How to grow sweetcorn – Which?

The sheer pleasure of eating extremely flavored, creamy, home-grown sweet grains makes it an indispensable summer crop for many vegetable gardeners.

How to grow seedlings: month after month

The best varieties of sweet corn

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How we test sweeteners

In early May, we saw 14 species of sweet corn inside rooting machines. We planted them outdoors at our trial price in north Gloucestershire in early June. They were planted in blocks of 72 plants at 35 cm intervals, using soil cover to retain moisture and control weeds. They were protected against gear damage and deer by electric fencing. We harvested grain from the 20 plants in the center of the property as they matured. We measured and weighed the coals, checked how even they were and how well they were filled with grains, and then measured how sweet the grains were for up to a week after harvest. All bottles were tasted by trained tasters. These experts can identify and evaluate unique taste factors such as the intensity of the sweetness and detect subtle differences in flavors. They also noticed how tasty the coals looked when they were raw and boiled and looked for shiny, thick, the same size in small rows.

When to sow

Sow in 7 cm deep pots or root trainer in April to reduce root disruption later. Provide a minimum temperature of 15 ° C to encourage germination and good growth. Cure the plants for planting after the risk of frost has passed.

Take care of your plants


Choose a sheltered spot in full sun and dig in compost in the garden or soil nutrient.

Wait until the risk of frost has passed in mid and late May. Planted in blocks with at least 12 plants to ensure good pollination in the wind. However, keep different types separate to avoid cross-pollination, which can affect the quality of the grain. Plants at 35 cm intervals will usually produce a good top on each plant. Plant further apart (45 cm) if you also want to try smaller second cobwebs.

to water

Liquid when charcoal is formed and silk appears on the ears. At this point, it is also a good idea to shake the sweet potato stalks on a quiet evening. This ensures that the pollen released by the male flowers on top of the plant reaches the cornea below all the female sides and helps each seed to mature.

How and when to harvest

Harvest in: August to September

The coals should be ripe when all the silk is brown and shrunk. Pull the shell back and the grains should be plump and yellow. Slide the nail into the weight – the liquid that comes out should be milky when the flask is ready to eat.

Common growth problems


Sweet grains can suffer from dirt, a disease that causes black mold on the coals to erupt. It is not common, but destroy the cultivated effect and cultivate grain elsewhere next year

Read more about sweet corn.


Those who have sweet teeth like rats, squirrels and crows love ripe grains. Stingrays and deer can also see when the grain is ripe and therefore we had to protect our experimental crop with an electric fence.

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