Plant group
Bed depth and width, sun requirements, spacing, watering, rotation, and sowing seasons by climate zone for eleven common vegetable crops.
Last reviewed 12 March 2027
This page covers growing technique only: how to build the bed, how far apart to space plants, when to sow in each climate zone, and how to water. It does not discuss nutrition, diet or any property of vegetables other than how to grow them.
Most vegetables need only about 200 mm of workable soil; root crops such as carrots and potatoes do better with 300 mm. Depth beyond that is rarely the limiting factor. What matters far more is that the soil is loose enough for roots to move through and holds moisture without staying saturated.
Keep beds no wider than 1.2 m if they can be reached from both sides, or 600 mm against a wall. The reason is simple: soil that is walked on compacts, and compacted soil grows poor vegetables. A bed you can reach the middle of is a bed you never step in. Paths between beds should be at least 500 mm so a wheelbarrow fits.
Raised beds solve drainage problems and warm up faster in spring, which is useful in cool and subtropical districts. In arid gardens they are less helpful, because raising a bed exposes more surface to evaporation from the sides; there, an in-ground bed with plenty of organic matter and a thick mulch holds moisture better. Full detail on building a bed from scratch is in preparing a new garden bed.
Fruiting crops — tomatoes, capsicum, zucchini, beans, corn — need at least six hours of direct sun to produce properly. Leafy crops such as lettuce and silverbeet manage on four, and in warm districts actually prefer afternoon shade through summer. Check the position in winter as well as summer: a bed that gets eight hours in January may get two in June when the sun is low and the fence casts a long shadow.
Shelter from wind matters more than most people expect. A bed exposed to constant wind dries out fast, and tall crops such as corn and staked tomatoes take physical damage. A permeable screen on the windward side makes a substantial difference — see planting a windbreak.
Add compost or well-aged manure to vegetable beds every season, worked into the top 150 mm. This is the single most useful thing you can do for a vegetable bed, and it matters more in sandy soils, where organic matter is the only practical way to lift water-holding capacity. Compost that you have made yourself is described in making compost at home.
Use fresh manure only on empty beds, well ahead of planting, and let it break down for at least six weeks. Fresh manure worked in immediately before sowing causes forked roots in carrots and burns young seedlings. Where a fertiliser is used, a slow-release complete fertiliser applied at the start of the growing season is sufficient for most home beds; this site does not recommend brands or give dosage schedules.
Overcrowding is the most common fault in home vegetable beds. Plants sown at full seed-packet density and never thinned compete for light, water and root space, and the result is a bed of small, slow plants rather than a bigger harvest. Thinning feels wasteful and is not.
Crowding also stops air moving through the bed, so foliage stays wet for longer after rain and dew. In humid subtropical and tropical gardens this is the difference between healthy foliage and foliage that collapses. Space more generously in humid districts than a general guide suggests.
Water at the base of plants rather than over the foliage, in the morning rather than the evening, and deeply rather than frequently. Wet leaves overnight are the main avoidable problem in a vegetable bed. A drip line under mulch delivers water where it is needed with the least loss and the least foliage wetting, and in dry-summer districts it turns daily watering into a weekly check.
Consistency matters as much as volume. Fluctuating soil moisture is what splits tomato fruit, causes bitter lettuce and makes root crops crack. Mulch between plants at about 25 mm once seedlings are established — enough to buffer the soil, not so much that it smothers small plants.
Do not grow the same family in the same bed year after year. The practical rotation for a home garden is four groups: leaf crops (lettuce, silverbeet, brassicas), fruiting crops (tomato, capsicum, zucchini, corn), root crops (carrot, potato), and legumes (beans, peas). Move each group on one bed each year. This breaks the build-up of soil-borne problems that affect one family and evens out the demands placed on the soil.
Legumes are worth including in the rotation deliberately, because they fix nitrogen in the soil and leave the bed in better condition than they found it. Follow beans or peas with a leaf crop to make use of it.
Where a bed is empty over winter, sow a green manure crop rather than leaving bare soil. It suppresses weeds, holds the surface against rain, and can be dug in before it sets seed.
The timing differs sharply across the country. In the tropics the main season for tomatoes, capsicum, beans and corn is the dry, roughly May to August, with leafy crops in raised beds through the wet. In the subtropics winter is the strong season and summer needs generous spacing. In temperate districts both seasons work, with warm-season crops going out after the last frost. In cool districts, start warm-season crops indoors in August and wait for soil to warm before sowing direct. In arid gardens the cool season is the productive one, with shade cloth over summer beds.
This site does not cover pesticides, herbicides or fungicides in any form. In a vegetable bed the practical alternatives are cultural and physical: rotate crops so nothing builds up in one place, space plants for air movement, water at the base so foliage stays dry, remove affected leaves and drop them in the bin rather than the compost, use fine netting or mesh barriers over vulnerable crops, and hand pick where that is practical. Weeds are managed by mulch, by hand weeding while they are small, and by not leaving bare soil.
Heights and spreads below are working dimensions for spacing purposes.
Solanum lycopersicum
Plant out only after the last frost in your district, setting the stake at planting rather than driving it in later through the root ball. Space 600 mm apart. Water at the base and keep soil moisture even; irregular watering is what splits fruit and causes dark sunken patches at the base.
Zones: tropical, subtropical, arid, temperate, cool
Beta vulgaris subsp. cicla
The most forgiving leafy crop grown in Australia and productive over many months. Cut outer leaves at the base and leave the growing centre alone, and one planting will keep producing through two seasons. Space 400 mm apart. Tolerates part shade and light frost without difficulty.
Zones: tropical, subtropical, arid, temperate, cool
Lactuca sativa
Sow in succession every three weeks rather than all at once, or the whole planting matures in the same fortnight. Heat and dry soil push plants to run to seed within days. In warm districts grow it in part shade through summer and in full sun through the cooler months.
Zones: tropical, subtropical, arid, temperate, cool
Phaseolus vulgaris
Sow direct into warm soil at about 100 mm spacing; the seed rots rather than germinating slowly in cold wet ground, so wait for soil warmth rather than air warmth. No transplanting — beans resent root disturbance. A second sowing three weeks after the first extends the picking season.
Zones: tropical, subtropical, arid, temperate, cool
Cucurbita pepo
Allow a full square metre per plant; crowding is the usual reason a zucchini bed underperforms. Water the soil rather than the leaves, and water in the morning so foliage dries. Pick fruit small and often, because a single fruit left to size up slows the whole plant down.
Zones: tropical, subtropical, arid, temperate, cool
Daucus carota subsp. sativus
Sow direct into deep, stone-free, sandy soil and thin seedlings to 50 mm apart once they are up. Do not transplant, and do not add fresh manure to the bed beforehand — both produce forked and twisted roots. Keep the soil surface damp until germination, which is slow.
Zones: tropical, subtropical, arid, temperate, cool
Brassica oleracea var. italica
A cool-season crop that bolts in heat, so time it for a winter harvest rather than a summer one. Space plants 500 mm apart. Cut the main head while the buds are still tight; several smaller side shoots follow over the next few weeks if the plant is left in the ground.
Zones: subtropical, arid, temperate, cool
Capsicum annuum
Slow to start and needs warm nights to set fruit, so it goes in later than tomatoes. In cool districts it does better in a large pot against a north-facing wall than in an open bed. Stake it: the stems are brittle and a plant carrying fruit splits at the fork in wind.
Zones: tropical, subtropical, arid, temperate
Zea mays
Plant in a block of at least four rows rather than a single line. Corn is wind pollinated, and a single row pollinates poorly, which is why cobs fill unevenly with gaps. Space 400 mm apart within rows and 700 mm between rows, and keep water up during the weeks the cobs are filling.
Zones: tropical, subtropical, arid, temperate
Pisum sativum
Sow direct in autumn with the trellis already in place, because peas resent being moved once they have started climbing. Space 50 mm apart along the support. They tolerate frost and cold soil better than almost any other crop, which makes them the reliable cool-season climber.
Zones: subtropical, arid, temperate, cool
Solanum tuberosum
Plant certified seed potatoes 150 mm deep and mound soil or straw over the stems as they grow so developing tubers stay covered. Tubers exposed to light turn green, so keep the mound topped up as the plants grow. Allow 300 mm between plants and lift the crop once the tops have died down.
Zones: subtropical, arid, temperate, cool
Wear gloves when handling soil and compost, and eye protection when using a fork or mattock. Keep tools clear of paths where they can be stepped on. In an emergency call 000.