Gardening

What to look forward to from your garden in May

With two bank holiday weekends in May, we’ve got plenty of time to get out into the garden. There’s lots to plant as the danger of frosts passes and the long days and warm temperatures see everything growing strongly.

Water anything newly planted during dry spells for the first couple of months to help it settle in. A neat technique I use mid-month is the Chelsea chop, where I cut back perennials such as sedum, phlox and hardy geraniums by half their height to create bushier plants.

Ceri Thomas

Which? Gardening Editor

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 Plant tender plants outdoors

By mid-May, most areas are frost-free and it’s safe to plant tender plants outdoors. Keep an eye on the local forecast and have some fleece at hand to cover up plants if you get an unexpected cold night. As well as border plants, such as dahlias, you can put out patio pots and tender veg, such as courgettes.

Protect your plants with Best Buy fleece

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Top jobs for May

Fill your patio and borders with colour for the summer months ahead

Take out spring bedding and replace with summer plants

Plant leeks among spring veg that will be removed soon

Trim back the new growth of wall-trained pyracantha

Take off fleece when the weather warms up

More gardening jobs for May

 How to buy the best: Robot mower

If the thought of another summer cutting the lawn fills you with dread, a robot mower is well worth considering. Once set up, it will make the grass look like a carpet of green and even dispose of the clippings into the turf, so there’s nothing for you to worry about.

See the models that impressed us

 Sow beans

Wait until mid-month before sowing French and runner beans, or they’ll be ready before it’s warm enough for them to go outside and will turn yellow. We recommend growing no more than 12 plants of climbing beans to avoid gluts.

Try our tips for growing runner beans

Expert advice

Help pollinators

Some traditional patio favourites, such as pelargoniums and fuchsias, may not attract many pollinators – but there are some colourful alternatives that do. Try bidens, coreopsis, monarda, scabious and nicotiana.

 The best patio plants to attract butterflies and bees

 Plant tomatoes

Tomatoes do best in the ground, either in the greenhouse border or the veg patch. Alternatively, plant in a 40L pot using a Best Buy compost for patio pots. We find that growing bags can be variable in quality. If you want to use one, have one plant per 10L of compost.

Read more advice about growing tomatoes

How to control box caterpillar

The striped yellow and green caterpillars are out in force, eating the leaves of the popular evergreen box shrub. The best way to control them is to pick them off the plant. They often hide inside, so take your time to find them all.

Other ways to tackle this pest

 Still time to sow

Look forward to colour in your garden by sowing sunflowers, zinnias, cosmos and marigolds indoors, ready to plant out later in the month. They’ll soon catch up with earlier-sown plants.

Try a Best Buy compost for sowing seeds

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