14:41 - 06 April 2011
The greenhouse is the perfect place to grow a variety of fruit. In fact some fruit such as greenhouse grapes will positively thrive in the warmer environment under glass that mimics the Mediterranean conditions they are used to.
But even less exotic fruit such as strawberries can be successfully grown under glass for an earlier crop. Simply plant them up in large pots, strawberry planters or deep growing bags and grow them on in the greenhouse. You can harvest the fruit as it ripens very easily and if you also have a strawberry patch outdoors you extend the cropping season by several weeks. Early strawberries are expensive to buy in the shops and if you grow yours organically in organic compost and without the use of pesticides and chemical fertilisers you double the value of your crop almost instantly. Once your plants have fruited you can move them out of the greenhouse to make room for other summer plants.
One of the most important considerations when growing fruit underglass is that almost all fruiting plants require pollinating. The very nature of a greenhouse can preclude access by pollinating insects and even if they can get in to collect pollen and nectar from your plants they may not be able to return to their base and convey the location of the plants that you want pollinating to their foraging friends. If you are going to leave access points for insects be sure to allow plenty of escape routes too.
A greenhouse is an ideal place to grow and raise peaches, nectarines and apricots, which like a warm environment. The glasshouse protects the early blossom from frost and also helps protect against fungal disease too, but again pollination is essential. Some greenhouse gardeners utilise a paintbrush or rabbits foot and manually pollinate the flowers by brushing pollen between the blossom, this is time consuming and not as successful as insect pollination. If your plant is growing in a tub, place it on wheels so you can move it outside the greenhouse when in flower for pollinating insects to visit the flowers. Be sure to move it back inside at night just in case a heavy frost is threatened. Peaches and apricots can also be fan trained against a wall within a lean to greenhouse or even a conservatory, but then access for insects or manual pollination is essential.
Currants, gooseberries and raspberries will not really benefit from the warm greenhouse environment and are better grown outside, again these are insect pollinated and will crop better where insects have full access to the flowers.
Other fruits that are good to grow underglass include melons. These can be grown from seed in the same way as greenhouse cucumbers and trained along the greenhouse framework. Be sure to provide adequate support for developing fruit that can become extremely heavy when ripe. You could also try growing cape gooseberries under glass or in a polytunnel. These are easy to grow from seed and very prolific, fruiting in late summer and early autumn.
Tree fruit such as apples, cherries, plums and pears are not well suited to a greenhouse environment and will crop better if grown outside and planted directly in the soil. Again they need good pollination between the plants and natural pollinators in the garden best achieve this.
Don’t forget that botanically tomatoes are fruit anyway and many large beefsteak varieties are sweet and delicious. Be a little creative and use surpluses to make tomato marmalade and sweet tomato tarts. Sprinkle brown sugar on cut cucumbers and you could believe you were eating melon; it’s a great way to use up surplus cucumbers and a delicious snack.
