Growing Corn in South Australia
Corn is one of those veggies that just tastes so much better if you grow it yourself! You need a fair amount of space to grow corn, because it’s wind pollinated so you need a decent amount of plants to get a high enough pollination rate. It’s a warm season crop which originates in South America and thrives in the hot, dry Southern Australian summers. Supermarkets usually stock sweet corn, while other varieties are grown and dried for maizemeal and popcorn. The maizemeal varieties can also be eaten fresh, but they aren’t as sweet as sweet corn. They are still pretty delicious and definitely worth a try for the more adventurous eaters.
Make sure to plant enough corn plants, 12 plants is probably the smallest you can go, but the fertilization rates will be much better if you have space for 40 – 80 plants. If you plan to save your seeds for next year, you’ll need to have at least 40 plants to maintain genetic variety.
Corn is a particularly heavy feeder. Add lots of compost and well-rotted manure to your soil before planting and dig it through well. Then add some blood and bone, rake it through, water well and let it sit for a week before planting.
Sow your corn once its consistently warm and all danger of frost has passed.
The minimum size for a corn bed is 4 plants by 3 plants. Sow your seeds according to the directions on the packaging. Sow 2 seeds per hole and then thin them out once they're up and established. The thinned plants can be used to fill in any gaps in the bed if germination rates are low. As a fun experiment, you could try the 3 sisters companion planting combination to make the most of the space needed for your corn.
Plant your seedlings out once its consistently warm and all danger of frost has passed.
Corn grows well from seedlings. Plant them into a well-prepared bed, water in and mulch well. Adding a small amount of organic bone meal to each hole will help your corn to develop a strong root system, which will get them through the hot dry weather and produce strong plants.
Corn is wind pollinated, so if your corn patch is on the small side (most urban gardens are), you’ll need to help a bit with pollination. There are various techniques, but an easy and effective way is to use brown paper bags. Keep an eye on the tassels (the male flower right on top of the stalk). Once the tassels turn yellow and start to produce pollen granules, place a bag over them and give them a good shake to collect the pollen. Then, using a paint brush, dust pollen over the female silks found lower on the plant. Repeat this every day for a week for best results. Always remember to wait until the dew on the pollen has dried before you collect it. Pollen doesn’t keep well, so collect a fresh batch each day. If that sounds a bit too labour intensive, you can just pick some tassels each day and dust the silk with them.
Your corn plants may develop side shoots called suckers. In earlier years it was thought that suckers should be removed, but these days it’s widely accepted that it’s better not to remove them. Breaking them off creates wounds which can allow diseases to enter the plant. Suckers have no detrimental effect on the main stalk and larger suckers may even help provide the main stalk with nutrients. If you want to break them off, try to do it while the suckers are still small, so that it has less of an effect on the main stalk.
Corn is a thirsty plant and needs lots of water, especially towards the end of the growing season when the cobs are swelling. The only time you shouldn’t over-water is when you plant your seeds. The seeds can rot easily in the ground, so give them a good soaking when you plant and then wait until they emerge to water again.
Corn is a heavy feeder. Start with a well-prepared bed and then feed again when the flowers appear. A nitrogen-rich feed like manure tea is ideal. Mound compost around your stalks to provide them extra nutrients.
A good thick mulch will make growing corn so much easier! It helps to smother the weeds and keep water in. Lucerne, sugar-cane or pea straw are all good options, but feel free to just use what you have on hand.
When the silks start to die and turn brown, your corn is probably ripe. Stick your nail into one of the kernels, if the liquid that comes out is clear, leave them a little longer. If its milky; its time to harvest.
Simply pull the cobs down till they snap away from the stalks. Heirloom sweetcorn varieties need to be eaten almost immediately. The newer, super sweet varieties can be stored for up to a week before their quality starts to deteriorate.