Corn (maize) is one of the most rewarding crops for the Australian home gardener. There is nothing quite like the flavor of "super sweet" corn harvested and eaten within minutes, as the sugars begin converting to starch the moment the cob is picked. Given Australia's diverse climates, success with corn depends on timing, soil preparation, and understanding the unique pollination needs of this tall, architectural grass.

Understanding the Australian Seasons

Corn is a frost-tender, warm-season crop. It requires a soil temperature of at least 16°C for germination, though 20°C to 30°C is the "sweet spot" for rapid growth.

• Tropical/Sub-tropical (QLD/NT/Northern NSW): Corn can be grown almost year-round, though the best results usually occur from August to March to avoid the peak humidity and pest pressure of mid-summer.
• Temperate (NSW/VIC/SA/WA): Plant from October to January. In cooler regions, starting seeds in biodegradable pots indoors can give you a head start on the season.
• Arid/Inland: Planting should occur in early spring or late summer to avoid the extreme heat of January, which can dry out the tassels and prevent pollination.

Soil Preparation: The Heavy Feeder

Corn is a "heavy feeder," meaning it requires significant nutrients to produce those juicy kernels. It thrives in well-drained soil with a pH between 6.0 and 7.0.

1. Enrichment: Two weeks before planting, dig in plenty of well-rotted manure or compost. Corn particularly loves nitrogen.
2. Structure: Ensure the soil is friable (crumbly). If you have heavy clay, consider raised beds to improve drainage.
3. Position: Choose the sunniest spot in your garden. Corn needs at least 6–8 hours of direct sunlight daily.

The Secret to Success: Block Planting

The most common mistake beginners make is planting corn in a single long row. Corn is wind-pollinated. Pollen falls from the "tassels" (the flowers at the top) onto the "silks" (the threads poking out of the ears).

To ensure every kernel is filled, plant corn in blocks rather than a thin line. This creates a dense cloud of pollen that is much more likely to hit the target. Space plants about 30cm apart with 50cm between rows.

Care and Maintenance

Watering

Corn has a shallow root system and high water requirements, especially once the cobs begin to form. Mulch heavily with straw or lucerne to retain moisture. If the leaves start to curl or "roll up," the plant is under water stress.

Fertilizing

Once the plants are about knee-high, "side-dress" them with a high-nitrogen fertilizer or a liquid seaweed feed. This gives them the energy boost needed for the final stretch of growth.

Hilling

As the plants grow tall, they can become top-heavy. Draw soil up around the base of the stems (hilling). This encourages "prop roots" to grow, which anchor the plant against the strong winds common in Australian summers.

Common Pests and Problems

The primary enemy of Australian corn is the Heliothis moth (Corn Earworm). The moth lays eggs on the silks, and the larvae burrow into the tip of the cob.

• The Tip: You can deter them by applying a few drops of vegetable oil or a Neem-based spray to the silks once they have turned brown.
• Birds: Cockatoos and crows love corn. You may need to use bird netting or place paper bags over the cobs once pollination is complete.

Harvesting: The "Milk" Test

Knowing when to pick is an art. Usually, corn is ready 18–24 days after the silks first appear.

1. The Look: The silks should be dark brown and withered, and the cob should feel plump and rounded at the tip.
2. The Test: Peel back a small section of the husk and pierce a kernel with your fingernail.
• If the liquid is clear, it’s too early.
• If it’s milky, it’s perfect.
• If it’s thick/pasty, it’s overripe and will be starchy.

Popular Australian Varieties

• Balinese: A hardy, open-pollinated variety that handles heat well.
• Bicolour: Popular for its mix of white and yellow kernels and intense sweetness.
• Golden Bantam: A classic heirloom variety with excellent traditional corn flavour.

Growing corn is a rite of passage for many Australian gardeners. While it takes up a bit of space, the architectural beauty of the stalks and the incomparable taste of a sun-warmed cob make it well worth the effort.