How to grow sweet corn in a raised bed

Corn picked minutes before dinner is a different vegetable to anything from a shop. It's a hungry, thirsty crop, and a raised bed's rich mix suits it — just plant it in a block, not a row.

Quick facts

• Position: full sun, 6+ hours
• Spacing: 30 cm apart, in a block
• Tub depth: our 35 cm depth
• Time to harvest: 12–16 weeks

When should I plant sweet corn?

Sweet corn is frost-tender — plant from spring through summer once it's warm. Our free garden calendar shows the right months for your postcode.

• Subtropical (Brisbane & SEQ): August to January
• Temperate (Sydney, Melbourne, Adelaide, Perth): September to December
• Cool & mountain (Tasmania, Canberra, highlands): November to December
• Tropical (Cairns, Darwin): April to September
• Arid inland: September to November

How do I grow sweet corn in a raised bed?

Plant in a block of short rows rather than one long row — corn is wind-pollinated, and a block sets fuller cobs. Sow directly into warm, rich mix.

How often should I water and feed sweet corn?

Corn is thirsty and hungry — water deeply and consistently, especially as the cobs fill, and feed well. A raised bed holds the moisture and nutrients they need.

What pests attack sweet corn?

Keep an eye out for caterpillars, cutworms and aphids. Most are easily managed — see our safe pest guide.

What diseases affect sweet corn?

The main ones are rust. Good airflow, morning watering and steady moisture prevent most.

What grows well with sweet corn?

Beans and pumpkins are the traditional 'three sisters' companions; beans even feed the corn. See our companion planting guide.

When do I harvest sweet corn?

Pick when the silks have browned and a squeezed kernel runs milky, not clear. Eat it as fresh as you can — the sugars turn to starch within hours.

Plan your patch: our free garden calendar shows what to plant now where you live. Ready to grow? Browse our raised garden beds or build your own with the garden bed builder.

Image: Forest & Kim Starr, CC BY 3.0 US, via Wikimedia Commons.