The Autumn Changeover: Summer Beds to the Winter Patch

Raised timber beds planted with young onions

The short version: Change over one bed at a time. Keep summer plants still worth picking, bin sick ones and compost tired ones. Sow winter seedlings in trays a few weeks before a bed empties. Feed each cleared bed with compost, lime only if a pH test says so, follow an unrelated plant family, and sow a cover crop on any bed left empty for winter.

Late summer creeps up. The tomatoes are still colouring, the zucchini has gone grey with mildew, and the broccoli seed is waiting for room that does not exist yet.

Skip the one big clear-out. Work bed by bed, and winter crops go in as summer ones finish.

Stay or go: judge each summer plant

Producers stay, sick plants come out first, tired ones go to compost. Sick means wilting in moist soil or mottled, bronzed young leaves; tired means clean but sparse.

Tomatoes: once cool nights stop fruit setting, pick fruit showing first colour to ripen indoors (see our tomato guide).
Chillies and capsicums are perennials: prune and keep them in frost-free gardens, or see overwintering chillies.
Zucchini and cucumbers: keep a cropping plant with mild late mildew. Once the fruit stops, pull it, binning heavily mildewed vines.
Pumpkins stay until the skin resists a thumbnail and the stem turns corky, but come in before frost.
Beans: check one plant's roots first. If clean, cut the rest at soil level and leave the roots in; if galled, pull and bin the lot.

Knots that are part of the root and will not rub off mean root-knot nematode; nodules that rub off a bean root easily are the helpful nitrogen kind.

Swollen, galled roots of a plant affected by root-knot nematode — Nematode galls are part of the root and will not rub off. Bean nodules sit on the surface and rub away easily.

What goes in the compost, and what does not

Home heaps rarely get hot enough to kill spores or weed seed, so compost clean spent plants and keep these out:

Diseased plants, roots included: bin them (see garden hygiene).
Fruit with fruit fly: freeze it sealed in a bag for at least two days, then bin it, not compost or green waste (see our fruit fly guide). In Tasmania and South Australia, report it instead to Biosecurity Tasmania on (03) 6165 3777 or the Fruit Fly Hotline on 1300 666 010.
Seeding weeds and runners such as couch: drown them in a bucket for a few weeks before composting, or bin them.

Bought manure, straw and compost can carry herbicide residue that twists young tomatoes, beans and peas: test each load with the three-week pea pot test in our herbicide residue guide.

Plan the winter bed by plant family

Related plants share soil pests, so follow each summer crop with something unrelated (see plant families and crop rotation). Four pairings cover most beds:

After beans: brassicas and leafy greens, which can use the little nitrogen the bean roots leave.
After tomatoes, zucchini or pumpkins: carrots, beetroot, onions or garlic on compost alone, since fresh manure forks carrots and gives onions soft, thick necks.
After nematode galls: onions, cabbage or cauliflower, which resist it, rather than carrots, lettuce or beans.
Where clubroot or onion white rot has shown: keep that family out for years: both persist up to 20 years in soil.

Test before you lime

Liming every autumn is a habit worth breaking. Test first with a cheap colour kit: most vegetables do best at pH 6.0 to 7.0 (see our soil pH guide).

Brassicas like 6.5 to 7.0. Below that, our broccoli guide suggests 100 to 200 g of garden lime or dolomite per square metre, checked against the label for your soil, four weeks before planting.
Potatoes are the exception: lime encourages common scab, so skip it where they will grow.

A changeover weekend, in order

Tray seedlings are ready four to six weeks after sowing, and a fed bed settles in about two. So sow trays two to four weeks before you clear. Test the pH early: a limed bed needs four weeks, so sow its trays on clearing day.

Chinese broccoli seedlings growing in black plastic cell trays — Plant tray seedlings at four to six true leaves, after a week of hardening off. Held much longer, brassicas can form a tiny button head and stall.

Harvest, then pull, weed and sort into compost, bin and weed bucket, flowering weeds first. Do not leave the pile by the bed to shelter slugs.
Feed and loosen. Spread 5 to 8 cm of compost, adding composted manure only where brassicas and leafy greens will go, and lime if the test called for it. For root crops, rock a fork in 25 to 30 cm without turning the soil, and rake out stones (see preparing garden beds).
Soak and check. Water still lying a day after a deep soak, or a sour smell when you dig, means fixing the drainage before carrots, onions or garlic, which rot in wet ground. Then mulch 5 to 7 cm deep, off seed rows until seedlings are up.
Plant once the bed has settled, after a week of hardening off, at four to six true leaves, before brassicas form a tiny button head and stall.

Sow field peas and oats on any bed resting over winter (see winter cover crops by climate zone). Where tomatoes wilted from soil disease, a biofumigant mustard, chopped and dug in as our biofumigation guide sets out, can lower some diseases. It is a brassica that can also host root-knot nematode, so keep it off galled, clubroot and cabbage-bound beds.

Oat and pea cover crop seed scattered on soil — Peas and oats protect and feed a bed that rests over winter.

Seed heads, water and slugs

Let some plants seed. Flowering coriander, dill and parsley draw hoverflies and parasitic wasps, calendula left to seed returns, and dried bean pods start your seed saving.
Keep watering through a dry autumn: carrot rows damp in the top centimetre until they come up, established brassicas 25 to 50 mm a week.
Watch for slugs and snails after autumn rain. Hand-pick after dark. If you bait, choose iron-based pellets, follow the label, scatter thinly and keep pets from the box and baited beds: any snail bait can poison a dog that eats enough.

When to change over in your zone

Tropical (Darwin in the Northern Territory, Cairns and Townsville in Queensland): change over as the wet ends, ahead of the May to September dry season. Tomatoes, brassicas, carrots and lettuce go in from April or May.
Subtropical (Brisbane and south-east Queensland, northern New South Wales): February to April, with brassica trays shaded from late summer sun.
Arid and semi-arid (Alice Springs in the Northern Territory, Broken Hill in New South Wales, Mildura in Victoria, Kalgoorlie in Western Australia): raise trays in shade from February and plant out once the heat breaks, around March in the southern inland and April in Alice Springs. Settle plants before frosts bite from May.
Temperate (Sydney and the New South Wales coast, Melbourne in Victoria): February to April, with brassica seedlings planted by Anzac Day so they head through winter.
Mediterranean (Perth and southern Western Australia, Adelaide in South Australia): the autumn break, the first soaking rain of the winter growing season, can come late. Plant out after it, or once the heat eases into a deeply watered bed.
Cool and alpine (Tasmania, Canberra in the ACT, Ballarat in Victoria, Orange and Armidale in New South Wales, Stanthorpe in Queensland): move first. Sow brassica trays from December to February and plant them into beds freed by garlic or peas. Clear tomatoes and pumpkins before the first frost.

These zones are broad groupings. Between two, lean on your local first frost date and What to Sow Now.

Handle compost and potting mix with care

Compost, potting mix and garden soil can carry Legionella, the bacteria behind Legionnaires' disease, a form of pneumonia caught by breathing in dust or droplets. The Victorian Government's Better Health Channel advises a mask and gloves, opening bags slowly away from your face, dampening the material and washing your hands.

Frequently asked questions

Should I pull a tomato that is still flowering in autumn?

Where frost is coming, pinch off late flowers, which have little time to ripen fruit, and pick the plant clean before frost. In frost-free tropical and subtropical gardens a healthy plant can keep cropping.

Can seedlings go into a bed I cleared today?

Into a gap left by a finished crop, topped with mature compost, yes. Leave a freshly fed bed about two weeks to settle.

Do I need to dig the whole bed over?

No: it breaks soil structure and lifts buried weed seed. Spread compost on top and fork only compacted soil or carrot beds.

What if I am not ready to plant for winter?

Sow a cover crop, or at least mulch, so bare soil is not left to winter rain and weeds.

Your winter patch can grow up in the spaces the summer one leaves.

Related growing guides

Browse our autumn and winter seeds and cover crop seeds. Most cover crop mixes cannot be sent to Western Australia or Tasmania, and pea seed cannot go to Tasmania.