Ask any experienced Adelaide gardener and they will tell you the same thing: autumn, not spring, is the real planting season in South Australia. After months of punishing heat, the arrival of cooler nights and the first autumn rains creates almost perfect growing conditions. The soil is still warm from summer, which encourages fast root growth, while milder days mean new plants aren't stressed by heat. Plants put in now have the whole of winter to establish before facing their first summer.
This guide takes you through what to plant in each month of autumn in Adelaide - vegetables, herbs, flowers, bulbs, and native plants - so you can make the most of the season. Timings are for the Adelaide Plains; if you garden in the Adelaide Hills or other cooler areas, aim to plant a week or two earlier, before the first frosts arrive.
Why Autumn Is Adelaide's Best Planting Season
- Warm soil: Soil temperatures lag behind air temperatures, so in March and April the ground is still warm enough for rapid root development.
- Reliable rain: Adelaide receives most of its rainfall between May and September, giving new plantings natural watering through their establishment period.
- Less stress: Mild days and cooler nights mean less transplant shock and fewer losses than spring plantings, which must survive a summer before they're established.
- Fewer pests: Many summer pests decline as temperatures drop, giving young plants a better start.
March: The Changeover Month
March in Adelaide often still delivers hot days, so treat it as a transition month. Clear out tired summer crops, prepare beds, and start sowing the first cool-season plants once the worst of the heat has passed.
Vegetables to Plant in March
- Leafy greens: Lettuce, spinach, rocket, and Asian greens such as bok choy germinate quickly in warm soil.
- Root vegetables: Sow beetroot, carrots, and radishes directly into well-prepared beds.
- Brassica seedlings: Start broccoli, cauliflower, cabbage, and kale in punnets or trays for transplanting in April. In the Hills, transplant them now.
- Peas: Late March is a good time for a first sowing of snow peas and sugar snap peas.
Our dedicated SA autumn vegetable planting guide covers every crop in detail, with spacing, companion planting, and regional timings.
Herbs to Plant in March
Coriander is notoriously difficult in an Adelaide summer, bolting to seed almost as soon as it germinates - but sown in autumn it grows lush and leafy for months. Parsley, chives, dill, and chervil also establish well now. Perennial Mediterranean herbs such as rosemary, thyme, oregano, and sage can be planted any time in autumn and will be well established by summer.
Flowers to Plant in March
Many Adelaide gardeners follow the old tradition of sowing sweet peas around St Patrick's Day in mid-March. Sow them directly against a trellis or fence in a sunny spot for fragrant flowers through late winter and spring. March is also a good time to sow seeds of calendula, cornflowers, and nigella for spring colour.
Bulbs to Plant in March
Freesias are one of the easiest bulbs for Adelaide gardens and should go in during late summer and early autumn. Plant corms about 5 centimetres deep in a sunny spot with good drainage for fragrant spring flowers.
April: Peak Planting Time
April is the busiest and most rewarding month in the Adelaide garden. Temperatures are reliably mild, the soil is still warm, and the first decent rains usually arrive. If you only plant in one month of the year, make it April.
Vegetables to Plant in April
- Brassicas: Transplant broccoli, cauliflower, cabbage, kale, and Brussels sprouts seedlings.
- Garlic: April is the traditional month to plant garlic in SA for harvest in late spring or early summer.
- Broad beans: Sow directly into beds. They are one of the most reliable winter crops in Adelaide and improve the soil as they grow.
- Onions: Plant onion seedlings now for a late spring harvest.
- Strawberries: Autumn is an excellent time to plant new strawberry runners so they establish over winter and fruit well in spring.
- Leafy greens: Continue successive sowings of lettuce, spinach, and silverbeet.
Flowers to Plant in April
April is the month to fill your garden with winter and spring colour. Pansies, violas, and primulas bring cheerful colour through the coldest months, while snapdragons, stocks, Iceland poppies, and sweet alyssum provide a burst of flowers in late winter and spring. Plant seedlings in a sunny position, water them in well, and feed every few weeks with a liquid fertiliser for continuous flowering.
Bulbs to Plant in April
Most spring bulbs can go in from April. Daffodils and jonquils are especially reliable in Adelaide and will naturalise in a sunny, well-drained spot, returning year after year. Other good choices include Dutch iris, ranunculus, anemones, and sparaxis. As a general rule, plant bulbs at a depth of two to three times their height.
Natives to Plant in April
Autumn is the best time of year to plant Australian natives in South Australia. Roots establish over the wet winter months, giving plants the best possible chance of surviving their first summer with minimal watering. Grevilleas, correas, emu bushes, native grasses, and ground covers all do well planted now. Our guide to the top 20 native plants for SA gardens has plenty of ideas.
Trees and Shrubs to Plant in April
Container-grown trees and shrubs establish well in autumn. It is a particularly good time to plant citrus in frost-free parts of Adelaide, giving roots time to settle before the growth flush of spring - see our guide to growing citrus in Adelaide for variety advice. Drought-hardy Mediterranean shrubs such as lavender, rosemary, and westringia are also excellent choices now.
May: Settling In for Winter
By May, days are noticeably shorter and the first cold snaps arrive. Growth slows, but there is still plenty to plant - especially cold-hardy crops, bulbs that benefit from cooler soil, and anything that needs winter rain to establish.
Vegetables to Plant in May
- Peas: A final sowing of snow peas, sugar snaps, and shelling peas early in the month.
- Hardy greens: Kale, silverbeet, spinach, and rocket continue to grow through winter.
- Turnips and swedes: These often-overlooked root vegetables thrive in cool conditions.
- Spring onions and leeks: Slow-growing but reliable through the cooler months.
- Broad beans: There is still time for a second sowing for a staggered spring harvest.
Bulbs to Plant in May
Tulips need a period of cold to flower well, which Adelaide's mild winters don't always provide. For best results, place tulip bulbs in a paper bag in the vegetable crisper of your fridge for around six weeks (away from fruit, which releases ethylene), then plant them in May once the soil has cooled. Hyacinths benefit from the same treatment. Daffodils and jonquils can still be planted early in the month.
Flowers and Ground Covers to Plant in May
Continue planting winter-flowering seedlings such as pansies, violas, and primulas. May is also a good time to establish native ground covers and grasses in areas you want to convert from lawn, letting winter rain do the watering for you.
Preparing for Winter Planting
Late May is the time to plan for bare-rooted plants, which arrive in nurseries in winter. Prepare the planting holes now for roses, deciduous fruit trees, and ornamental trees so you can plant them as soon as they are available.
Autumn Planting Tips for Adelaide Gardens
Prepare Your Soil First
After a long summer, most Adelaide soils are depleted and dry. Before planting, dig in a generous layer of compost or well-rotted manure to improve structure and water-holding capacity. Our composting guide explains how to make your own. For heavy clay soils, adding gypsum alongside organic matter helps open up the structure.
Water Until the Rains Arrive
Autumn rain in Adelaide is often unreliable until May. Keep new plantings watered regularly until consistent rain arrives - a deep soak two or three times a week is better than a daily sprinkle. Check soil moisture with your finger before watering.
Mulch After Planting
Apply a layer of mulch around new plantings to keep the soil warm, suppress weeds, and hold moisture. Use a fine mulch such as pea straw or sugar cane around vegetables and annual flowers, and a coarser mulch around shrubs and natives.
Watch for Snails and Slugs
Cooler, damper weather brings snails and slugs out in force, and they can destroy young seedlings overnight. Check plants in the evening, use beer traps or copper barriers, or choose pet-safe iron-based baits if needed.
Don't Forget Maintenance
Autumn is also the time for pruning, lawn renovation, and preparing your garden for winter. Our autumn garden maintenance checklist covers everything you need to do between March and May.
Start Planting This Autumn
Autumn rewards the gardeners who get in early. Whether you're filling a veggie patch, adding colour with bulbs and annuals, or planting natives that will look after themselves for years, the work you do between March and May sets your garden up for the year ahead.
Find the right plants for your conditions with the GardeningSA plant finder, locate local nurseries in our SA gardening directory, and browse our full library of guides for more seasonal advice tailored to South Australian gardens.