Radishes can be grown all season but they’re easiest when sown March/April and again August through October. Optimal soil temperature: 18-24°C (65-75°F). Seeds should sprout in 5-7 days. Summer production of radish may not be as uniform. Sow seeds 1⁄2” apart and 1⁄4” deep in rows 12-18” apart. Thin to 6-12 plants per 12”. Make successive sowings every 5-7 days to keep a constant supply of fresh radish all season.
Requires full sun and pH of 6.0-7.0. Extremely light feeders; no special soil preparation is required. Sufficient water is essential as the faster the radish, the better the flavour. Plant radish in rows with slow germinating seeds like carrots, parsnip and beets to help break the soil and aid in the germination of the slower seeds.
Harvest as soon as roots reach a desired size, 20-25 days or when the radishes are the size of a large marble. Every part of the radish is edible. If you leave some of your radishes to go to seed, you’ll find the pods before seed set are tender and juicy with a wonderfully sharp flavour that is excellent in stir-fries and soups. If you harvest the seeds before they dry, they have a taste and texture reminiscent of caviar. Imagine the fresh seeds lightly sautéed with garlic and thyme on a bed of radish leaves.
Pests & Diseases:
Flea beetles, small, shiny, hopping insects that leave small holes in the leaves. Avoid planting too early; use row covers or Rotenone dust to control insects. Also, planting with taller growing companions will help to hide the plants from insects.
Lettuce, bean, beet, carrot, parsnip, pea, spinach. Radish improves the flavour of lettuce.