When To Sow: February-September Harvest: June-October
Germination: 3-6 days Full Sun
Direct Seed: Sow into well-prepared beds as soon as the soil can be worked in the spring. The soil should be tilled to a depth of at least 16cm. Radishes prefer well-drained, moderately rich soil and full sun. Avoid soil that is rich in nitrogen, as this will encourage more leafy growth and less energy will go down to the roots. Sow seeds about 1cm deep about 15-20cm apart and cover loosely with soil. Seeds will germinate within one week.
Thin out the seedlings as necessary (you can eat the greens as well as the roots).
Sow successively every 20 days or so from February to September for a constant supply.
Maintenance
Radishes prefer regular watering in dry periods to promote rapid root growth. Avoid fertilizers heavy in nitrogen. Once the seedlings reach 4-5cm tall, keep mulched and well thinned out so the roots have enough space to grow.
Harvesting
Harvest your radishes once a bulb has formed. Spring radishes mature particularly rapidly; so make sure to pull them before they pass their prime and loose their crisp, mild flavour and texture.
Companion Planting
Planting radishes with chervil, cucumber, and squash is mutually beneficial. Avoid planting with cauliflower, hyssop, turnips, or any other plants from the brassica family.