Growing Sweet Corn in the Home Vegetable Garden
Growing Sweet Corn
To be at its best, sweet or sugar corn needs a warmto start in and warm weather to grow and ripen in: if you live in a cold northern area and you are considering growing sweet corn, it is unlikely that the plants will thrive.
Only varieties specially bred for gardens should be used; some of the best are listed below.
The plants at maturity may be anything from 1.5 to 3 m (5-10 ft) high, and this should be taken into account when planning your cropping programme as they may cast shade over neighbouring crops. The plants will grow better if you warm the soil several weeks before sowing. You can do this by laying dear polythene 25-50-gauge sheet over the area to be planted. Sow the seeds through holes punched in the sheet: the seedlings will then emerge through the holes. If you use this method of mulching, bury the edges of the polythene sheet and anchor them with stones.
Sow two seeds 20-40 mm (3/4 – 1-1/2 in) deep at each growing point in late April to mid-May in the south and in late May in warmer northern areas. Alternatively, you can sow indoors – two seeds per 75 mm (3 in) pot – about three weeks earlier in each case, then transplant at the dates indicated. In the garden the plants should be in blocks rather than long rows in order to help pollination. The plants should be spaced 250 mm (10 in) apart, with 400 mm (16 in) between the block rows, with the growing points staggered in alternate rows; this gives an effective 350 mm (14 in) between each plant and its neighbours in all directions. Thin to the stronger plant at each point. As the plants grow, give them extra support by drawing up soil around the base of the stem.
The site should be sunny and protected against winds. The soil should be neither very light nor heavy; it must drain well, and it should have been thoroughly dug in the winter, with compost incorporated for a previous crop. Add a scattering of general fertiliser before sowing. Keep the soil moist in dry weather, especially after the plants flower. Pinch out any side shoots that appear.
Unless the weather is exceptionally warm and the plants very vigorous, do not allow more than three or perhaps four cobs to grow on each plant. When the male tassels at the top of the plant are ready they shed pollen onto the femalebelow. You can help this shedding process by tapping the stems of the plants. Eventually the green sheath covering each cob swells as the fruit inside develops. Test for ripeness by peeling away a small piece of the sheath and pressing two or three of the grains with the edge of your thumb nail. If the grain is ripe, a milky juice will spurt out. If the juice is dear and watery, the corn is not yet ripe; if it is very thick or doughy it is over-ripe and will be tough.
Harvest the cobs when they are ready. They should be cooked and eaten as soon as possible as they will dry out quickly.
Earth up the sweet corn plants a little when they are about 1 ft. high and they will produce stronger roots, which will give the plants more support. During the summer, the plants may need three-quarters of an hour of artificial rain or a good watering with hose or can once a week. Mulch the soil all over the plot to conserve as much moisture as possible.
The cobs should be ready for harvesting about three or four weeks after flowering finishes. The tassels will turn brown and begin to lose their silkiness. Pull back the protecting green sheath and press one or two of the grains with the thumbnail. The contents should spurt out with the consistency of thick cream.
If the cobs are pulled too early the grains will be watery; if pulled late, the grains will be hard, dry and unpalatable.
Early Golden Market, early, yellow-golden grains.
Golden Bantam, tender yellow grains. Very sweet and fairly hardy.
Golden Glory, cobs 8 in. long, with M rows of grains. Matures early and is a heavy cropper.
John Innes Hybrid, an early maturing, sweet variety. Grows up to 5 ft. tall.
All the following are early, and so have a better chance of ripening in our climate; all are sweet, some slightly more so than others: ‘Aztec’, F1; ‘Earliglo’; ‘Extra Early Sweet’, Fr; ‘Kelvedon Kandy Cob’, Fl; ‘Kelvedon Sweetheart’, F1
Site: Sunny, sheltered
Soil: Good, well-drained
Sow: April to mid-May in south; late May in north