Sweetcorn Growing Guide Crop Rotation Group Miscellaneous ● Soil Warmed, well-drained soil enriched with compost. Position Full sun. Frost tolerant No. Feeding Not usually required. Spacing Single Plants: 35cm (1' 1") each way (minimum) Rows: 30cm (11") with 45cm (1' 5") row gap (minimum) Sow and Plant Sow in pots under cover in mid spring and plant out in early summer. Alternatively sow direct under cloches in late spring. Our Garden Planner can produce a personalised calendar of when to sow, plant and harvest for your area. Notes Plant in blocks of at least 9 plants, all the same variety, to encourage pollination by the wind. Often planted with squash as they like similar conditions. Keep well watered in dry spells. Harvesting Harvest just before eating to get the sweetest taste, when the tassles at the top of the cobs turn brown to black. You can peel back the leaves and check the corn: if they ooze milky sap when pressed with a fingernail then they are ready. Planting and Harvesting Calendar < Back to All Plants Pests which Affect Sweetcorn Aphids (General) Slug Snail Plant Diseases which Affect Sweetcorn Corn Leaf Blight Corn Rust Corn Smut Corn Viruses