Sweet corn is one of summer’s most enjoyable crops to grow. It’s fast, fun, and gives you the sweetest, most succulent cobs fresh from the garden. Here’s how to grow the very best!
Time your corn right
- Corn loves warm soil and sunny conditions.
- Spring to early summer is prime planting time in most areas. In tropical and warm subtropical regions, sweet corn can be grown year-round.
Prepare the Perfect Bed for corn
- Plant in a spot with full sun and protection from strong winds.
- Sweet corn is a heavy feeder, so enrich your soil with compost, well-rotted manure, and a good dose of blood and bone or pelletised chicken manure.
- If your soil is heavy, mound it into rows to boost drainage.
Sow Smartly
- Corn seed germinates easily, but it must be fresh.
- You’ll need at least 15 plants for a decent harvest. Plant two seeds per hole, 4-5cm deep. Once they’ve sprouted, thin out the extra seedling and use it to fill gaps or create another row.
- Water well after sowing but let the soil dry before watering again to avoid seed rot. If rain is forecast, sow seeds in multi-cell punnets that can be moved undercover.
- Plant in a block formation (not a single row) to ensure good pollination (see ‘How Corn Pollination Works’). Space plants 20-25cm apart in rows 50-60cm apart, with at least three rows in your block.
Feed, Water, Repeat
- As plants grow, increase the depth of watering to encourage the roots to grow deep. Keep the soil consistently moist but not waterlogged.
- Lay down a thick layer of sugar cane mulch to keep roots cool and soil moist.
- When plants reach about 50cm, mound compost and mulch around the base to encourage stronger roots and boost stability.
- Apply extra fertiliser six weeks in, and feed with diluted seaweed extract and fish emulsion weekly for the best results.
Harvest Like a Pro
- The first sign that the cobs are ready is when the silks at the top turn brown. Peel a little of the husk back and pierce a kernel with your thumbnail. If the liquid is milky, it’s ready. If it’s clear, leave it a little longer. If it’s dry, you’ve waited too long!
- Twist and pull downwards to snap off cobs cleanly. Eat them immediately for maximum flavour or store them in the fridge for up to a week.
Pest Patrol
- Look out for corn earworms. This pesky caterpillar feeds on the kernels. To stop it in its tracks, give the tips of developing cobs a gentle squeeze to squash any lurking larvae.
- For added protection, spray Dipel one to two weeks after the silks emerge, and repeat after 10 days.
Preserve Your Harvest
- Freeze it! No need to blanch – just bag and freeze whole cobs, or remove the kernels first. To do this, use a knife to cut away the first row, then rub off the rest with your thumb.
How Corn Pollination Works
Pollen from the male tassels at the top of the plant drifts down to fertilise the female silks on the immature cobs below. Each silk needs to be pollinated to create a kernel – and with 800 kernels per cob, that’s a lot of pollination!
