Data · Source-cited · 20 crops
NPK Fertilizer Rates by Vegetable Crop
Typical pre-plant N, P₂O₅ and K₂O rates for common home-garden vegetables, aggregated from US cooperative extension publications. A real soil test always overrides these defaults — we list them as a starting point when a test is unavailable.
How to read this table
- N, P₂O₅, K₂O are the nutrients on a fertilizer bag label — a 10-10-10 bag is 10% of each by weight.
- Rates are given per 1000 ft² (≈ a 25 × 40 ft garden). To convert to g per m², multiply by 4.88.
- Heavy feeders (tomato, corn, brassicas) need a second side-dress mid-season; light feeders (legumes, carrot) do not.
- These are total season rates — split them per the Timing column.
- Always soil-test first. These rates assume moderate-fertility soil; very low-P or very high-K soils need adjustment.
Season rates, by crop
| Crop | Feeder | N lb/1000 ft² · g/m² | P₂O₅ lb/1000 ft² · g/m² | K₂O lb/1000 ft² · g/m² | Timing | Source |
|---|---|---|---|---|---|---|
| Tomato | Heavy | 3–414.6–19.5 | 2–39.8–14.6 | 3–414.6–19.5 | ½ pre-plant, ½ side-dress at fruit set | UMass-VegGuide |
| Pepper | Moderate | 2–39.8–14.6 | 2–39.8–14.6 | 2–39.8–14.6 | ⅔ pre-plant, ⅓ side-dress 4 weeks after set | UMass-VegGuide |
| Eggplant | Moderate | 2–39.8–14.6 | 2–39.8–14.6 | 2–39.8–14.6 | ½ pre-plant, ½ side-dress at first bloom | UMass-VegGuide |
| Sweet Corn | Heavy | 3–414.6–19.5 | 29.8 | 2–39.8–14.6 | ½ pre-plant, ½ at knee-high (V6–V8) | PSU-AG-32 |
| Cucumber | Moderate | 2–39.8–14.6 | 29.8 | 29.8 | ⅔ pre-plant, ⅓ at vining | Rutgers-FS129 |
| Summer Squash | Moderate | 2–39.8–14.6 | 29.8 | 29.8 | ⅔ pre-plant, ⅓ at first bloom | Rutgers-FS129 |
| Winter Squash | Moderate | 2–39.8–14.6 | 29.8 | 2–39.8–14.6 | ⅔ pre-plant, ⅓ at vining | UGA-C1027 |
| Watermelon | Moderate | 2–39.8–14.6 | 29.8 | 2–39.8–14.6 | ½ pre-plant, split side-dress through vining | UGA-C1027 |
| Cabbage | Heavy | 3–414.6–19.5 | 29.8 | 29.8 | ⅔ pre-plant, ⅓ 3–4 weeks after transplant | UMaine-2276 |
| Broccoli | Heavy | 3–414.6–19.5 | 29.8 | 29.8 | ⅔ pre-plant, ⅓ 3–4 weeks after transplant | UMaine-2276 |
| Cauliflower | Heavy | 3–414.6–19.5 | 29.8 | 29.8 | ⅔ pre-plant, ⅓ at head formation | UMaine-2276 |
| Lettuce | Light | 1–24.9–9.8 | 1–24.9–9.8 | 1–24.9–9.8 | All pre-plant; one top-dress if leaves pale | Cornell-HomeVeg |
| Spinach | Moderate | 2–39.8–14.6 | 1–24.9–9.8 | 1–24.9–9.8 | All pre-plant; top-dress at 4 true leaves | Cornell-HomeVeg |
| Kale / Chard | Moderate | 2–39.8–14.6 | 1–24.9–9.8 | 1–24.9–9.8 | Pre-plant; side-dress every 4 weeks of harvest | Cornell-HomeVeg |
| Carrot | Light | 1–24.9–9.8 | 29.8 | 2–39.8–14.6 | All pre-plant; avoid excess N (forked roots) | UMN-VegN |
| Beet | Light | 1–24.9–9.8 | 29.8 | 29.8 | All pre-plant | UMN-VegN |
| Onion / Garlic | Moderate | 2–39.8–14.6 | 29.8 | 29.8 | ½ pre-plant, ½ in split side-dresses through bulking | UGA-C1027 |
| Potato | Moderate | 2–39.8–14.6 | 29.8 | 3–414.6–19.5 | ½ pre-plant, ½ at hilling | UMaine-2276 |
| Bean (bush/pole) | Light | 0.5–12.4–4.9 | 1–24.9–9.8 | 1–24.9–9.8 | All pre-plant; avoid excess N (reduces pods) | Rutgers-FS129 |
| Pea | Light | 0.5–12.4–4.9 | 1–24.9–9.8 | 1–24.9–9.8 | All pre-plant; inoculate seed with rhizobia | Rutgers-FS129 |
Rates shown are mid-range of values typically published across state cooperative extensions for home gardens on moderate-fertility soil. Individual state recommendations vary by ±25% depending on regional soil types and climate.
Converting a rate to bag weight
The table tells you pounds of nutrient, not pounds of fertilizer. To translate, divide the nutrient rate by the bag’s analysis percentage:
Formula
bag_lbs = (nutrient_lbs_per_1000_sqft × area_sqft ÷ 1000) ÷ (bag_analysis_% ÷ 100)
Worked example
A 200 ft² tomato bed, targeting 3 lb N / 1000 ft² pre-plant, using 10-10-10:
(3 × 200 ÷ 1000) ÷ (10 ÷ 100) = 6 lb of 10-10-10
Our Fertilizer NPK Calculator does this math for you, including split applications and non-10-10-10 bags like urea (46-0-0) or 5-10-15.
When these numbers are wrong
- You have a soil test. Always follow the test’s P and K recommendations — this table is only a starting point for unknown soils.
- Very acidic or very alkaline soil. Nutrient availability drops sharply outside pH 6.0–7.0. Fix pH first with our Soil pH Calculator, then fertilize.
- Heavy organic matter (≥ 5%). Rich, well-composted soil supplies substantial N through mineralization — reduce synthetic N by 25–50%.
- High-tunnel or container growing. Confined root zones and frequent irrigation leach nutrients faster; split more heavily and feed more often.
- Organic fertilizers (compost, manure, blood meal). Nutrient release is slower and temperature-dependent. A 3 lb N / 1000 ft² target from compost may require 20–30 lb of finished compost per 100 ft² — estimate with our Compost Calculator.
Sources
The rates above are aggregated from the following cooperative extension publications. Where sources disagree, we list the mid-range; where they agree closely, we list the common value.
- New England Vegetable Management Guide — Nutrient ManagementUMass Extension / New England Cooperative Extensions · cited as UMass-VegGuide
- Sweet Corn — Soil Fertility (AG-32)Penn State Extension · cited as PSU-AG-32
- Fertilizing the Home Vegetable Garden (FS129)Rutgers NJAES Cooperative Extension · cited as Rutgers-FS129
- Home Garden Fertilization (Circular 1027)UGA Cooperative Extension · cited as UGA-C1027
- Maine Home Garden News — Fertilizing Vegetables (Bulletin 2276)University of Maine Cooperative Extension · cited as UMaine-2276
- Home Vegetable Gardening — Soil & FertilityCornell Cooperative Extension · cited as Cornell-HomeVeg
- Nutrient Management for Commercial Vegetable Crops — Home-garden EquivalentsUniversity of Minnesota Extension · cited as UMN-VegN