Radish Container Soil Mix
Raphanus sativus
Loose, lean, deeply-loosened mix so roots size up smooth and round without forking.
- Container:
- 1-5 gal (≥6" depth)
- pH:
- 6–7
- Sun:
- 6–8 hr
- Light:
- Full sun (6+ hours), tolerates light shade
Components
Percentages by volume. Quantities scaled for a 2-gallon container (US units).
| Component | % | Amount |
|---|---|---|
| Quality potting mix Base structure, initial nutrients | 50% | 4 qt |
| Coco coir (low-EC, buffered) CEC, moisture buffering | 20% | 1.5 qt |
| Coarse sand Mimics native sandy loam, drainage | 15% | 1 qt |
| Perlite Drainage, aeration | 10% | 3.25 cup |
| Aged compost Microbial diversity | 5% | 1.5 cup |
Per-container amendments
Scaled linearly to your container size. Apply at transplant or as side-dress per the notes on each line.
- Balanced organic fertilizer (4-4-4 / 5-5-5) Keep light — excess N grows leaves at the expense of roots.1–2 tbsp
- Kelp meal Provides potassium for root sizing.1 tsp
Growing notes
- Radishes are a fast root crop — sow direct, thin early to 1-2" spacing, harvest in 25-30 days for round types.
- Keep compost MODEST: too much nitrogen produces big tops and small/forked roots.
- Loose, stone-free mix is critical — anything compacted or clumpy forks the root.
- Round types need 6" depth; daikon/long types want 10-12".
- Even moisture prevents cracking and woody, pithy roots; dry/wet cycles ruin texture.
Want to scale this to a different container size, save it to a plot plant, or track applied dates? Open it in the interactive calculator.
References
- Growing radishes in home gardens — University of Minnesota Extension . University of Minnesota Extension
- Radishes — UF/IFAS Gardening Solutions . University of Florida IFAS Extension
- Radish — Oregon State University - Oregon Vegetables . Oregon State University Extension