Edible bean production contributes substantially to farming enterprises in Minnesota. Edible beans are beans grown for human consumption. At this time, there is no data suggesting that one type of edible bean should be fertilized differently than another.
Nitrogen guidelines
Nitrogen (N) fertilizer guidelines can be based either on the results of the soil nitrate test or the consideration of yield goal, previous crop, and soil organic matter content.
The soil nitrate test is appropriate for the fine-textured soils of western and northwestern Minnesota. It should not be used for soils that have a sand, loamy sand, or sandy loam texture.
Nitrogen management practices should be adjusted according to soil texture. Split applications are suggested for sandy soils (sands, loamy sands, sandy loams).
- Apply approximately one-half of the suggested nitrogen about two weeks after planting.
- Apply the remainder two weeks later.
Nitrogen fertilizer formula for dry edible bean plantings
- Suggested N in lb/acre = [(.05) x YG] - STN(0-24 in.) - NPC
Nitrogen formula variables
- YG = yield goal, bushels per acre
- STN(0-24 in.) = nitrate-nitrogen (NO3--N) measured to a depth of 2 feet, in pounds per acre
- NPC = amount of N supplied by the previous crop, in pounds per acre
Split applications are not needed if soils are not sandy. The nitrogen needed for these fields can be applied in the fall for western Minnesota, before planting, or as a side-dress treatment. Considering the late date of planting common with edible bean production, a spring pre-plant application followed by incorporation would be preferred.
Do not apply any N in contact with the seed at planting.
There is no evidence to suggest that there is a superior source of nitrogen for edible bean production. If applied so as to prevent loss, all nitrogen fertilizers should have an equal effect on yield.
Suggested nitrogen credits for various crops that might precede dry edible beans in a crop rotation. Use these credits when the soil nitrate test is used.
| Previous Crop | First year N credit (lb N/acre) |
|---|---|
| Soybean | 20 |
| Edible beans, field peas | 10 |
| Harvested sweet clover | 10 |
| Harvested red clover | 35 |
| Harvested alfalfa* or non-harvested sweet clover | |
| 4-5 plants/ft2 | 75 |
| 2-3 plants/ft2 | 50 |
| 1-2 plants/ft2 | 25 |
| 1 or fewer plants/ft2 | 0 |
| Sugar beet | |
| Yellow leaves at harvest | 0 |
| Light-green leaves at harvest | 15-30 |
| Dark-green leaves at harvest | 60-80 |
*If 3rd or 4th cutting was not harvested, add 20 lb. N/acre to the N credits listed.
Nitrogen guidelines for dry edible beans when the soil nitrate test is not used*
| Crop grown last year | Organic matter level** | Below 1450 lb/acre | 1451-1900 lb/acre | 1901-2400 lb/acre | 2400-2900 lb/acre | 2900+ lb/acre |
|---|---|---|---|---|---|---|
| Alfalfa (4+ plants/ft2) | Low | 0 lb N/acre | 0 lb N/acre | 0 lb N/acre | 0 lb N/acre | 0 lb N/acre |
| Alfalfa (4+ plants/ft2) | Medium/High | 0 | 0 | 0 | 0 | 0 |
| Alfalfa {2-3 plants/ft2) | Low | 0 | 0 | 20 | 40 | 60 |
| Alfalfa (2-3 plants/ft2) | Medium/High | 0 | 0 | 0 | 10 | 30 |
| Soybeans or alfalfa (1 or less plants/ft2) | Low | 0 | 20 | 40 | 60 | 80 |
| Soybeans or alfalfa (1 or less plants/ft2) | Medium/High | 0 | 0 | 0 | 30 | 50 |
| Edible beans, field peas, harvested sweet clover | Low | 20 | 40 | 60 | 80 | 100 |
| Edible beans, field peas, harvested sweet clover | Medium/High | 0 | 0 | 30 | 50 | 70 |
| Group 1 Crops (see below) | Low | 0 | 0 | 0 | 25 | 45 |
| Group 1 Crops | Medium/High | 0 | 0 | 0 | 0 | 25 |
| Group 2 Crops | Low | 40 | 60 | 80 | 100 | 120 |
| Group 2 Crops | Medium/High | 10 | 30 | 50 | 70 | 90 |
*Based on expected yield of the crop in pounds per acre. **Low = less than 3.0%; Medium/High = 3.0% or more
Crops in Group 1: Alsike clover, birdsfoot trefoil, grass/legume hay, grass legume pasture, fallow, red clover.
Crops in Group 2: Alfalfa (0-1 plants/ft.2), barley, buckwheat, canola, corn, flax, grass hay, grass pasture, oat, potato, rye, sorghum-sudan, sugarbeet, sunflower, sweet corn, triticale, vegetables, wheat.
Phosphate and potash guidelines
Soil tests are intended to be an index of crop response and not a direct measure of the amount of nutrient in the soil. The phosphorus (P) status of Minnesota soils is determined by using either the Bray or the Olsen analytical procedure.
- The Bray soil test uses a strong acid to extract P from the soil. In situations where carbonates are present in the soil, the acid in the Bray solution can be neutralized reducing the amount of P extracted and the effectiveness of the test.
- The Olsen test provides more accurate results if the soil pH is 7.4 or higher as it is not affected by carbonates in the soil.
- Both tests can be accurately used in situations where high soil pH is not an issue but values obtained from the Olsen tests will be lower for the same soil test classification range since the Bray and Olsen test extract P out of different pools of available P in the soil.
The guidelines listed in these tables are suggested for either banded or broadcast applications.
Do not apply any fertilizer in contact with the seed.
Phosphate fertilizer guidelines*
| Expected Yield Bray-P1 Expected Yield Olsen |
0-5 ppm 0-3 ppm |
6-10 ppm 4-7 ppm |
11-15 ppm 8-11 ppm |
16-20 ppm 12-15 ppm |
21+ ppm 16+ ppm |
|---|---|---|---|---|---|
| Below 1401 lb/acre | 30 lb/acre | 20 lb/acre | 15 lb/acre | 0 lb/acre | 0 lb/acre |
| 1401-1900 | 35 | 25 | 15 | 0 | 0 |
| 1901-2400 | 45 | 30 | 20 | 10 | 0 |
| 2401-2900 | 55 | 40 | 25 | 10 | 0 |
| 2900+ | 60 | 45 | 25 | 10 | 0 |
*Pounds of P2O5 suggested to apply per acre for dry edible bean production based on either the Bray-P1 or Olsen soil methods test reported in parts per million (ppm). Use one of the following equations if a P205 recommendation for a specific yield goal is desired.
- P205 Rec = [.0231-.0011 (Bray P, ppm)] (Yield Goal)
- P205 Rec = [.0231-.0014 (Olsen P, ppm)] (Yield Goal)
Potash fertilizer guidelines*
| Expected Yield | K: 0-40 ppm | K: 40-80 ppm | K: 80-120 ppm | K:120-160 ppm | K: 160+ ppm |
|---|---|---|---|---|---|
| Below 1401 lb/acre | 35 lb/acre | 15 lb/acre | 0 lb/acre | 0 lb/acre | 0 lb/acre |
| 1401-1900 | 45 | 15 | 0 | 0 | 0 |
| 1901-2400 | 55 | 20 | 0 | 0 | 0 |
| 2401-2900 | 65 | 25 | 0 | 0 | 0 |
| 2900+ | 75 | 30 | 0 | 0 | 0 |
*Pounds of K2O suggested to apply per acre for dry edible bean production based on the ammonium acetate potassium (K) test reported in parts per million (ppm). Use the following equation if a K2O recommendation for a specific soil test value and a specific yield goal is desired.
- K2ORec = [.0346-.00042 (K Soil Test, ppm)] (Yield Goal)
Other nutrient needs
Past research with edible beans has indicated that zinc is the only micronutrient that may be needed in a fertilizer program.
Zinc application guidelines (lb/acre) for edible bean production
| Zinc soil test* | Starter lb/acre | Broadcast lb/acre |
|---|---|---|
| 0.00-0.25 ppm | 2 | 10 |
| 0.26-0.50 | 2 | 10 |
| 0.51-0.75 | 1 | 5 |
| 0.76-1.00 | 0 | 0 |
*Zinc extracted by the DTPA procedure.
There is no research suggesting that other nutrients are needed in a fertilizer program for edible bean production.
Caution:
Do not apply any fertilizer in contact with the seed at planting.
Reviewed in 2023