Sweet Corn Will Grow In Nearly All Soils

Press, Volume CVII, Issue 31523, 10 November 1967, Page 6

Sweet Corn Will Grow In Nearly All Soils

Sweet corn, considered to be a mutation of field corn or maize and of American origin, is becoming increasingly popular and deservedly so. This vegetable, which belongs to the grass family, is high in Vitamin B content and differs from maize in that it contains a higher percentage of sugar and lower level of starch. In the field it can be identified by its smaller stature and greater number of tillers or side shoots which emanate from the base. When dry, the grains of sweet corn have an irregular wrinkled surface due to endospermal shrinkage while those of maize remain comparatively smooth.

J Sweet corn will grow suc'cessfully in nearly all types of soil, from sands to clay, providing it has been well endowed with organic matter. Heavier soils tend to produce more consistent crops which may, however, be a little later in maturing. It is more tolerant to soil acidity than most vegetables grown in the garden and liming is not necessary unless the soil is very acid in which case it is best applied for a previous crop. The addition of superphosphate and possible sulphate of ammonia is usually advantageous and a 1:2:1 mixture of ammonia, phosphorus and potassium at the rate of 2 ounces per square yard can be given. One of the few troubles to beset this crop is germination failure due to organisms which cause seed rotting. For this reason it pays to treat it beforehand with a fungicide such as thiram. Much quality seed is available already treated, indicative by such colours as pink or green coatings on the seed case. Sweet corn does not transplant well and it is usual to sow the seed and then thin the resulting seedlings. Male and female flowers are borne separately, the top one being the male flower and the silk from the embryo cob. the female. To ensure cross pollination therefore block planting should be practised as against single row stands. Inadequate fertilisation may result in fewer cobs, or partly developed and small cobs. They are very frost tender and sowing should not be contemplated until the danger of frosts has passed. Dept of sowing is dependent on soil type and also on available moisture. The heavier and wetter the soil the more shallow should be the sowing, lin to 2in being usual. Seed can be sown 12in to 15in apart in the rows and 2ft to 3ft between them. Germination is usually quite quick under warm conditions and subsequent growth is rapid. In windy conditions plants may require initial support, by drawing the soil up around them. Weeds can be suppressed by spraying the rows with 2.4 D when the plants are 4in

to 6in high but great care is needed when using this hormone as it can be very damaging to other crops. Initially sweet corn does not require a great deal of watering as the roots penetrate deeply into the soil. Once the cobs have set quality can be improved and maturity hastened by regular applications.

It will take from 90 to 120 days from seed sowing before the first cob is ready for picking. The removal of suckers has debatable value, although claims have been made that earlier cropping of superior cobs result when this is done to plants when they are about a foot high.

Sweet corn is one of the few crops which suffers from relatively few pests and even fewer diseases. However during the last few seasons many cobs have been attacked by a caterpillar which destroys the grain. When it is noticed the plants should be given a spraying with carbaryl. The correct stage to pick causes much confusion and it is not unusual to find that one has either harvested immature cobs with pale yellow grains of little or no flavour, or left it so long that an unpalatable hard and starchy product has been served up. The correct picking stage occurs about three weeks after the appearance of silks on the end of the cob. At this stage they will just be turning brown. A good cob should be well filled with firm deep yellow grain which, when pressed with a finger nail, will readily yield a milky juice. Cobs should be carefully removed, by breaking them off with an out and downward motion to avoid damaging the plant Regular picking will extend cropping and provide a more succulent product. The most widely grown varieties appear to be Golden Cross Bantam, the forerunner of hybrid vegetables, and Marcross, an earlier maturing variety. When harvesting has been completed the plants form an excellent source of organic matter. They should be cut down while still green and incorporated in the soil with a little sulphate of ammonia.