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August in the garden

August in the garden - Blog Header

Your garden in August

It’s August and there’s plenty blooming in the garden this month. Flowers like dahlias, alstoemeria and zinnias are all at their peak in August. 


It’s the last official month of summer and it’s the perfect time to
enjoy your garden while it’s at its best. 

Schools out for summer, so you’ll be wanting to make the most of the garden you’ve worked hard on throughout the year.


Dahlia - August in the garden

Here’s our top tips that will keep your garden lush and vibrant throughout August:


Feel if the soil is moist and if dry around an inch deep, water thoroughly. Thorough watering supports plants for longer – just wetting the surface of the soil wastes water, encourages weeds and can lead to surface rooting making the plants more vulnerable.

Water early morning and late evening to avoid evaporation and to make sure that water is reaching the plant’s roots.

Pots, especially terracotta pots dry out more quickly than borders so be sure to keep them well-watered and feed with a liquid fertiliser every 10-14 days.

Water evergreen shrubs like camellias and rhododendrons thoroughly this month to make sure that next year’s buds develop well.

Trim lavender in August

Trim hardy lavender plants after they’ve finished flowering to prevent them from becoming leggy.

Give hedges and bushes a final trim before the end of summer to keep them neat before they stop growing.

Prune all summer flowering shrubs if they’ve finished blooming.

Keep on top of weeds, especially as we’ve had a particularly wet month so they’ll be growing quickly.

Deadhead annual bedding plants and perennials to encourage them to flower into the autumn and stop them self-seeding and cut back faded perennials.

Cut back herbs now to encourage a flush of tasty leaves you can harvest before the frost. Too many to use? Why not freeze them to use later!

Here are some tasks to keep you busy in the veg patch this month:

Aubergine plant august

Pinch out the tips of your runner bean plants once they
reach the top of their support. This encourages side-shooting and more beans at
a manageable height for picking.

Continue to feed tomato plants with tomato feed and remove
any stems and leaves that are growing lower than your first fruits.

Apply a high-potash fertiliser such as tomato feed once
fruits start to form on peppers, cucumber and aubergine plants.

Thin parsley to help it establish a good root system before
winter. Leave 25cm between each plant.

Pinch out the growing tips of your aubergine plants once they
have 5 or 6 fruits. Pick fruits while they’re young and shiny.


Start harvesting your main crop potatoes as the leaves yellow and die back. Store your potatoes in hessian sacks which block light but allow ventilation.

Lift and dry onions, shallots and garlic once the foliage has flopped over and yellowed.

Harvest French and runner beans regularly to prevent them from setting seed.

Divide established clumps of chives this month by gently lifting the plant from the ground and pulling apart into several plants. 

Keep an eye out for potato and tomato blight and remove and destroy any affected plants to prevent its spread. Look out for watery rotted parts on leaves which will turn brown and shrivelled. 

Clear away any diseased and spent foliage around your veg plants to discourage pests and diseases spreading.

There’s still plenty you can plant in August – both seeds and young plants, including:

  • Lettuce
  • Spinach
  • Spring onions
  • Rocket
  • Cabbages