Growing popcorn

corn.jpgFoods made from genetically engineered (GE) crops, also known as genetically modified (GM) foods, are not required to be labelled in the United States, and Australian consumers of imported corn products could unknowingly be eating these foods. Labelling rules for GE/GM foods set by Food Standards Australia New Zealand (FSANZ) fail to protect consumers as they allow many exceptions to labelling of GE/GM foods and ingredients, and rely heavily on the honesty of producers and processors to inform the public of the genetically engineered content of the food they buy. There is no post-marketing assessment of foods to ensure compliance with GE/GM labelling regulations.
If your family is fond of eating popcorn, and you wish to avoid GM foods, why not grow your own popcorn this summer.

Update – 16/11/2013
The first step is to buy popcorn seed, which is becoming extremely difficult to find. Gardeners in QLD, NSW, VIC and the NT can order organically-certified seed from:
Green Harvest –  ‘Popcorn’, although the variety being sold this year is a hybrid which means that you won’t be able to save some seed for next year’s crop. It appears that ‘Golf Ball’, ‘Ontos’, ‘Ruby’, ‘Blue Mini’ and ‘Strawberry Mini’ have already disappeared from the market.
Popcorn is made from a particular ancient variety of corn whose kernels (seeds) contain air pockets. When the dried kernels are heated, the air in the kernels expands and the seed “pops” open. Plants that produce popcorn may have several stems and carry multiple small cobs, instead of the usual two large cobs per plant of many other corn varieties.
Popcorn is grown in the same way as sweet corn, as it is also a heavy feeder. It needs a sunny position and well-drained soil that has had plenty of organic matter added in the form of compost or well-rotted manures, plus an application of complete organic fertiliser. All varieties of corn do well if grown after a green manure crop – a point to remember for next year. Because corn relies on wind drift for pollination, small quantities of corn are best grown in a block rather than rows. If you are growing other varieties of corn, allow at least a month between sowing popcorn and the other varieties because they can cross-pollinate.

Sowing seed:
Corn requires a soil temperature of 20° C for germination. Popcorn can be sown from August North of Rockhampton, and from September in other warm areas. Other areas can begin sowing in October. Popcorn takes a little under 4 months to reach maturity.
Seed is sown directly into a mulched bed. Space planting holes 40-45 cm apart, and sow two seeds, 3 cm deep, in each hole. Traditionally, popcorn is sown during First Quarter moon phase.
When seedlings have developed their second set of leaves, thin them to the strongest seedling at each position, and give the seedlings a drink of manure tea. When plants are knee high, hill them up about 15 cm encourage extra roots to form, and to make the plants more stable in windy conditions. Corn requires regular irrigation until cobs mature, and it more likely to attract corn earworm if water is in short supply.

Pollination:
Corn plants produce separate male and female flowers. The male flowers that produce pollen are shaped like ears of wheat at the top of the plant. Another drink of manure tea, and a drink of seaweed tea can be applied when the male flowers start to form.
The female “flowers” are the green silk tassels that protrude from the cob sheath. Each strand of the tassel is attached to a single kernel on the cob and poor pollination occurs when wind is absent and pollen only falls onto one side of the tassel. In still conditions, you may have to flop the tassels around, or transfer pollen with a dry paintbrush to ensure that all the silk strands are pollinated.

Harvesting popcorn:
Popcorn cobs remain on the plants past the harvesting stage for sweet corn, to allow the seeds to fully mature. As soon as tassels have browned, the plants should be netted, as birds know exactly when corn is perfect for eating. When the husk, or sheath, of the cobs has begun to dry and is changing to a pale cream colour, the corn is close to maturity. If weather is fine, cobs can be left on the plants until the sheaths are completely dry, or they can be brought indoors at this point to complete drying. We leave them on racks indoors for several days, then carefully peel back the husks, thread wool or string through the turned-back husks, tie the string to form a loop, and hang the cobs from a hook until the seeds are completely dry about 14 days after the husks have dried. Kernels can be left on the cob or shucked by rubbing two cobs together over a large bowl. It is recommended that the kernels be transferred to a sealed plastic container and frozen for two days to kill any weevil eggs that made have been laid in the seeds. After freezing, transfer the popcorn to a screw-top jar, and pop as required.