Growing Swiss Chard in Containers

Quick facts

  • Full-size plants: a pot at least 40 cm wide and 40 cm deep

  • Baby leaves: troughs and window boxes work, with plants about 5 cm apart

  • Compost: multi-purpose compost

  • Position: sun or light shade

  • Harvest: from summer through winter into spring

  • Key moment: keeping the compost damp, as dry pots make chard bolt

Swiss chard earns its place on a patio twice over. The glossy leaves and bright red, yellow, orange or white stalks look as good as many ornamental plants, and you can pick from the same pot for months. It's happy in a bit of shade, rarely needs feeding and shrugs off winter, which makes it one of the easiest vegetables to keep going in a container.

Full-size plants or baby leaves?

  • Full-size chard gives large leaves and chunky, colourful stems for cooking. It needs a big, deep pot, as the roots go down further than you might expect.

  • Baby leaf chard is sown close together and picked small for salads. It suits shallower troughs and window boxes, and you can resow every few weeks.

Choosing a container

For full-size plants:

  • at least 40 cm wide and 40 cm deep

  • one plant per 40 cm pot, or several in a long trough spaced 30 cm apart

  • drainage holes in the base, with the pot raised on feet or bricks

For baby leaves: any container with drainage holes, including window boxes and troughs, with plants about 5 cm apart.

For more on choosing pots for vegetables, see growing vegetables in containers

Choosing a variety for pots

For a colourful display, 'Bright Lights' gives a mix of red, yellow and orange stalks, and 'Rhubarb Chard' has vivid red ones. Both hold the RHS Award of Garden Merit. If your pots will sit out through a cold winter, a white-stemmed variety such as 'Fordhook Giant' is the hardiest choice.

Chard also looks good planted alongside flowers and herbs in a mixed container, as long as the pot is big enough.

Sowing Swiss chard in containers

  1. Fill the pot with multi-purpose compost and water it.

  2. Sow seeds about 2.5 cm deep, from April to July.

  3. Each seed usually produces several seedlings. Thin them in stages, eating the extras as baby leaves, until full-size plants are 30 cm apart or baby leaf plants about 5 cm apart.

You can also raise seedlings in modules from early spring and plant them into the pot once they're about 5 cm tall.

For sowing times, see when to plant Swiss chard in the UK

Watering container Swiss chard

Chard in the ground copes with short dry spells, but chard in a pot doesn't. Compost dries out quickly, and a plant that goes short of water in summer is likely to bolt, sending up a flower stalk and turning its leaves tough and bitter. Check the pot every day or two in warm weather and water whenever the top few centimetres feel dry.

For more detail, see how often to water Swiss chard

Feeding container Swiss chard

Fresh multi-purpose compost holds enough food for the first few weeks. Chard in a pot is picked for many months, though, so once it's been cropping for a while, a general liquid feed every few weeks keeps new leaves coming.

Where to put container Swiss chard

A sunny spot gives the most leaves, but chard is one of the few vegetables that still crops well in light shade. That makes it useful for a patio corner or balcony that only gets sun for part of the day.

Container Swiss chard in winter

Chard is hardy and survives most UK winters outdoors, even in a pot. Growth slows right down in the cold. Moving the pot against a sheltered wall, or into an unheated porch or greenhouse, keeps the leaves in better condition and gives you a few more pickings through winter.

Harvesting container Swiss chard

Pick the outer leaves first, cutting them at the base of the stalk, and leave the small leaves in the middle to keep growing. A plant in a pot has fewer leaves than one in the ground, so take just a few at a time.

For more detail, see when to harvest Swiss chard

Common problems in containers

  • Bolting: usually a sign the compost dried out. Cut off the flower stalk and keep watering steady.

  • Slugs and snails: they climb into pots easily, especially after rain. Check under the rim on damp evenings.

  • Leaf miner: pale, blotchy tunnels in the leaves. Pick off and bin affected leaves.

If your plants are slow to get going, see why Swiss chard doesn't grow

For the whole growing season, see how to grow Swiss chard in the UK

Common questions

Can you grow Swiss chard in pots?
Yes. Full-size chard grows well in a pot at least 40 cm wide and deep, and baby leaf chard grows in troughs and window boxes. It's one of the easiest vegetables to grow in containers.

What size pot does Swiss chard need?
At least 40 cm wide and 40 cm deep for full-size plants. Baby leaves can be grown in shallower containers.

Can you grow Swiss chard in a window box?
Yes, for baby salad leaves. Sow them about 5 cm apart and pick them young. Full-size plants need a much deeper pot.

Why is my potted Swiss chard bolting?
Usually because the compost dried out. Chard in pots needs steady watering, especially in summer. Cut off the flower stalk to keep the plant cropping a little longer.

Container size, spacing, varieties and care based on RHS guidance.

 
laura tennant