Sweet corn is an annual that grows to at least 75 cm - 1.7 m, with male tassels and female ears (cobs) borne on the same plant. Cobs can be golden, white or bicoloured white and yellow. They can be eaten cooked or raw when they are young.
For a full development of this plant are necessary 70-110 frost-free days after planting and temperatures between 16 to 35 Celsius degrees (61-95 F). Sweet corn is a shallow-rooting plant and can grow on a wide range of fertile, well-drained soils with medium nitrogen levels. In warm climates you can grow sweet corn in an open site and in cool climates you can grow early-maturing cultivars in a frost-free, sheltered site.
Sweet corn seeds does not germinate at soil temperatures below 10 Celsius degrees (50 F) so in warm climates sow seeds in spring in situ at 2.5 cm deep and 7 cm apart, and in cool climates sow indoors in modules and plant out seedlings when the soil temperatures reach 13 Celsius degrees (55 F). For optimum pollination you should plant corn in blocks of at least four plants each way, at about 30 cm apart.
For allowing the plants to develop well you should how shallowly when weeding to avoid damaging the roots. Watering should be done in very dry conditions until flowering stars and again later when the grains are swelling.
A corn plant normally produces one or two cobs that should be picked just before required. You can store them in the freezer as the sweet corn freezes well. You will know that the corn is ready for harvesting once the silks have turned brown and the liquid that appear when you press into a kernel with a fingernail is milky. If the liquid is watery then the corn is underripe and if the liquid is doughy the corn is overripe.
