How long do radishes take to fully grow?
Written by
Julia Anderson
Reviewed by
Prof. Martin Thorne, Ph.D.How long does it take radishes to grow? It depends mostly on the variety and conditions. The summer types, such as Cherry Belle, mature the quickest, in 22-35 days, while the winter Daikon may take 60-70 days. Soil temperature is crucial; radishes grow more quickly at temperatures between 50°F and 70°F. (10-21C). I watch the soil thermometer when the soil is being prepared for planting.
Maturation speed is dependent on essentially the same factors (apart from variety). Consistent moisture prevents delay due to stress. Loose to loose soil allows for rapid growth without obstruction. Full sun provides maximum photosynthesis. My garden journal indicates that radishes in my raised beds mature on average 15% sooner than radishes sown in compacted soil. Containers often yield the same speed effectively.
Temperature Effects
- Optimal range: 50-70°F (10-21°C) for peak metabolism
- Below 40°F (4°C): Germination halts, growth pauses
- Above 85°F (29°C): Bolting risk increases dramatically
- Frost impact: Winter varieties sweeten, summer types die
Soil Conditions
- Loose texture: Sandy loam allows 25% faster growth
- Compacted soil: Adds 10-15 days to maturity
- pH balance: Maintain 6.0-7.0 for nutrient uptake
- Nutrient density: Excess nitrogen delays root formation
Speed up growth of seedlings: soak seeds overnight before sowing. Put down black plastic mulch early to warm the soil. Use an even balanced liquid fertilizer at 14 days after sowing. My fastest crop matured in 19 days. Successive crops may be sown every 10 days.
Discover the signs of maturity, and you cannot fail to gather your radishes at the perfect time. Summer sorts push slightly above the ground when ready; the shoulders of the winter variety are visible. To test their dimensions, you can brush away the soil from the tops of the roots. I take mine when firm to the touch, but not hard. The moment that the gathering can be delayed without deterioration, wrapped radishes become woody in taste, especially in hot weather.
Slow growth troubleshooting.If your seedlings aren't growing, ensure the soil isn't too dry or compacted. They may also be overcrowded, with thin seedlings spaced too closely together as soon as they are large enough. If that doesn't help, test the pH. Potted radishes require daily watering. My garden perked up and got back on track by giving it a dose of compost tea every 10 days.
Read the full article: How to Grow Radishes: Foolproof Guide
