Hippeastrums

5. Hippeastrums

About Hippeastrums

Hippeastrums, also known as Amaryllis, are native to tropical areas of South America, and enjoy growing in a constant temperature of 20ºC. This makes them ideal houseplants and they are considered to be one of the most elegant and spectacular bulbs for indoor flowering.

Planting – When and How

Hippeastrum bulbs are generally available in garden centres from the beginning of October. If planted at that time they will flower about seven weeks later at the end of November. The longer you delay planting, the quicker the bulb will rush into bloom - bulbs planted in late November will flower in three weeks and look magnificent at Christmas. It is not recommended to delay planting beyond mid December.

When purchased, the bulbs will have thick fleshy roots, and these should be handled carefully to avoid damage. Plant the bulbs in a pot at least 150mm diameter. Use a good quality potting mixture that contains a six-month slow release fertiliser. Plant the bulb with the top third above the mixture, making sure that the roots are well spread out and have no air pockets where the mixture is missing. After planting, water well with tepid water. Do not water over the nose of the bulb.

Care while growing

While the bulb is growing, use tepid water sparingly to keep the mixture just moist, not wet. Do not allow water to sit in the tray underneath the pot. If you have used a good mixture with slow release fertiliser then no additional fertilising is required.

Keep the pot in a warm room, in full light. Rotate the pot occasionally as the leaves and flower stem start to appear to prevent them bending towards the light.

Flowering

Depending on when you planted the bulb, the flower will be in full bloom three to seven weeks after planting.

At this time, remove the pot from direct sun to extend the life of the flower. Continue to water sufficiently to keep the mixture just moist.

Care after flowering

When the flower is spent, remove the flower stem as close as possible to its base. Some liquid fertiliser can be given in the water now, as the bulb needs to be well fed for the next few months to be able to flower well next season.

Keep watering the bulb for the next two to three months, the thick green leaves make it an attractive plant to have in the house even after flowering.

Secrets for successful re-flowering

Flowering in Hippeastrum bulbs is initiated by a stress period of cool conditions or dry conditions. This is why bulbs purchased in garden centres always flower well in their first season; they have been stored dry for some weeks prior to being available for sale. The stress period must be at least ten weeks to be effective.

These conditions can be provided by withholding water from the plant from the beginning of April to the end of June. By this time the plant may have lost some older leaves, but this is not a problem. Re-pot the bulb into fresh mixture at the start of July and follow the growing instructions above.

Alternatively, place the potted bulb outdoors for the winter months, in a position protected from frosts. It will probably lose most of its leaves in the colder months as it becomes dormant. Re-pot it and bring it indoors at the start of July as with the previous method.

Both methods will give flowers during late August. With careful planning, the plant can then be left to grow for another month or two and the process repeated to obtain two flowering periods each year.

Reproduced with the kind permission of Aorangi Bulb Nurseries Ltd.