How to Grow Corn

Corn is classed as a leaf crop and a warm season crop, it's basically a grass like its fellow rice and wheat. It is a heavy feeder and can be planted with other leaf crops or, as I do, in with the Cucurbits (pumpkins, melons etc). When growing corn, you can either grow it from seed, direct sown, raise it from seed in a glasshouse and transplant it or grow it from seedlings. I grow my corn at the back of my pumpkin bed, planting both at the same time. By the time the pumpkin plants start to spread, the corn plants have grown above and by the time the corn have finished, the pumpkin plants can use the spent corn stalks as support. It is a good idea to successive plant (plant a batch, wait a few weeks, then plant more etc) as each plant generally only produces two or three cobs. 


Corn is fertilised by wind, the pollen from the male tassle that develops at the top, dropping down to the female ears where the corn cobs grow. The plants are best grown in "blocks" rather than a long row as this helps improve pollination. I always plant mine no more that 20cm apart. This creates a dense patch, so make sure they aren't completely shading other plants in the same bed. Some wind/air movement is necessary for the pollination, but, on the other had, exposure to gale force winds will result in broken stems, so some protection may be necessary. 


If transplanting seedlings, make sure you plant the seedlings deeper than they have grown in the punnet. Corn plants throw out side aerial roots from the first "joint" of the stem for additional support. As the plants mature and these roots shoot, I build up the mulch, laced with fertliser around the stems. This gives them a good boost as the corn ears form. At this stage, ensure that the plants are regularly watered to ensure nice healthy cobs. 


Although many people say the ears are picked when the tassle "hairs" turn brown, but, in my experience this is too early. Make a weekly check after this point, peeling back some of the end cob leaves gently to expose the corn. Squash a kernel and see if the sap is milky. If it is, the cob is ready.


When the cobs are ripe, pick them and eat them fresh with butter and salt or, straight in the freezer! No peeling, no part boiling!

Growing Conditions


Position: Full Sun, protected from strong winds


Plant: Sow direct in Spring when soil temperatures have increased or in punnets in a greenhouse and transplant at around 10-15cms tall.


Frost Tolerant: No. Heat tolerant:  Yes


Feeding: Side dress with blood and bone and a manure with mulch when the aerial roots appear.


Planting group: Leaf crop - can be grown with cucurbit crops.


Pests: Birds, snails and slugs as seedlings, then corn ear worm and aphids as cobs develop.


Harvesting: When the tassles of the cobs turn brown to black, partially peel back the leaves and check the corn. Squash a kernel and it oozes milky sap, the cob is ready. Eat the same day, or see the preserves page.