Monthly Calendar May
Geraniums should not be watered too copiously; this encourages too much leaf growth which is detrimental to the plant’s bud formation. It is better to keep the Geranium indoors until the second half of May, as night frost my still occur at this time of the year. Azaleas that have been plunged in the ground outdoors should now be sprayed daily over the crown if the weather is dry. They also need feeding once a fortnight. The flowering Gloxinia (Sinningia) needs to be protected from direct sunlight and watered freely over the soil around the tuber.
To provide adequate humidity, it is advisable to place the plant on an ‘island’ in a dish of water, but make sure that the base of the pot is just above the water level. If you still have cyclamens in the living room, repot them towards the end of May and give them a cool, airy environment. Given the right conditions, they can also be placed in a well-sheltered spot in the garden.
The busy Lizzie (Impatiens) and the Solanum (Christmas or Jerusalem Cherry) can likewise be placed outdoors, providing they are given a sheltered position in the shade.
Bromelias should be screened from the warm noonday sun; soft water may now be poured into the funnel. The same applies to the Cryptanthus, a low-growing member of the bromeliad family, with a flat rosette. Since this species does not have a true funnel, it absorbs water less easily, so make sure the soil-ball does not dry out. It responds well to an occasional feed with a liquid fertilizer diluted in soft water and sprayed over the leaves.
There is still plenty of opportunity for dividing and taking cuttings, especially of cacti and succulents. However, before potting up the latter, allow the sections to dry out for at least a week. Cuttings of the Opuntia are best tied to small stick to prevent them falling over. The Calla or Arum Lily (Zantedeschia) is ready to take its natural resting period (May-July); withhold both water and fertilizer. The foliage can be allowed to dry out almost completely.
The Hydrangea that has flowered in the living room in the spring can now be placed out of doors. Cut back the foliage to about 2cms above the old wood (recognizable by its slightly darker tint) and plunge the pot into the ground in a sheltered, well-shaded spot in the garden. Gradually increase watering when new growth appears, and feed regularly.
Authors: A. C. Muller-Idzerda, Elisabeth de Lestrieux, Jonneke Krans