August is the month gardeners most often write off — and the month that quietly decides how good next spring will be. The soil is warm, the watering can is already in your hand, and every gap left by a lifted onion or a finished bean row is an invitation. Sow now and you get two harvests in one: fast salads and winter greens for the months ahead, plus hardy annuals and biennials that sit tight over winter and flower weeks earlier than anything sown in March. Here is exactly what to sow in August, and how to get it up in hot, dry ground.
- Winter salads the last big sowing window
- Autumn greens spinach, chard & oriental leaves
- Hardy annuals sow now, flower early next June
- August rule sow shallow, water deep, shade young
Why August sowings work so well
Two things change in August. Soil temperature is still high, so germination is fast — often three to five days rather than the three weeks a March sowing takes. And day length is shortening, which means the crops that bolted the moment you looked at them in June (coriander, pak choi, spinach) now behave themselves and make leaf instead of flower. That combination is why experienced growers treat August as a second spring rather than the end of the season.
The catch is moisture. Warm soil dries out from the top down, and a seed drill that dries out at day two is a failed sowing. Water the drill before you sow, cover with dry soil, and keep the surface damp until seedlings are through — the same tactics that get you through a heatwave. Most August sowing is straightforward direct sowing; no windowsill required.
Vegetables to sow in August
- Salads, still on repeat — lettuce (winter-hardy types from mid-month), rocket and radishes. Short rows every two weeks right through the month.
- Leaves for autumn and winter — spinach is at its best sown now, and chard sown in early August crops until hard frost and again in spring.
- Oriental greens in their element — pak choi, mizuna and mustard practically stop bolting after the solstice. The whole Asian greens range is an August speciality.
- Cold-season salads — corn salad, endive and chicory sown now give you leaves when the shops are selling imported bags.
- Roots, with an eye on the clock — early August is the last comfortable call for fast turnips and baby beetroot; carrots sown in the first week can still make small autumn roots under a fleece.
- Thinking ahead — spring onions sown in late August overwinter for an early crop, and onion seed can go in for overwintering in mild gardens.
If in doubt, choose speed: anything in the fast-growing vegetables range will finish before the light runs out, and you can browse everything tagged for this month in the August sowing collection. The vegetable sowing calendar gives every window at a glance.
Herbs to sow in August
August is one of the best herb-sowing months of the year, precisely because the heat-shy annuals stop panicking. Coriander sown now runs to leaf rather than seed, dill gives a tender late flush, and chervil is a genuine autumn-and-winter herb that resents spring sowing. A row of parsley sown in early August germinates in a fortnight and carries you through to next May. Watercress is happy in a damp pot on a shaded step. Browse the full herb seed range and check the herb sowing calendar for exact timings.
Flowers to sow in August: the head start that shows
This is the real prize of the month. Hardy annuals sown in August germinate in warm soil, make a sturdy rosette before winter, and flower four to six weeks earlier — and on much bigger plants — than the same seed sown next spring. Cut flower growers plan their whole year around this sowing.
- Hardy annuals for early cutting — nigella, larkspur, cornflowers, ammi, calendula and poppies are all classic autumn-sown performers.
- Biennials, last call — foxgloves, wallflowers, sweet william and forget-me-nots sown in the first half of August still make good plants for next May. Our step-by-step guide to sowing biennials covers the timing in detail.
- Perennials from seed — scabiosa and delphiniums sown now establish roots before winter and flower in their first full season.
- For the vase — if you are building a cut flower garden, August is the sowing that fills the hungry gap in early June. See the cut flower range and the flower sowing calendar.
One August afternoon: a simple sowing plan
- Clear a finished crop Lift spent onions, garlic, peas or bolted lettuce — that bare bed is the whole opportunity.
- Rake and refresh A light forking and a scatter of compost is plenty; see preparing your soil.
- Flood the drill first Soak the seed drill, sow into wet soil, then cover with dry soil to seal the moisture in.
- Sow shallow and short Half the depth you would use in spring, and short rows of several crops rather than one long one.
- Shade, then watch Shade cloth or a plank over the row until seedlings appear, and check daily in hot weather.
Sowing to eat, or sowing to flower?
Every August sowing belongs to one of two plans, and it helps to know which you are making:
Sow to eat this autumn & winter
Fast, leafy and cold-tolerant — ready in 4–10 weeks.
- Spinach, chard & winter lettuce
- Pak choi, mizuna & mustard
- Rocket, radish & corn salad
Sow to flower next spring
Overwintering plants that flower early and big.
- Nigella, larkspur & cornflower
- Foxgloves, wallflowers & sweet william
- Ammi, scabiosa & forget-me-nots
Common August sowing mistakes
- Sowing as deep as you would in spring — deep drills dry out and bake. Sow shallow and cover lightly, then keep the surface damp.
- Watering little and often — a daily splash wets the top centimetre and nothing else. One good soak beats five sprinkles; the watering guide explains why.
- Leaving the biennials until September — foxgloves and wallflowers sown after mid-August rarely make a big enough plant to flower well. Early August is the last honest window.
- Starting long-season crops — tomatoes, squash, sweetcorn and beans will not finish now. Put those packets away properly instead; see storing seeds for next season.
- Sowing it all at once — August still rewards succession sowing: a short row every fortnight keeps salads coming into November.
Frequently asked questions
Is it too late to sow vegetables in August?
No. Salads, spinach, oriental greens, rocket, radishes and corn salad all crop from an August sowing, and several of them overwinter for an early spring picking. Anything from the fast-growing range will finish comfortably.
What flowers should I sow in August?
Hardy annuals — nigella, larkspur, cornflower, ammi, calendula and poppies — plus the last of the biennials such as foxgloves and wallflowers in the first half of the month. All of them flower earlier and bigger than a spring sowing.
Do I need to sow indoors in August?
Rarely. Soil is warm enough for direct sowing everywhere. Trays are useful for biennials and hardy annuals if slugs are a problem, or if you want to plant out into a bed that is still occupied. Microgreens and sprouts are the one indoor option worth having year-round.
Why did my August sowing fail to come up?
Almost always dryness at germination, occasionally soil that was simply too hot for lettuce. Water the drill before sowing, shade the row, and keep the surface damp for the first week.
August is not the end of the sowing year — it is the start of the next one. Browse all our vegetable seeds and flower seeds, or take your time with the rest of our growing guides. If you sow one thing this month, make it a row of spinach and a tray of foxgloves: one feeds you in October, the other repays you every morning next June.
