How to grow strawberries in containers: hanging baskets, strawberry pots, and everbearing picks

June-bearing or everbearing?

Strawberries come in three types, and for a container the choice matters more than the variety name.

• June-bearing varieties produce one large crop over two to three weeks in late spring or early summer, then stop. They give the biggest single harvest, which is ideal for jam and for a garden bed. In a small space, three weeks of fruit followed by nothing is less useful.
• Everbearing varieties produce a crop in early summer and another in late summer, often with fruit in between. Newer day-neutral varieties, which are usually sold as everbearing, flower and fruit steadily from June until the first frost as long as temperatures stay between about 40°F and 85°F.
• Alpine strawberries are small, intensely flavored, and fruit all season. They tolerate part shade and suit a windowsill trough.

For most containers, a day-neutral or everbearing type is the better choice: a smaller amount of fruit, spread over the whole summer, from plants that crop the year you put them in.

Choosing a container

Each plant wants roughly 2 gallons of mix and about 8 inches of space from its neighbors. Strawberries have shallow roots, so width matters more than depth; 8 inches of depth is enough.

Hanging baskets are one of the best containers for strawberries. A 14-inch basket holds three plants, the fruit hangs clear of the mix so it stays clean and dry, slugs cannot reach it, and the basket can hang where it gets the most sun. The trade-off is watering: baskets dry fast and need daily attention in summer.

Troughs and window boxes 8 inches deep suit a row of plants along a railing or sill. Plain pots of 2 to 3 gallons hold one plant each, and a wide 5-gallon pot holds three. Fabric grow bags work well and are light.

The classic terracotta strawberry pot with pockets up the sides is a beautiful object and a hard container to grow in. The pockets hold barely a cup of mix each, dry out in an afternoon, and the lower plants never get enough water. If you want to use one, push a length of perforated pipe down the middle before filling and water through it, so the bottom pockets get a share.

Planting

Strawberries are sold as bare-root crowns in early spring or as potted plants through the season. Plant in spring once the mix is workable, or in late summer for a head start next year.

1. Fill the container with fresh potting mix and a handful of slow-release balanced fertilizer.
2. Set each plant so the crown, the point where the leaves meet the roots, sits exactly at the surface. Buried crowns rot; exposed roots dry out.
3. Water in well and put the container in full sun.
4. On day-neutral plants, pinch off the first flush of flowers for the first three or four weeks so the plant puts its energy into roots. After that, let it fruit.

Strawberries prefer slightly acidic mix, and standard potting mix is close enough. Avoid adding lime.

Sun, water and feeding

Six or more hours of sun gives sweet fruit; with less the plants grow and flower but the berries stay small and tart. Alpines are the exception and fruit in three to four hours.

Shallow roots and a fruit that is mostly water mean strawberries need consistent moisture. Check daily in summer and water until it drains. Dry spells while the fruit is swelling give small, hard berries. Water the mix rather than the plants, since wet fruit rots.

Feed every two weeks once flowering starts with a liquid tomato feed, which has the potassium that fruit needs. Too much nitrogen gives a big leafy plant and not many berries.

Protecting the fruit

Birds find red strawberries before you do. A length of netting over the container, held off the plants with a few canes, solves it. In a hanging basket the fruit is usually out of reach of slugs, but in pots on the ground a ring of copper tape or a few slug pellets in the evening protects the ripening fruit.

Keeping the fruit off the mix keeps it clean and stops it rotting where it touches. In a pot, a layer of straw under the fruit does the job; in a basket, the fruit hangs free.

Runners, and free plants

Through the summer, strawberry plants send out runners: long stems with a small plantlet at the end. Left alone, they root wherever they land and the pot becomes a tangle. Cut most of them off, which keeps the mother plant productive. Keep one or two from your best plants, pin the plantlet into a small pot of mix while it is still attached, and cut the runner once the plantlet has rooted, after three or four weeks. Those are your replacements for next year, free.

Day-neutral varieties produce fewer runners than June-bearers, and alpines none at all.

Over winter, and how long plants last

Strawberries are hardy perennials and survive winter outdoors in most climates. In a container the roots are more exposed than in the ground, so in cold regions move pots against a sheltered wall, bunch them together, and mulch the surface with straw. Baskets can come down and sit on the ground. Water occasionally through winter so the mix does not dry out completely.

Plants crop well for two to three years and then decline. The simplest routine is to pot up a few runners each summer and replace the oldest plants each spring, so the planting renews itself.

Common problems

Harvest

Pick strawberries when they are fully red all over, ideally in the morning before the sun warms them. Pinch the stem just above the fruit rather than pulling the berry. Day-neutral plants in full sun give a handful every few days from June to frost, which is more useful than it sounds. Eat them the same day; they do not keep.

Common questions