Why a patio can be the best place for soft fruit

Soft fruit and small spaces get on surprisingly well. Strawberries, blueberries and currants are all woodland or hedgerow plants that cope with a restricted root run, and many of the modern compact varieties were bred with exactly this in mind. Growing them in pots also gives you advantages the open plot cannot: you choose the compost, so you can give blueberries the acid conditions they crave and strawberries the free drainage they need. You can move pots along a wall to chase the sun, whip a net over them when the blackbirds arrive, and lift them onto feet so winter wet drains away.

A south or south-west facing patio, ideally with a wall behind it, holds warmth into the evening and ripens fruit earlier and sweeter than an exposed bed. Even a modest yard will comfortably carry half a dozen pots and a couple of troughs, which is more than enough for puddings, jam and a bowl on the breakfast table through July.

Choosing compact varieties that earn their space

Variety choice matters far more in containers than in the ground, because you are asking a lot of a small volume of compost.

• Strawberries — allow three to five litres of compost per plant, so a 60cm trough takes three. 'Cambridge Favourite' is a dependable mid-season cropper, while everbearers such as 'Aromel' or 'Mara des Bois' fruit on and off from June to September. Alpine strawberries like 'Alexandria' are tiny, intensely flavoured and produce almost no runners, making them perfect for a hanging basket.
• Blueberries — these need a big pot, 30 to 40 litres for a mature bush. Compact types such as 'Top Hat', 'Northblue' and 'Sunshine Blue' stay manageable, while 'Bluecrop' is larger but heavy cropping. Plant two different varieties close together; cross-pollination gives noticeably bigger berries.
• Currants — blackcurrants 'Ben Sarek' and 'Ben Connan' are naturally compact and crop on short stems, so they suit a 30 to 40 litre pot. Redcurrant 'Laxton's No. 1' and whitecurrant 'White Versailles' are equally happy in containers and need no pollinating partner.

Compost, drainage and the ericaceous question

For strawberries and currants, a mix of peat-free multipurpose compost with a third by volume of loam-based John Innes No. 3 gives body, holds moisture and stops the pot blowing over. Blueberries are the exception: they must have ericaceous compost at roughly pH 4.5 to 5.5. If you garden on chalk or your tap water is hard, water them with rainwater from a butt whenever you can, because alkaline water gradually pushes the pH up and the leaves turn yellow between the veins.

Whatever you plant, drainage comes first. Put a layer of broken crocks or polystyrene in the base, stand pots on feet rather than flat on the slabs, and never leave them sitting in a saucer of standing water for days on end. A mulch of bark chips over the compost surface slows evaporation, and a collar of gravel around strawberries keeps the fruit off the wet and makes life harder for slugs.

Watering and feeding through the season

If one job decides whether you get a crop, it is watering. Container compost dries out fast, and strawberries in particular have shallow roots. From flowering until the last fruit is picked, aim to keep the compost evenly moist — damp, never sodden, never bone dry. In a July heatwave a fruiting pot may need water twice a day. Push a finger in to the second knuckle, or simply judge by the weight of the pot.

Irregular watering is the usual cause of split currants, leathery skins and disappointing flavour. A drip line on a timer takes the guesswork out of it, and a handful of water-retaining granules stirred through the compost helps bridge the odd missed evening.

Feeding begins as the flowers open. Switch to a high-potash tomato feed, given weekly at the strength on the bottle, and use an ericaceous feed for blueberries. Go easy on nitrogen-rich feeds, which simply build leaf at the expense of fruit. Currants in pots appreciate a top dressing of compost in early spring and a sprinkle of sulphate of potash in June.

Pruning, netting and keeping plants cropping for years

Netting is non-negotiable once fruit starts to colour. Use a fine mesh draped over a frame of canes so the birds cannot peck through to the berries, and check it regularly for trapped wildlife.

• Strawberries — cut off old foliage after cropping, and replace plants every three years using runners from your healthiest specimens, as vigour and yield fall away with age.
• Blackcurrants — fruit is borne on one-year-old wood. Each winter, cut out about a third of the oldest stems at the base to encourage fresh growth.
• Red and whitecurrants — shorten side shoots to two buds in winter and keep a open, goblet-shaped framework.
• Blueberries — prune lightly in late winter, removing twiggy and congested growth, and top-dress with fresh ericaceous compost each spring.

Watch for vine weevil, which thrives in pots; tell-tale notched leaf edges mean the grubs are in the compost, so drench with nematodes in late summer. Over winter, raise pots onto feet so they never sit in cold, wet conditions, and move terracotta somewhere sheltered to avoid frost damage. Give it a season or two and a few well-chosen pots will out-crop a whole bed of the same plants — with far less weeding and a great deal more pleasure.