How to Grow Cucumbers – Cucumis sativus
Cucumbers – Cucumis sativus
There is a distinct difference between greenhouseand varieties that are to be grown outdoors. Greenhouse varieties produce the long smooth cucumbers you see in the shops. The male flowers of traditional greenhouse varieties must be removed constantly to avoid bitter fruit, but modern all-female varieties avoid this problem.
Outdoor ridge cucumbers are shorter and pricklier, although modern varieties are less extreme. They grow well in a greenhouse, and are the best choice for unheated greenhouses in cold areas. Look out for varieties with resistance to powdery mildew.
Sow seeds in individual 9cm pots four to five weeks before planting, at about 21°C for all-female greenhouse varieties, and about 18°C for others. Sow the flat seeds on their edges to avoid water collecting on them and causing rotting. Keep the young plants warm, ideally at around 20°C.
The young plants are very sensitive to cold. Greenhouse varieties need temperatures above 15°C, which usually means planting in early summer in an unheated greenhouse. You could screen off part of the greenhouse to give the plants the extra warmth and humidity that they need. Outdoor varieties are slightly hardier Like tomatoes, cucumbers do best in a well-composted or manured border, but they can be grown in 30cm pots. They were traditionally grown in hot beds. Make sure that the borders or beds are well drained. Take care not to bury the stem when planting, and avoid watering right at its base.
All-female varieties produce cucumbers at the leaf joints on the main stem. Thus, you can remove all the side shoots on these varieties and train them like tomatoes. Other varieties are best trained on a network of strings or wires, or on large mesh netting. Here, the cucumbers are produced on side shoots, which should be pinched off one leaf beyond the developing fruit. Water the plants regularly once they are established. A thick mulch of hay or straw will help to keep the beds moist and also to create a humid atmosphere.
Harvest from late summer to mid-autumn. Pick regularly to encourage further fruiting.
Pests, diseases, and disorders
The main cucumber pests are red spider mite, aphids, and whitefly. Stem or foot rots can also be a problem, particularly with young plants. Older plants are frequently affected by powdery mildew, particularly at the end of the season if the weather is hot.