Strawberries planted in late summer give a full crop next summer

The best time to plant strawberries in the UK is from early August to mid-September. Plants put in then root into warm soil before winter and crop well the next summer. If you miss that, plant from early March to mid-April instead.

Those dates are for a typical lowland garden in England and Wales, where the first frost comes around the end of October and the last around 20 April. In Scotland and the north, aim for the August end of the autumn window and the April end of the spring one. In the south-west and in sheltered city gardens you have a little more leeway at both ends.

Bare-root runners or pot-grown plants

Strawberries are sold two ways.

Bare-root runners are young plants lifted from the field and sold without soil, usually in bundles. They’re the cheapest way to fill a bed. You’ll find them for sale in late summer and autumn, and again in early spring. Plant them as soon as they arrive, since the roots dry out quickly. If you can’t plant straight away, soak the roots in water for an hour and then plant, or heel them into a spare patch of soil for a few days.

Pot-grown plants cost more but are easier. They already have a root ball, so they settle in quickly and can be planted at any time the ground isn’t frozen or waterlogged. You’ll still get the best results planting them in the same late-summer or spring windows.

You may also see cold-stored runners offered in spring and early summer. These have been kept dormant in a fridge and fruit quickly after planting, which is useful if you want a crop the same year.

Autumn or spring planting

Autumn planting gives the plants time to build a root system before winter. They start growing as soon as the soil warms in spring and give a proper crop in their first summer.

Spring-planted strawberries crop more lightly in the first year. A common approach is to pick off the first flowers so the plant puts its energy into roots and leaves, and gets a much better crop the following year. If you’d rather have a few berries straight away, leave them on: the plant will cope.

How to plant

1. Choose a sunny, sheltered spot. Strawberries need full sun to ripen sweet fruit.
2. Avoid ground where strawberries, potatoes or tomatoes grew recently, as they share soil-borne diseases such as verticillium wilt.
3. Dig in plenty of well-rotted compost or manure, because the plants will be there for several years.
4. Space plants 35 cm apart in rows 75 cm apart. In a raised bed, four plants per 30 cm square works as a closer alternative.
5. For bare-root plants, make a small mound in the bottom of the hole and spread the roots over it.
6. Set the crown (the thick, short stem where the leaves join the roots) exactly level with the soil surface.
7. Firm the soil and water well.

The crown depth matters more than anything else here. Planted too deep, the crown stays wet and rots. Too shallow, and the roots dry out and the plant struggles.

Straw and protecting the fruit

As the fruit starts to form in late spring, tuck straw under the plants. It keeps the berries clean and off wet soil, which cuts down on grey mould and slug damage. Strawberry mats or a sheet of fleece work in the same way.

Strawberries are hardy, but the flowers aren’t. A frost in April or May can kill open flowers, which show a black centre afterwards and won’t make fruit. If a frost is forecast once the plants are in flower, cover them overnight with fleece.

Birds find ripe fruit before you do. Net the plants once the berries start to colour, using a frame so the net doesn’t sit on the leaves.

Runners

In summer, strawberry plants send out long stems (runners) with baby plants on the end. If you leave them, they root everywhere and the bed turns into a mat of small, unproductive plants.

Cut most runners off as they appear. To make new plants, choose a few strong ones from healthy parents, peg each baby plant into a small pot of compost while it’s still attached, and cut the stem once it has rooted, after about four to six weeks. That timing has the young plants ready for the August to September planting window.

Replacing plants every few years

Strawberry plants crop best in their second and third years, then decline as they get older and pick up virus. Replace them after about three years. The easy way to do this is to plant a new row from runners each autumn and dig out the oldest row, so you always have plants at their best.

When you start a new bed, move it to fresh ground if you can rather than replanting the old spot.

Common problems

• Plants not growing away after planting: usually the crown is buried or the plant dried out. Check the crown is at soil level and keep new plants watered for the first few weeks.
• Small, soft or mouldy fruit: often a wet summer, crowded plants or fruit lying on soil. Thin out old plants, remove runners and use straw.
• Few berries on old plants: they’re past their best. Replace them.