GROWING AMARYLLIS IN THE HOME

By Howard Drury

Introduction

Although this popular plant is usually referred to as "Amaryllis" it is more properly called "Hippeastrum". However, in this Fact Sheet, we shall continue to use the word "Amaryllis" to denote the large flowering bulb grown each year as a houseplant. The Amaryllis originates from tropical and subtropical South America where they are to be found in wooded or savannah regions which have a period of drought each year during which time the leaves die down completely. The bulbs which we raise as houseplants come from two sources: those which blooms in autumn originate from South Africa and the spring flowers types are imported from Holland. It is a truly spectacular plant with an enormous flower spike of up to 3 ft. in height with large trumpet shaped flowers subsequently unfolding at the top. The strap like leaves usually appear after the flower bud has developed. All this magnificence can be grown on a window sill in the average house.

The best-known Hippeastrum types are those with large flowers in shades of white, pink and bright red. There are however, smaller varieties producing slightly less flamboyant flowers, which are equally beautiful. There are varieties that produce striped or frilled blooms, but with any type, the entire process for bulb to flower takes around 6-10 weeks. This plant is usually bought as a dry bulb and can be planted at any time from October until the end of April. Specially treated bulbs can be obtained to flower at Christmas and New Year, and obviously these will require potting up during the autumn. When buying dry bulbs, choose large, firm bulbs with a good system of white roots. Do not buy those with short, dried or non-existent roots.

Planting

Each bulb should be planted in a clean 12-15 cm (5 7”) pot with good drainage holes at the bottom. Use a good potting compost such as John Innes No.3 with extra grit for drainage as this bulb cannot stand being waterlogged, or mix your own using three parts of good loam, one part of well decayed manure plus a handful of silver sand and a pinch of bone meal. Take care not to damage the delicate roots of the Amaryllis when planting, and firm the compost down so that about half of the bulb is exposed. Moisten the compost, but do not over-water. Some growers believe that better results are obtained by soaking just the base and roots of dry bulbs for 24 hours in a shallow dish of water before planting, as described above.

Aftercare

Unlike Hyacinths or Tulips, Amaryllis does not require a period in the dark and the pot should be placed in daylight in a very warm spot. The tropical origins of the plant make heat of primary importance in the development of the stalk. Guard the plant against draughts and move it to a warmer spot, away from the windowsill at night when necessary. A temperature of 21c (70f) is ideal.

Watering

Watering should be sparse at first, using only enough to keep the compost moist. Once the flower stalk begins to appear, the watering can be stepped up. Allow the surface of the compost to dry out between thorough soakings using tepid water. The stalk will then grow with tremendous speed and when it slows the flower petals will unfold. During the flowering period, a temperature of around 18c (65f) will suit the plant; too much heat will considerably shorten the flowering stage in the life of your Amaryllis, which should last for many years.

Growing in subsequent years

It is possible to keep the bulb from year to year. After flowering has finished, remove the old flower tubes at the top of the flower stalk, but do not cut the stalk down. Apply a standard liquid fertilizer (preferably with a high potash content) at weekly intervals whilst the leaves continue to develop to full and continue feeding until late September. It is important to keep the plant in the same warm temperature and ensure it receives plenty of light. As the leaves begin to die back, (often around late September or October) stop feeding and reduce watering by giving less each time and increasing the interval between watering. Allow the leaves to die down naturally and when the bulb enters its dormant period, cease watering completely. Remove all dried, dead foliage and place the pot in a cool, dry place for a period of at least two months. This period, which will normally occur between October and December, is essential for the life cycle of the bulb. If the leaves do not start to die back naturally, you MUST reduce and finally stop watering to encourage a period of dormancy. The bulb should be left in the pot which must be stored in a cool light and airy place for a minimum of eight weeks Critically the bulb needs temperatures of below 10c (50F) to promote formation of the new flower bud and stalk, it is the rapid warming following the cool winter rest that induces a long flower stalk prior to the leaves emerging. Failure to complete this drying off and cool rest will mean that the bulb will not flower during the following season.

It is as well to remember that autumn sold bulbs are normally specially treated to bloom early, and will need very careful and precise care to ensure flowering the following year, and this is often the reason for a disappointing performance in subsequent seasons. A useful pointer is to note carefully whether the flowers stalk or the leaves are the first to emerge. If the bulb produces a mass of foliage before any signs of the flower spike, then it is unlikely to produce blooms that year. Autumn flowering bulbs, which have been forced often, require one year's rest (producing leaves, but no flowers) before they will bloom again. When the bulb shows signs of producing new growth, usually in spring, begin watering again and bring the plant back onto a window sill to repeat the flowering cycle. It is possible, in future years, for the bulbs to increase in size and even produce additional flower stems.

Repotting

It is not necessary to repot every season, but it can be helpful as it enables all old soil and dried roots to be removed and is a protection against disease. Any repotting or addition of fresh compost should be carried out just at the beginning of the growth period. For the first three or four years after the initial potting, it is usually sufficient to lift the bulb and root ball from the pot, remove a little loose mixture from between the roots and above, replace the bulb in the pot and work some fresh compost into the spaces made. Repotting completely should only be necessary every three to four years.

Propagation

It is possible to raise further Amaryllis from the small bulbs that are produced around the base of the parent plant. When these are about 25-37 mm (1-1½”) across, detach them from the main bulb, with as much root as possible. Plant them in 3in  pots and treat in the same way as mature bulbs, potting on into slightly larger containers each year until they reach flowering size of about 85 mm (3½”) Do not forget to allow the young bulbs to enter a resting period each year.

Amaryllis raised from seed may take from three to five years before flowering. Sow the seeds in March in pots or boxes at 1in intervals. Cover lightly with compost and keep shaded in a temperature of 16-18c (61 to 64f) until germinated. Keep the seedlings warm and well watered until, large enough to prick out singly into 5 cm (2”) pots. The seedlings are not given a rest period, but are kept growing until they reach flowering size. This is obviously a much more laborious process than raising plants from offsets, but seedlings can produce some surprises in colour and markings.

Recommended hybrid varieties

American Express deep scarlet crimson

Appleblossom - delicate pink with white with a greenish throat

Bouquet salmon pink, eyed and veined with scarlet

Candy Cane white, streaked with crimson

Nivalis white with a yellow flushed throat

Prima Donna crimson flushed with white in bud

Dutch Belle pink blooms

Orange Sovereign warm orange blooms

Papillo - "Butterfly Amaryllis" not so widely available but very delicate red and cream blooms. Needs slightly warmer conditions that other Hippeastrums.

Picotee - white with a fine red edge also available Double Picotee

Yellow Pioneer - the first yellow variety to be offered for sale.

Suppliers

Most garden centres and florists sell Amaryllis bulbs, often in packs containing, pot and growing medium. Better Garden centres sell individual bulbs loose, allowing customers to choose their bulbs and grow them in their own choice of pot and compost. Taylor's Bulbs sometimes offer very large bulbs to garden centres at a higher price, but these can often produce three flower stems with more individual trumpets than cheaper, smaller bulbs. However, a wider selection of named varieties can be obtained from the many bulb catalogues by mail order. It is worth studying the on-line catalogues to obtain the more unusual varieties.

The information given in this Fact Sheet is provided in good faith. It is however of necessity general information and advice on the topic. Howard Drury will not be under any liability in respect of the provision of such advice and information, and you are strongly advised to seek independent advice on any particular gardening problems or queries you may have, preferably from experts who can (when appropriate) inspect the problem before providing advice.

© 2022. This material has been produced by Howard Drury and must not be reproduced in part or full without the written consent of Howard Drury, Kings Heath, Birmingham, B13 0SJ.

JHD/29/03/2022