditions in which that has been cut in hull" in they are pot bound. When potting develop and flower simultaneously. mid winter. Regardless, another scape usually a mature bulb, leave only an inch develops 2 to 3 weeks after the first floral display. between the outside of the bulb and the inside of the Each flower may develop into a fruit () which pot rim. In outside beds, the bulb should be planted may contain over 100 . Seeds are a good place to with only half of the bulb's nose above ground. Heavy begin discussing amaryllis culture. mulching in the fall/winter is advised.

The capsule, after turning yellowish, will begin to split The life cycle of the amaryllis is extremely interesting. about 6 weeks after the flower opens, revealing its Seedlings do go through a juvenile stage, noted by the black seeds (Fig. 1). At this stage, the highest percent fact that they continue to grow relatively vigorously in germination will be attained... the the greenhouse in winter. The longer one keeps the seeds after juvenile stage probably ends with this point, the fewer will germinate. the initiation of the first scape Seeds not planted right away within the bulb. In winter in the should be kept in the refrigerator greenhouse, mature amaryllis have until sowing. Seeds removed from a "tendency" to have a rest period the capsule may be floated over [i.e., a period in which visible night in a bowl of water before growth completely ceases because sowing. They may be sown thickly of internal (physiological) condi (i.e., seeds touching one another) tions within the )]. Their about a quarter of an inch deep in growth slows greatly in winter, but builder's sand. In less than two it does not cease completely. In weeks, the surface of the sand will the greenhouse, if left alone, be covered with small leaf blades. mature bulbs generally flower in Continue to water them. The sand the spring, but many also flower insures good drainage, so they sporadically at other times of the won't rot. A tiny bulblet is evident year. with the formation of the second or Fig.3. Hippeastrum flower exhibiting ripe anthers third leaf. After a month, a The mature amaryllis bulb initiates complete liquid fertilizer of about 200 ppm N is flowers while growing vegetatively. Initiation of a recommended, which may be increased to 500 ppm N flowering scape within the bulb is not photoperiodi- at 4 months. After 6 months, 700 to 800 ppm N is cally controlled. Research has shown, however, that

Georgia Floriculture, Page 43 very warm temperatures (e.g., >83°Fdays, >73°F certain that no water gets into the pots. The leaves nights) increase leaf growth but reduce bulb growth should not be cut off. They should be allowed to die and the number of scapes initiated. These conditions naturally. In December, the scapes will appear at the are common in summer in the deep South. In nose of the bulb. To force them at that time, the pots general, a bulb will initiate a flowering scape following are turned uprightly and the bulbs watered. Bulbs will the production of 3 to 4 flower in 4 to 6 weeks in a leaves. It follows, then, that 62 to 65°F minimum the more leaves it produces, greenhouse. They should the more scapes it initiates. A not be fertilized until their mature bulb will average leaves begin vigorous about 12 leaves during a expansion. For later growing season, producing flowering, they can be stored about 3, and on rare occasions at40-45°F. This 40-45°F 4, scapes. If outside, growth exposure is not a necessary ceases in the fall as tempera part of the plant's life cycle tures decline, and the leaves (i.e., it does not fulfill some die back. The winter is really rest requirement because it a dormant period (i.e., it doesn't have a rest require ceases growth because the ment). This temperature temperatures are unfavor range merely acts as an able). This forced period of unfavorable environment for inactive growth induces scape Fig. 4. Hippeastrum bulbs vegetative growth and scape cut longitudinally 1/8,1/16 development (i.e., expand, and 1/32. All piece contain n development. It is simply a take up water, etc.), and by portion of the basal plate. holding temperature, and early spring the scape(s) will bulbs can be held for at be visible at the nose of the bulb, usually developing least a year at this temperature before forcing. About before the leaves, which do not appear until the 4 to 6 weeks before flowering is desired, the bulbs temperature warms up more. The winter period of should be removed from the 40-45°F storage and inactivity "programs" the scapes to develop in the watered. If they're potted during the 40-45°F storage, spring. In the greenhouse, these the bulbs must be watered same scapes might flower in late occasionally. Bulbs already winter or not develop until rooted when removed from summer. storage will force faster and produce larger flowers than bulbs The interesting part of their life which must root during scape cycle is that the scapes that development. It is possible, develop in the spring (i.e., therefore, to force amaryllis at emerge through the neck of the any time of the year. bulb, elongate, and flower) are the ones that were initiated Amaryllis are extremely easy to about 18 months previous, not pollinate. Once the pollen is on the ones initiated the just- the stigma (Fig. 3 ), the flower previous growing season! In will begin to streak and wilt other words, when it finishes within a day or so. Most of the flowering in the spring, the Fig. 5. Hippeastrum leaf blades infected seedlings produced will have scapes initiated the last growing with mosaic virus. Healthy- striped flowers, even if both season are still within the bulb left, Infected-right. parents have solid colored and won't develop until the next flowers. Also, many of the spring. At the end of the growingseason in the rail, seedlings will not have the open, flat form of their the bulb has within it scapes of two ages... those "parents" they'll be moretrumpet shaped. It is pos initiated last year and those initiated the current year sible, however, to get seedlings equal to and occasion (Fig. 2). ally better than their parent(s). In a yard, what matters iscolor (i.e., the mass effect), notthe quality In the greenhouse, one can program flowering. This is of an individual flower. accomplished bywithholding water from the plants in August and turning the pots on their sides to make

Page 44, Georgia Floriculture Amaryllis do produce offshoots, some cultivars more seeds. So, if the plant produces a nice flower, one readily than others. Any offshoot,of course, would be might make a few crosses with it before discarding it. identical to its parent. Because propagators want to sell as many bulbs as possible, they prefer that culti "Red blotch" is caused by the fungus Stagonospora vars not produce offshoots readily, and this is a curtisii (Fig. 5 ). It is very destructive and, if un consideration in whether a cultivar is released com checked, progresses rapidly within a bulb and from mercially. Offshoots initiate their first scape at ca. the bulb to bulb. This same disease is called "scorch" on 9-leaf stage, but often this first scape aborts. daffodils. The disease manifests itself by reddish brown spots that develop into lesions Amaryllis may also be propagated by on the bulb, leaves, and/or scape. The cuttings (i.e., bulb dissection). Only fungus can progress into the heart of large bulbs should be used in asexual the bulb. The scape may rot off at the propagation. First, the bulb is cut attacked location before its flowers longitudinally (top to bottom) open. Even today, it is unfortunately through its basal plate. After common for bulbs to be infected with dividing a bulb in half, the halves are both mosaic and red blotch when they halved again (total: 4 pieces), then are purchased. again... 8, and then 16. It is possible to continue to 32 (Fig. 4 ), etc., but it Captan and Bordeaux mixture used to is recommended that nonprofession be recommended for red blotch, but als stop with 16 divisions. Each cut neither is very effective. Then Benlate piece must contain a piece of the came along. It was extremely effective basal plate (stem tissue) or it will not in eradicating Stagonospora from root because new roots develop from amaryllis. If properly timed, one spray stem, not leaf, tissue. The bottom in early fall could eliminate the disease third of the cutting, which includes from a moderately infected plant. the basal plate, is buried in sand and Fig. 6. Scapes of Hippeastrum infected Because the fungicide is systemic, the watered. In several weeks, a new leaf at bulb nose with red blotch. plant probably draws the fungicide into (Stagnospora curtisii) will appear, then two, etc., then a new the bulb when it translocates its leaf bulb will form at the base. This bulb carbohydrates into its bulb as its leaves will flower in ca. two years. Asexual propagation like wither and die. It is a good idea to assume that newly this is how named cultivars are increased. purchased bulbs have the disease: soak them in a Benlate-like fungicide for a half an hour before The main pest problems of amaryllis are mosaic virus planting. Cleary's 3336 and Sierra's Domain may and "red blotch". Occasionally, plants in the green substitute for Benlate. house will get soft brown scale, but this is easily controlled. Spider mite infestation is rare, but it too is Selected Cultivars easily controlled. There are many amaryllis cultivars available. Some of There is simply nothing one can do to eliminate the older cultivars produce offshoots more readily than mosaic from a plant. Its symptom is light yellow some of the more recently released ones. streaking of the foliage. Often, new leaves do not manifest the symptom until they have elongated and 'Apple Blossom': a white flushed pink; the American matured. Initially, a plant with mosaic may perform favorite; an older cultivarwith strong substance and well, but it will have reduced vegetative growth as the ideal flower form. years progress. Eventually, it will not flower. Also, it serves as a source of infection of healthy plants. The 'Bouquet': an salmon orange with strong substance; mosaic virus can be spread by insects, also by cutting flower form is a bit triangular, caused by its petals an infected plant with a knife, then cutting a healthy reflexing too much; its color is its best attribute. one with the same knife. There is some evidence that smoking tobacco in a greenhouse can produce mosaic 'Fantasy': looks very much like 'Apple Blossom' but infection. Some believe that the virus can be transmit with a lot more and deeper color; doesn't have the ted from root to root in a bed situation. Plants substance of 'Apple Blossom'. infected with mosaic do not transmit disease to their

Georgia Floriculture, Page 45 'White Giant': aptly named; one of the largest flowers 'Red Lion': medium, clear red with verygood sub but also with one of the longest scapes; a vigorous stance grower. 'Yellow Pioneer': newcolor withonlyaverageflower 'Marie Goretti': a white with frilled edges; flowers form. have good substance and form but not many flowers per scape. Amaryllis References:

'Doris Lillian': a deep rose pink... a favorite; good Bailey, L.H. 1928. Hippeastrum. The Standard substance and flower form; open flowers have a blue Cyclopediaof Horticulture, vol. II. The Macmillan tint in their petals; can be hard to find. Co., New York.

'Wyndham Hayward': a dark red of extremelygood Bailey, LibertyHyde and Ethel Zoe Bailey, and Staff substance and flower form; this clear red color hard to ofThe Liberty Hyde BaileyHortorium. Hippeastrum. find. 1976. HortusIII. Macmillan Publishing Co., Inc., New York. 'Majuba': a scarlet with exceptionalflowerform (very wide petals/sepals which do not reflex) but tall. DeHertogh, August. 1992. Bulbous and tuberous plants. Introduction to Floriculture, 2nd Edition. Roy 'Trixie': a cherry red; very good substance and flower A. Larson(ed.). AcademicPress, Inc.,San Diego. form; color is unique. Rees, A.R. 1985. Hippeastrum in CRC Handbook of 'Picotee Petticoat': white with red lined petals/sepals; Flowering, vol. I. Abraham H. Halevy(ed.) CRC substance and form are an improvement over 'Picotee' Press, Inc. Boca Raton, Florida. but they are still only a little better than average. Post, Kenneth. 1959.Florist Crop Production and Marketing. Orange Judd Publishing Co., Inc., New York.

Laurie, Alex, D.C.Kiplinger, and Kennard S. Nelson. 1958. Commercial Flower Forcing, 6th Edition. McGraw-Hill Book Co., Inc., New York.

Pertuit, AJ., Jr. 1991. Personal notes (unpublished). Horticulture Department, Clemson University, Clemson, South Carolina.

Pertuit, AJ., Jr. 1995. Understanding andProducing Amaryllis. Hort. Leaflet63. Cooperative Extension Service, Clemson University, Clemson,South Carolina. YOUR SUPPLIER OF: Bulbs Plugs Seeds Plants CONDOR Computing, Inc. Supplies The Nurseryman's Friend StuartWhatley P.O. Box 510 UUCoUinwood Cir. Your Opelika, Al 36801 Nursery Inventory Specialists (205) 745-5092 • NURSERIES • BROKERS • GREENHOUSES Fax: (205) 745-0117 Specializing in Softwarefor GrowersSince 1982 P.O. BOX 17267 (205) 852-4490 Huntsviile, AL 35801 (205) 837-8714 FAX

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