Propagating Strawberries from Runners

Strawberry plants don't last forever. After about three years, crops thin out and the berries shrink. The good news: every summer your plants send out long stems with baby plants on the end, and those give you free replacements. Here's how to turn them into a fresh bed.

Why renew from runners

Strawberries are short-lived. They crop best in their second and third years, then tail off — the plants get woody, congested and prone to disease. The fix isn't to buy new plants every few seconds: it's to grow your own from runners, the trailing stems that appear after fruiting.

A runner is a long, leafless stem that snakes out from the parent plant. Along it sit little tufts of leaves — baby plants, or "plantlets" — each ready to root where it touches soil. One healthy plant can throw out several, so a small bed quickly gives you all the replacements you need, for nothing.

Doing this every year keeps your strawberry bed productive. For the full growing routine, see the main strawberry guide.

How to peg them down

The trick is to root the plantlets while they're still attached to the parent. The parent keeps feeding and watering them until they've grown their own roots — much more reliable than snipping a runner off and hoping.

You have two options:

• Into pots (best for control). Sink a 7–9cm pot of multipurpose compost into the soil next to the parent, so the rim sits at ground level. Rest the first plantlet on the compost and hold it down.
• Straight into the soil. If your bed has space, just press the plantlet onto firm, weed-free ground where you want it.

Use a plantlet near the parent — the first one along the runner — and leave the trailing end of the runner intact. Pin it in place with a U-shaped piece of galvanised wire, a bent paperclip, or a small stone. Keep the compost or soil damp; it should root in three to five weeks.

When to cut them free

After three to five weeks, give a plantlet a gentle tug. If it resists, it has rooted. Snip the runner that joins it to the parent, leaving a short stub on the new plant.

Lift potted ones once they've filled their pot with roots, usually by late August or early September. Plant them into their final spot while the soil is still warm — this lets them settle in and build a crown before winter, ready to crop properly the following summer. Don't expect a full harvest in their first season; pinch off early flowers so the plant puts its energy into roots.

Choosing healthy parents and avoiding disease

This is the one rule that matters most. Only take runners from healthy, vigorous plants — never from anything with mottled or distorted leaves, stunted growth or poor crops. Strawberries carry viruses that spread straight down the runner, so a sickly parent gives you sickly offspring.

A few sensible habits:

• Mark your best two or three croppers in early summer and take runners only from those.
• Skip any plant that looked weak or yielded badly.
• After about five years of home-propagating, buy in fresh certified virus-free plants from a supplier such as Suttons or Thompson & Morgan to reset the bloodline.

Strawberries are prone to grey mould and crown rot, so keep new plants off soggy ground and don't crowd them — good airflow and decent drainage do most of the work.

Potting up

If you don't have a spot ready in the open ground, pot your new plants on into 1–2 litre pots of fresh peat-free compost and grow them on for a few weeks. They'll be sturdier when you finally plant them out, and you can overwinter them in a sheltered corner if needed.

Runners are also the easiest way to start a container display — they slot neatly into troughs, hanging baskets and grow bags. For sizes, spacing and watering in pots, see growing strawberries in pots.

Whatever you do with them, water new plants in well and keep them moist until they're growing away. From there, the standard care in the strawberry guide takes over — and you've renewed your bed for free.

If you'd rather start a brand-new bed from scratch, certified plants are worth it: