Growing Annual Peppers
Of the several species of Capsicum grown for their fruits, C. annuum is the most likely to succeed in Britain. It has a relatively dwarf and branched habit—reaching a height of 0.5 to 1m (18in to 3ft)—and the fruits develop from white flowers in the leaf axils. This species contains the large fruited peppers which vary in length from 5 to 25cm (2 to 10in), and in shape from round and ‘blocky’ to long and thin. The flavour of the fruits also varies. In many of the larger fruited types it is very mild and they are frequently termed ‘sweet peppers’ although the terms ‘bell pepper’ and ‘bull-nose pepper’ may also be used. As more people travel around Mediterranean Europe so peppers have become more popular in recent years. Although plants may be grown outdoors in southern and western districts, peppers are best grown in heated or cold greenhouses or polythene structures.
Capsicum fruits are green initially and may be picked in that condition for use in salads or as a cooked vegetable. If left on the plant the fruits will eventually turn red. They can be frozen but most pepper dishes are best if fresh fruits are used.
Soil and fertilizer requirements
Peppers have similarand fertilizer requirements to tomatoes. They tend to grow more slowly in the early stages and care must be taken to ensure that the plants do not become ‘hard’. They respond to the incorporation of large amounts of well-rotted organic manure into the soil and should never be planted into ‘cold’ land. Growing peppers in containers such as 25-cm (10-in) pots has the big advantage that the soil will warm up quickly and the whole plant can be moved outside if conditions become suitable. Soil-borne which attack tomatoes may also cause problems on peppers.
This crop has a greater demand for nitrogenous fertilizers than tomatoes and, although liquid feeding is still the most convenient method, medium and high-nitrogen feeds should be used.
Pre-Christmas sowings of peppers, unlike tomatoes, are not made. The usual time to sow is February, or even March for later crops. Plant raising techniques and temperatures are similar to those used for tomatoes but you will find it takes longer to grow peppers to the planting stage. It is unlikely that plants will be ready for planting until late April or May.
Peppers may, like tomatoes, be grown in a number of ways but they are usually planted either in the greenhouse soil or in individual containers. The plants have a bushy habit and should be given more space than tomatoes. Space the plants/containers 60cm (2ft) apart in each direction. It is important to plant before the peppers become root-bound in the propagation pots. Do not plant outside until early June and then only on very sheltered sites.
The optimum conditions for growing peppers are high temperatures along with adequate supplies of nitrogenous fertilizer and water. Minimum temperatures of 18°C/64°F should ensure uninterrupted growth. Because of their branched, bushy habit peppers need supporting to give all the shoots a chance to develop. When the plants are about 30cm (12in) tall they will terminate in a flower which may either be allowed to develop into a fruit or pinched out. If they are retained then a flush of early peppers will result but there will then be a delay before the next fruits are ready. Removal of the terminal flowers will cause a later, but more continuous, fruiting pattern. If three or four shoots on each plant can be separately supported with canes or strings then light and air will be able to penetrate and fruit development will be better.
Pepper fruits are most commonly picked green but waiting another 3 weeks will allow them to turn red. Regular picking is essential to ensure that subsequent fruits continue to grow. The secret with most fruiting vegetables is to regulate plant growth so that vegetative development and fruit production can go on at the same time. If plants are carrying too much fruit at a particular time then vegetative growth— and future fruiting—will slow down. Remove the fruits with a sharp knife.
Pests and diseases
Peppers are subject to most tomato disorders but the most important are glasshouse red spider mite, glasshouse whitefly, tobacco mosaic virus and blossom end rot. Aphids (greenfly) are likely to be a much greater problem on peppers and care must be taken to eradicate them at an early stage.
‘New Ace’: F1 hybrid: early and high yielding; best under protection. ‘Canape’: F1 hybrid; early but may also be grown outdoors. ‘Outdoor’: suitable for outdoor culture under cloches; yellow fruits.
Soil and fertilizer requirements
Aubergines have very similar requirements to tomatoes and peppers. Like the latter they may either be grown in the greenhouse soil or in individual containers. If they are planted outdoors a very sunny, sheltered site must be used.
Seed sowing, planting and crop management
Sow seed during February in the same way as for tomatoes and germinate at a temperature of 21°C/70°F. When they are large enough to handle, prick theout into individual 10-cm (3-½-in) pots and grow them on in the same way as tomato plants. They will be ready for planting in May when they should be spaced 60cm (2ft) apart in each direction. Lateral branches will be encouraged if the growing plant is pinched out when the plants are 15cm (6in) tall. Aubergines prefer high temperatures and humidity so be prepared to spray the plants regularly with water. Use the same feeding regime as for peppers and stake the plants in order to allow 3 or 4 shoots to develop on each.
In good growing seasons it may be necessary to limit each plant to 4 to 6 fruits only. From a May planting in heated greenhouses it should be possible to pick fruits in mid-July. Space outdoor aubergines 60cm (2ft) apart in each direction. Plants can be grown under protection in containers in early summer and then moved outside on to pathways or patios when the weather is warm enough.
Cut off the fruits with a sharp knife.
Pests and diseases
The major pests are aphids—which can have devastating effects if not controlled— glasshouse whitefly and glasshouse red spider mite.