Fertilizer Schedule for USDA Zone 4
USDA Zone 4 covers areas with minimum winter temperatures of -30°F to -20°F. The growing season runs from May through September, with fertilizer applications from May through September.
Zone 4 Quick Facts
Temperature Range-30°F to -20°F
Average Last FrostMay 10
Average First FrostSeptember 25
Fertilizer SeasonMay to September
Lawn Fertilizer Schedule for Zone 4
Zone 4 lawns receive their first application in May and their last by September. Cool-season grasses (fescue, bluegrass) and warm-season grasses (bermuda, zoysia) follow different NPK ratios at each application.
| Month | Action | NPK |
|---|---|---|
| May | First application after grass begins active growth | 20N 5P 10K N 20% Nitrogen: leaf and stem growth P 5% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK |
| June | Second application for sustained growth | 20N 0P 5K N 20% Nitrogen: leaf and stem growth P 0% Phosphorus: roots and flowers K 5% Potassium: health and disease resistance Learn more about NPK |
| August | Late summer application | 15N 5P 10K N 15% Nitrogen: leaf and stem growth P 5% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK |
| September | Fall winterizer application | 10N 10P 10K N 10% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK |
Garden Fertilizer Schedule for Zone 4
With a last frost around May 10 and first frost around September 25, zone 4 gardens have a 5-month window for fertilizer applications.
| Month | Action | NPK |
|---|---|---|
| May | Prepare beds with compost and starter fertilizer | 5N 10P 5K N 5% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 5% Potassium: health and disease resistance Learn more about NPK |
| June | Side-dress transplants after establishment | 10N 10P 10K N 10% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK |
| July | Feed heavy producers (tomatoes, peppers) | 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 |
| August | Final feeding for fall crops | 10N 10P 10K N 10% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK |
States in Zone 4
11 states contain areas classified as zone 4. Your specific location within a state may fall in a different zone based on elevation and proximity to water.
MinnesotaWisconsinIowaSouth DakotaNebraskaMontanaMaineVermontNew HampshireMichiganNew York