Seed Needed
0.5 lbs
Cost
$2
N Fixed
2.3 lbs
= 0.023 acres
Inputs
Result
Crimson clover at 0.5 lb/1000sqft costs just $2.25 in seed and fixes about 2.3 lbs of nitrogen, saving roughly $1.84 in fertilizer.
Inputs
Result
Winter rye needs more seed (2.5 lb/1000sqft) but at $1.20/lb it is still affordable. It overwinters and provides excellent weed suppression.
Seeding rates vary by species. Crimson clover needs 0.5 lbs per 1,000 sq ft, winter rye needs 2.5 lbs, and buckwheat needs 1.5 lbs. A typical 1,000 sq ft garden bed costs $1-$5 in seed depending on species.
| Crop | Rate/1000sqft | Cost/1000sqft |
|---|---|---|
| Crimson Clover | 0.5 lb | $2.25 |
| Winter Rye | 2.5 lb | $3.00 |
| Buckwheat | 1.5 lb | $3.00 |
| Oats | 2.0 lb | $1.60 |
Hairy vetch fixes the most nitrogen at 120 lbs per acre, followed by white clover at 130 lbs per acre (permanent), red clover at 110 lbs, and crimson clover at 100 lbs. Non-legume crops like rye and oats fix zero nitrogen but provide other benefits.
| Legume | N Fixed/Acre | Fertilizer Equiv. (10-10-10) |
|---|---|---|
| White Clover | 130 lb | 26 bags |
| Hairy Vetch | 120 lb | 24 bags |
| Red Clover | 110 lb | 22 bags |
| Crimson Clover | 100 lb | 20 bags |
Winterkill crops (buckwheat, oats, daikon radish, field peas) die in freezing temperatures and form a no-till mulch mat. Overwintering crops (winter rye, crimson clover, hairy vetch) survive winter and resume growing in spring, requiring mowing or tilling before your garden planting.
| Behavior | Pros | Cons |
|---|---|---|
| Winterkill | No spring work, no-till ready | Less biomass, no spring growth |
| Overwinter | More biomass, better N fixation | Must terminate before planting |
Plant fall cover crops 4-6 weeks before your first expected frost. Spring cover crops go in as soon as soil can be worked. Summer crops like buckwheat can fill gaps between harvests for a quick 35-day cover.
| Season | Best Crops | Days to Terminate |
|---|---|---|
| Fall | Winter rye, crimson clover | 150–180 |
| Spring | Oats, field peas | 60 |
| Summer | Buckwheat | 35 |
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Last Updated: Mar 9, 2026
This calculator is provided for informational and educational purposes only. Results are estimates and should not be considered professional financial, medical, legal, or other advice. Always consult a qualified professional before making important decisions. UseCalcPro is not responsible for any actions taken based on calculator results.