Radishes bolt (fail to develop usable roots) for various reasons. Here are a few: 1. Crowding - Thin the seedlings to at least 1 inch apart when they are a week old. 2. Hot, dry weather - Root development may slow or stop during a dry spell and fail to resume thereafter. Provide plenty of water. 3. Excessive nitrogen - Produces radishes with robust tops and tiny roots. 4. Root maggots - Suspect maggot damage when roots are small, deformed, or one-sided. Use a row cover to keep flies away from the plants. Multiple plantings at two-week intervals during cool growing conditions will improve your chances of producing good radishes. Radish is a cool-season plant and is always ready to bolt to foliage when temperatures begin to be consistently warm. Root crops always do best in loose soil, so consider a raised bed garden if you have heavy soils.

Browse related Faqs by tag: horticulture, vegetable gardens, radishes