Fertilizer for Peas: NPK Guide and Application Rates
Peas, like beans, are nitrogen-fixing legumes that partner with Rhizobium bacteria to produce their own nitrogen. Supplemental nitrogen fertilizer is counterproductive and can actually inhibit the nitrogen-fixing process. Focus on phosphorus and potassium instead.
Quick Reference
What NPK Ratio is Best for Peas?
The recommended NPK ratio for peas is 5-10-10. The phosphorus-heavy 5-10-10 ratio supports strong root systems and flower/fruit production in peas.
Peas NPK needs shift at each growth stage. Low nitrogen starter; peas fix their own nitrogen during the Seedling phase, then no supplemental nitrogen needed during bloom once flowering begins.
NPK by Growth Stage for Peas
| 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 starter; peas fix their own nitrogen |
| 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 support vine growth |
| Flowering | 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 | No supplemental nitrogen needed during bloom |
| 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 | P-K only for pod fill |
When Should You Fertilize Peas?
In zone 3, start fertilizing peas in May. In zone 10, begin as early as January. Apply every 6 weeks through the growing season.
Which Zones Can Grow Peas?
Peas 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 Peas?
Look for products with an NPK close to 5-10-10. Espoma Garden-tone is the most popular choice among home gardeners for peas.
- Espoma Garden-tone
- Dr. Earth Vegetable Garden Fertilizer
- Down to Earth Bio-Fish
Prices vary by retailer and region. Check current pricing before purchasing.
Container and Raised Bed Adjustments for Peas
Container peas need a trellis and light feeding every 3-4 weeks with low-nitrogen liquid fertilizer
Common Fertilizing Mistakes with Peas
- Adding nitrogen fertilizer inhibits rhizobial nitrogen fixation and wastes money
- Planting too late in warm soil causes poor germination and stunted plants
- Failing to provide a trellis for climbing varieties reduces yield and promotes disease
Tips for Fertilizing Peas
- Inoculate seeds with pea/vetch-specific Rhizobium inoculant before planting in new soil
- Apply phosphorus and potassium at planting; skip the nitrogen entirely
- Plant peas as early in spring as soil can be worked; they prefer cool weather
Organic Fertilizer Alternatives for Peas
Sources
Source:Clemson University ExtensionLast updated: