Cucumbers were mainly grown in low, narrow houses up to 4.5m in width, but many commercial growers now use VENLO multispans or the 9m wide aluminium vinery type houses.
Several F1 hybrids are now grown eg Green Spot (this being similar to BDR), Top Score and Feminex, which has 100% female. BDR is still grown and Telegraph is popular for amateur gardeners, especially in cool houses.
Propagation – Main crop
Propagation is often from mid-December onwards, however on commercial nurseries specialising in cucumbersdates often commence in late September, as follows if sowing in batches for a successional cropping programme.
Sowing dates Propagation period Harvest date commences
September – October 8 weeks February
January – February 5 weeks mid March
March – May 4 weeks 7 weeks after sowing
Two weeks can be deducted from sowings made in the period October to March by using supplementary lighting. Germination takes 40 – 48 hours at 27°C. 90mm sizeare half filled with J.I. Compost No. 1 or loamless mix and one seed is sown per pot. Later when the young plants have grown well clear of the pot rim, the pot is topped up, using J.I.P. No. 2 or loamless mix. Propagate at 20 – 22°C and after germination lower the temperature to 18°C. Plants should be staked and spaced 300mm – 600mm apart, preferably in an east/west propagating house, or in good light conditions, soil-less composts are much more often used than J.I. composts but the growing technology thereafter requires either more liquid or the use of slow release fertilisers.
The bed should not be too large, approximately 450mm wide at the base, and 400mm deep is suitable, and it should be open and well aerated. The Layer Bed, as the name suggests, consists of alternate layers of wheat straw, horse manure (well rotted) and steamed loam, each layer being approximately 100 – 150mm thick.
One or two high nitrogen feeds may be given in March-April to established plants but avoid over soft growth. Keep plants well spaced out.
375mm thick green canes are used, usually one to each main shoot. Regular tying in of shoots is essential to prevent straggly growth, some cultivars being worse than others in this respect. Where plants are potted on to 125mm, use 500mm canes.
It is usual to grow two or three different colours so that boxes of mixed colours can be marketed.
Galilee pink double flowers. Variegated– Crocodile
Mdme Crousse pink, veined maroon. Striped flowers – Bacaraat
La France lavender
Bacaraat striped flowers
Cultivars with striped petals (red and white) have become very popular. This striped effect is achieved by inoculation with a virus. The same infection on the usual geraniums does not produce such an attractive effect. Normalby maintain the stock and there are no other serious signs of deterioration from the infection.
White fly can be troublesome and regular fumigation with HCH may be needed. Resmethrin may be used. White oil emulsions are also effective.
A thickening of the under surface of the leaves called oedema, due to overwatering, is not uncommon. This condition may be made worse when plants are grown on capillary benches. (It may also come about from the use of white oil emulsions which are too thick with oil.)