If you have a spacious, airy sunroom, conservatory or glazed porch, you can grow a variety of potted fruits, including figs, citrus and grapes. Apricots and peaches often crop earlier and better under cover than outdoors, although they benefit from spending the warm summer months out in the garden, as do most types of fruit trees and shrubs.
With the exception of strawberries, most fruit-producing plants are trees or shrubs that need a deep and nutritious root run, so choose containers that are at least 1 foot (30 cm) in diameter and a little more in depth. As plants grow, move them into larger pots or small tubs. You can also root prune them each year to maintain a convenient size. Alternatively, for mature plants, remove just the top layer of soil in the pot and replace this with fresh compost each spring.
In general use a soil-based compost placed over a generous layer of drainage material such as earthenware crocks, pebbles or gravel. Water and feed regularly, especially while plants are bearing flowers and fruit, when a high-potash fertilizer is recommended.
1. Peaches and nectarines: Natural or genetically dwarf varieties such as bonanza (peach) and nectarella (nectarine) can be grown as short standards on 30-inch (75 cm) stems. Keep them indoors in a well-lit, sunny position in temperatures of 50 to 55°F (10 to 13°C) until fruit sets, when they will require higher temperatures of 65 to 70°F (18 to 21°C). Ventilate freely in warm weather.
2. Apricots: Compact varieties such as Shipleys and Goldcot on semi-dwarfing St Julien A rootstocks are highly productive in pots, especially if they are trained against a sunny conservatory wall. For apricots, use a soil-less potting compost over plenty of drainage material. To ensure fruit, hand pollinate by transferring pollen from one flower to another with a paintbrush.
3. Mulberry: This slow-growing tree is ideal for a large pot. For tasty fruits that ripen in early summer, grow the black mulberry Morus nigra Chelsea in bright, indirect light in a well-ventilated spot, at 55 to 70°F (13 to 21°C).
4. Cape gooseberries: The cape gooseberry (Physalis pruinosa) and ground cherry (P. angulata) both make bushy pot plants, with small, tomato-like, white flowers and cherry-size, yellow or red fruits in papery husks. They are very prolific when grown in large pots, 1 foot (30 cm) or more across, in direct sunlight near a window.
5. Dwarf pomegranate: For pot cultivation, choose the small Punica granatum var. nana, which grows only 3 feet (90 cm) high and often produces its conspicuous scarlet flowers while relatively immature. Attractive miniature fruits follow in early autumn but seldom ripen. Plenty of ventilation and sunlight are needed, especially in late summer and autumn.
6. Figs: All varieties fruit more heavily if their roots are confined to a large pot, but Negro Largo does particularly well as a houseplant. A temperature range of 55 to 65°F (13 to 18°C) can limit the mature size of the plant, but it may still be necessary to prune in summer and winter to control exuberant growth. Set in a well-lit spot away from direct sun, and feed the plant sparingly two or three times in the growing season.
7. Grapes: A vine provides shade and looks ornamental trained up walls and across the roof of a conservatory. Ventilate freely to prevent mildew spoiling the fruit. Each winter, shorten the sideshoots back to two buds.
8. Strawberries: Alpine strawberries in pots on a sunny windowsill will fruit almost continuously from early summer until mid-autumn. Large-fruited strawberries will also do well, and are especially valuable when forced to produce early fruit. To stimulate early strawberries, pot up plants in autumn in 5- to 6-inch (13 to 15 cm) pots and leave in a well-lit room. The plants should develop edible crops from late spring onwards, after which they can be discarded or planted out in the garden to grow on.