Posted by Tom Steel on 1st Aug 2025

Gardening Jobs for August

The height of summer is still here, but beyond basking in barbeque-worthy weather, your garden needs attention. August is usually one of the hottest months of the year, making watering and general care more important than ever.

This month is all about maintenance, late sowings and smart planning. From the best choices to plant in August to essential jobs around the garden, here are our top tips to keep everything looking good and growing strong through the rest of the summer.

What to plant in August

Sow hardy biennials for next spring

Get a head start on next year’s display by sowing wallflowers, foxgloves, honesty or sweet williams. Sown now, they’ll root well before winter and bloom beautifully come spring.

Plant autumn-flowering bulbs

Now’s the moment to tuck in colchicums, nerines and sternbergia. These bulbs bloom in early autumn - bringing fresh colour just as summer flowers begin to fade.

Add evergreen shrubs or climbers

August is a great time to plant container-grown evergreens like viburnum or climbing jasmine. Warm soil supports root growth, and regular watering will help them settle in before cooler weather.

Fill seasonal gaps with late performers

As early summer stars like poppies and alliums fade, refresh tired displays by adding pots of dahlias, upright fuchsias, patio lilies or tall late perennials. These will keep your garden vibrant well into autumn.

New for this summer, we have an exclusive range of J. Parker’s own perennial plants available in 1 Litre + pots. Just pop them into your beds, borders or containers and enjoy instant impact.

Garden jobs in August

Prune wisteria

Now’s the time to give summer-pruned wisteria a tidy-up by cutting back long, whippy side shoots to about five or six leaves. This keeps growth in check and encourages more flower buds for next spring.

Tip: Use clean, sharp secateurs and cut just above a leaf joint to avoid dieback.

Summer prune trained fruits

Prune trained apple and pear trees - like cordons, espaliers and fans - by shortening side shoots to about three leaves above the basal cluster. This keeps their shape tidy and encourages fruit bud development for next year.

Tip: Avoid pruning stone fruits like plums or cherries now, as they’re prone to silver leaf disease.

Deadhead flowering plants regularly

Keep borders and containers looking their best by removing spent blooms from dahlias, roses, cosmos and more. Regular deadheading encourages continuous flowering into early autumn.

Tip: Snip just above a strong leaf set to help the plant redirect energy into fresh blooms.

Water containers and new plants

In hot, dry weather, pots and young plants need regular watering - ideally in the early morning or evening to minimise evaporation. Use rainwater or greywater where possible to save resources.

Tip: Add mulch to pots or borders to help retain moisture and reduce how often you need to water.

Collect seed from garden plants

Gather ripe seed from annuals and perennials like nigella, calendula or aquilegia for sowing next season. Choose a dry day and paper bags or envelopes for storage.

Tip: Label your seeds and store them somewhere cool and dry to keep them viable.

Improve soil with green manures

If a veg bed is empty, sow green manures like mustard, phacelia or clover to boost soil structure and fertility. They also help suppress weeds and protect bare ground.

Tip: Cut back before flowering and dig in well ahead of your next planting.

Keep ponds and water features topped up

Hot weather can lower water levels quickly, so top up ponds and water features regularly - preferably with rainwater. Check pumps and remove algae or blanket weed as needed.

Tip: Top up early or late in the day to avoid temperature shock for pond life.

What vegetables to plant in August

Spinach

Varieties to try: Spinach Perpetual is a hardy, slow-to-bolt variety perfect for sowing in late summer. It’s great for repeat harvests into autumn and can even keep going through winter in milder areas.
Growing tips: Sow seeds thinly in shallow drills in fertile, moisture-retentive soil, ideally in full sun or partial shade. Keep the soil consistently moist to prevent bolting, and thin seedlings to 7-10 cm apart as they develop.
Harvesting: Pick outer leaves once they reach about 7-10 cm. Regular harvesting encourages fresh growth and extends cropping. Young leaves are perfect raw in salads, while mature leaves work well cooked.

Lettuce

Varieties to try: Lettuce Romaine Parris Island Cos forms upright, crunchy heads with excellent flavour and good bolt resistance - a reliable choice for August sowing.
Growing tips: Sow seeds sparingly in rows or containers of free-draining compost. Place them in a sunny or lightly shaded spot, and keep the soil consistently moist. Once seedlings are growing well, thin them out to 20-25 cm apart to allow space for heads to form.
Harvesting: Cut whole heads when mature or pick outer leaves as needed. This variety is great for Caesar salads and holds up well to late summer heat with a bit of shade.

Rocket

Varieties to try: Wild Rocket has a spicy, peppery flavour and better resistance to bolting than standard rocket, making it ideal for sowing in August.
Growing tips: Sow directly into beds, containers or window boxes. Choose a lightly shaded spot if possible to reduce heat stress. Keep soil moist and weed-free while seedlings establish.
Harvesting: Start picking young leaves after 3-4 weeks. Regular harvesting helps prevent flowering and keeps leaves tender. Best enjoyed fresh in salads or as a garnish.