|Zea mays subsp. var. convar. saccharata var. rugosa||Sweet corn|
Sweet corn (Zea mays convar. saccharata var. rugosa; also called Indian corn, sugar corn, and pole corn) is a variety of maize with a high sugar content and prepared as a vegetable. Unlike field corn varieties, which are harvested when the kernels are dry and mature (dent stage), sweet corn is picked when immature (milk stage). Since the process of maturation involves converting sugar into starch, sweet corn stores poorly and must be eaten fresh, canned, or frozen before the kernels become tough and starchy.
Annual growing to 2m at a fast rate.pf
It is hardy to zone 9 and is frost tender. It is in flower from July to October, and the seeds ripen from September to October. The flowers are monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and are pollinated by Wind.pf
The plant prefers light (sandy), medium (loamy) and heavy (clay) soils and requires well-drained soil. The plant prefers acid and neutral soils. It cannot grow in the shade. It requires moist soil.pf
Requires a warm position a well drained soil and ample moisture in the growing season[16, 33]. Prefers a pH in the range 5.5 to 6.8. Requires a rich soil if it is to do well. Corn is widely cultivated for its edible seed, especially in tropical and warm temperate zones of the world, there are many named varieties. Unfortunately, the plant is not frost tolerant and so needs to be started off under glass in Britain if a reasonable crop is to be grown. There are five main types:- Sweetcorn is of fairly recent development. It has very sweet, soft-skinned grains that can be eaten raw or cooked before they are fully ripe. Cultivars have been developed that can produce a worthwhile crop even in the more northerly latitudes of Britain if a suitable warm sunny sheltered site is chosen[238, K. Popcorn is a primitive form with hard-skinned grains. When roasted, these grains 'explode' to form the popular snack 'popcorn'. Waxy corn is used mainly in the Far East. It has a tapioca-like starch. Flint corn, which shrinks on drying, can have white, yellow, purple, red or blue-black grains. It is not so sweet and also takes longer to mature so is a problematic crop in Britain. There are many other uses for this plant as detailed below. Dent corn has mostly white to yellow grains. This and Flint corn are widely grown for oils, cornflour, cereals and silage crops. Corn grows well with early potatoes, legumes, dill, cucurbits and sunflowers[18, 20, 201], it dislikes growing with tomatoes.pf
Seed - sow April in individual pots in a greenhouse. Grow on quickly and plant out after the last expected frosts. A direct outdoor sowing, especially of some of the less sweet varieties, can be tried in May.pf
Pests and diseases
There are currently hundreds of varieties, with more constantly being developed.
Open pollinated (non-hybrid) corn has largely been replaced in the commercial market by sweeter, earlier hybrids, which also have the advantage of maintaining their sweet flavor longer. Su varieties are best when cooked within 30 minutes of harvest. Despite their short storage life, many open pollinated varieties such as Golden Bantam remain popular for home gardeners and specialty markets, or are marketed as heirloom seeds. Although less sweet, they are often described as more tender and flavorful than hybrid varieties.
Sweet corn production in the 20th century was influenced by the following key developments:
- hybridization allowed for more uniform maturity, improved quality and disease resistance
- identification of the separate gene mutations responsible for sweetness in corn and the ability to breed varieties based on these characteristics:
- su (normal sugary)
- se (sugary enhanced, originally called Everlasting Heritage)
- sh2 (shrunken-2)
Modern breeding methods have also introduced varieties incorporating multiple gene types:
- sy (for synergistic) adds the sh2 gene to some kernels (usually 25%) on the same cob as a se base (either homozygous or heterozygous)
- augmented sh2 adds the se and su gene to a sh2 parent
Often seed producers of the sy and augmented sh2 types will use brand names or trademarks to distinguish these varieties instead of mentioning the genetics behind them. Generally these brands or trademarks will offer a choice of white, bi-color and yellow varieties which otherwise have very similar characteristics.
- ↑ Sweet Corn—Mutant or historic species?, Economic Botany, volume 5, issue 3, page 302
- ↑ http://www.news.uiuc.edu/II/03/0807/sweetcorn.html
- Plants for a Future - creative commons text incorporated