Spring Onion Growing Guide Crop Rotation Group Allium (Onion family) ● Soil Rich soil with compost dug in. Position Sun or partial shade. Frost tolerant Yes. Feeding Not usually required. Companions Beetroot, Carrot, Strawberry, Tomato, Swiss Chard and Cabbage. Spacing Single Plants: 10cm (3") each way (minimum) Rows: 10cm (3") with 10cm (3") row gap (minimum) Sow and Plant Can be started off early under cover in modules which are then planted out but usually sown direct into position. Our Garden Planner can produce a personalised calendar of when to sow, plant and harvest for your area. Notes Water in dry conditions and keep weed free. Harvesting Harvest as required when they reach a usable size. Planting and Harvesting Calendar < Back to All Plants Pests which Affect Spring Onion Aphids (General) Slug Snail