CARING FOR GERANIUMS

GERANIUMS, properly called pelargoniums to distinguish them from the hardy geraniums or cranesbills, are among the best of plants for summer bedding and for general greenhouse display.

All these geraniums are increased by cuttings which root easily. They will root if taken at any time of the year, but they are usually taken in August and September for flowering the following summer, in February or March for flowering in winter. Plants may be bought from April onwards but should not be planted outdoors until the end of May or early in June, after the danger of frosts is over.

Cuttings should be 3 or 4 in. long with, three or more buds between the tip of the shoot and the base of the cutting. After they have been cut from the parent plant they must be trimmed just below a pair of leaves, using a very sharp knife or razor blade to cut squarely across the stem. Rest the cutting on a hard surface such as a sheet of glass or a board while you are doing this. Then cut off the lower leaves. Have ready a supply of well-drained 2-in. Pots of John Innes Rooting Compost. Into which the cuttings are inserted singly, deeply enough to keep them upright, usually about an inch or so.

Alternatively, six or eight cuttings may be inserted round the edge of a 5-in. Pot. Use a dibber of pencil thickness to make holes for the cuttings. The ends of the cuttings may be dipped in a hormone rooting powder before insertion, although this is not essential. Keep the soil in the pots moist but not wet and keep the cuttings shaded from strong sunshine, in a minimum temperature of 60 degrees F. They benefit from a daily overhead syringing with clear water. In about a fortnight they should be sufficiently rooted for them to be moved on into 3-in. Pots. The time to do this can be judged by examining the root system by carefully knocking the cutting from its pot. If the white roots have reached the edges of the pot, it’is time to pot on into John Innes Potting Compost No. 1, with as little disturbance as possible. Do not pot too firmly and avoid over-watering particularly immediately after repotting. Instead give the rooted plants a good soaking and then refrain from watering them again until the soil is almost dry. If the cuttings are rooted in late summer or autumn they may be kept cool, in a minimum temperature of about 45 degrees F. until March. They should then be potted on into a poi one size larger and the tip of the main shoot should be nipped out. When the sideshoots reach a length of about 2 in. the tips of these too should be nipped out. This will produce a bushy plant, well-furnished with flowering shoots. Plants should not be allowed to become pot-bound but should be potted on into 5-in. Then 6-in. Pots as soon as they begin to fill the smaller pots with roots. The John Innes Potting Composts are quite suitable and No. 2 or No. 3 should be used for the final potting. However, if the plants are destined for planting outdoors the final potting into 6-in. Pots will be unnecessary. Remove any flower buds which form until about a fortnight after the final potting, in order to encourage the formation of larger numbers of flowering stems.

For flowering in winter the cuttings are rooted in February or March, and in April the plants will have developed sufficiently for the tips of the main shoots to be nipped out. By May or June the side-growths will be ready for pinching out in the same way and after that the plants may be kept out in a cold frame, growing steadily, repotting them when necessary. Early flower buds may appear but any that appear before September should be pinched out. Plants will need feeding twice a week with weak liquid plant food during the summer. They should be brought into the greenhouse in September and watered moderately from then on. They should flower for most of the winter.

After plants have finished flowering, the shoots may be cut back and the plants kept cool and watered moderately. They should be repotted before they are started into growth in their next season, when they will make large plants.

Geraniums used for bedding should be lifted in September before they are affected by frost, then potted into 3- or 4-in. Pots or into shallow boxes and stored in a cellar or cool greenhouse where the temperature does not fall below 45 degrees F. They may be started into growth again early in the following spring for later planting out.

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