Fertilizer for Turnips: NPK Guide and Application Rates
Turnips are a fast-maturing, cool-season root vegetable that produces both edible roots and nutritious greens. Like other root crops, turnips perform best with low nitrogen and higher phosphorus-potassium to encourage root development over excessive leaf growth.
Quick Reference
What NPK Ratio is Best for Turnips?
The recommended NPK ratio for turnips is 5-10-10. The phosphorus-heavy 5-10-10 ratio supports strong root systems and flower/fruit production in turnips.
Turnips NPK needs shift at each growth stage. Low nitrogen to favor root development during the Seedling phase, then not applicable; harvest before flowering once flowering begins.
NPK by Growth Stage for Turnips
| Growth Stage | NPK Ratio | Notes |
|---|---|---|
| Seedling | 5N 10P 10K N 5% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK | Low nitrogen to favor root development |
| Vegetative | 5N 10P 10K N 5% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK | Phosphorus and potassium for root sizing |
| Flowering | 5N 10P 10K N 5% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK | Not applicable; harvest before flowering |
| Fruiting | 0N 10P 10K N 0% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK | Potassium only in the final weeks before harvest |
When Should You Fertilize Turnips?
In zone 3, start fertilizing turnips in May. In zone 10, begin as early as January. Apply every 4 weeks through the growing season.
Which Zones Can Grow Turnips?
Turnips grows in USDA zones 3 through 10, spanning a 8-zone range.
Fertilization Start by Zone
| Zone | Start Month |
|---|---|
| Zone 3 | May |
| Zone 4 | April |
| Zone 5 | April |
| Zone 6 | March |
| Zone 7 | February |
| Zone 8 | February |
| Zone 9 | January |
| Zone 10 | January |
What Are the Best Fertilizer Products for Turnips?
Look for products with an NPK close to 5-10-10. Espoma Garden-tone is the most popular choice among home gardeners for turnips.
- Espoma Garden-tone
- Dr. Earth Root Zone
- Jobe's Organics Vegetable & Tomato
Prices vary by retailer and region. Check current pricing before purchasing.
Container and Raised Bed Adjustments for Turnips
Container turnips need 8+ inch deep pots; a single pre-plant fertilizer application is usually sufficient
Common Fertilizing Mistakes with Turnips
- High nitrogen produces large greens with small, fibrous, bitter roots
- Leaving turnips in the ground too long causes them to become woody and pithy
- Hot weather causes strong, bitter flavor; turnips are a cool-season crop
Tips for Fertilizing Turnips
- Amend soil before planting with compost and a low-nitrogen, phosphorus-potassium fertilizer
- Harvest turnips at 2-3 inch diameter for the sweetest, most tender roots
- Plant a fall crop 8-10 weeks before first frost; frost makes turnips sweeter
Organic Fertilizer Alternatives for Turnips
Sources
Source:Clemson University ExtensionLast updated: