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Dried edible bean fertilizer recommendations
Dried edible bean is an important part of the rotations for central, westcentral and northwestern Minnesota farm enterprises.
Here, you’ll find fertilizer guidelines for edible bean in Minnesota.
Suggestions are adjusted for growing situations. Guidelines appropriate for nonirrigated finetextured soils may not be appropriate for irrigated sandy soils, and vice versa.
Nitrogen
Optimum yields of this crop depend on efficiently using nitrogen (N) fertilizers.
You can base N use guidelines on the results of a soil NO_{3}^{}N test or considering the combination of expected yield, previous crop and soil organic matter content.
The soil NO_{3}^{}N test is appropriate for western Minnesota (Figure 1), but isn’t recommended for sandy soils, even in western Minnesota.
Recommended N = (0.05) (EY)  STN_{(024 in.)}  N_{Pc}
Where:

EY = Expected yield, in pounds per acre.

STN = Nitratenitrogen (NO_{3}^{}N) measured to a depth of 24 inches, in pounds per acre.

N_{pc} = amount of N supplied by the previous legume crop, in pounds per acre.
Table 1 summarizes these N credits.
Table 1 shows credits for various legume crops that might precede the edible bean crop in the rotation. Use these credits when using the soil nitrate test.
Table 1: Nitrogen credits
Legume crop  Firstyear nitrogen credit 

Harvested alfalfa: 4 or more plants per square foot  70 lbs. of N per acre 
Harvested alfalfa: 2 to 3 plants per square foot  50 lbs. of N per acre 
Harvested alfalfa: 1 or fewer plants per square foot  20 lbs. of N per acre 
Red clover  35 lbs. of N per acre 
Table 2 summarizes N fertilizer guidelines for situations where the soil NO_{3}^{}N test isn’t used. These suggestions are appropriate for edible bean production on finetextured soils.
When grown on sandy soils under irrigation, use the standard guideline of 120 pounds of N per acre. If edible beans follow alfalfa on sandy soils, an N credit of 70 pounds of N per acre for the alfalfa crop is suggested.
Table 2 shows recommendations for edible bean grown on nonirrigated finetextured soil and when a soil NO_{3}^{}N test isn’t used.
Table 2: Nitrogen guidelines for edible bean
Crop grown last year  Organic matter level  Expected yield: 1,4001,900 lbs. per acre  Expected yield: 1,9012,400 lbs. per acre  Expected yield: 2,4012,900 lbs. per acre  Expected yield: 2,901+ lbs. per acre 

Alfalfa (4+ plants per square foot)  Low  0 lbs. of N per acre  0 lbs. of N per acre  0 lbs. of N per acre  0 lbs. of N per acre 
Alfalfa (4+ plants per square foot)  Medium and high  0 lbs. of N per acre  0 lbs. of N per acre  0 lbs. of N per acre  0 lbs. of N per acre 
Alfalfa (2 to 3 plants per square foot)  Low  0 lbs. of N per acre  20 lbs. of N per acre  40 lbs. of N per acre  60 lbs. of N per acre 
Alfalfa (2 to 3 plants per square foot)  Medium and high  0 lbs. of N per acre  0 lbs. of N per acre  10 lbs. of N per acre  30 lbs. of N per acre 
Group 1 crops (see below)  Low  0 lbs. of N per acre  0 lbs. of N per acre  25 lbs. of N per acre  45 lbs. of N per acre 
Group 1 crops (see below)  Medium and high  0 lbs. of N per acre  0 lbs. of N per acre  0 lbs. of N per acre  25 lbs. of N per acre 
Group 2 crops (see below)  Low  60 lbs. of N per acre  80 lbs. of N per acre  100 lbs. of N per acre  120 lbs. of N per acre 
Group 2 crops (see below)  Medium and high  30 lbs. of N per acre  50 lbs. of N per acre  70 lbs. of N per acre  90 lbs. of N per acre 
*Low = Less than 3.0%; Medium and high = 3.0% or more
Crops in Group 1:
Alsike clover, birdsfoot trefoil, grass/legume hay, grass legume pasture, fallow and red clover.
Crops in Group 2:
Barley, buckwheat, canola, corn, grass hay, grass pasture, oat, potato, rye, sorghumsudan, sugarbeet, sunflower, sweet corn, triticale and wheat.
Crops not considered previous crops
Because of the high potential for diseases, if edible bean should follow soybeans, edible bean, peas and other crops of edible bean, these crops aren’t considered previous crops in the rotation.
Nitrogen application timing
Timing the nitrogen application is an important consideration for edible bean production.
To minimize damage from white mold, it’s important to keep the canopy open as much as possible. The canopy may be closed at flowering if all the N fertilizer is applied before planting.
This is why split applications of fertilizer N are suggested, especially for sandy soils. Research shows delayed applications of fertilizer N don’t reduce yields.
You can make the first application approximately two weeks after planting, and the second application as late as it’s practical for field equipment. Time the second application so the equipment doesn’t damage the crop.
Table 3 summarizes current phosphate guidelines. Guidelines for potash use are in Table 4. The guidelines in these tables are for both broadcast and banded applications.
There’s no research suggesting one placement is more efficient than the other. Recent research suggests these immobile nutrients, when applied in a band near the seed at planting, produce substantial yield increases.
Banded applications are an excellent option when suggested rates are low.
Use one of the following equations if you want a phosphate guideline for a specific soil test and a specific expected yield.
 Recommended P_{2}O_{5} = [0.0231  (0.0011) (Bray P in ppm)] (Expected yield)
 Recommended P_{2}O_{5} = [0.0231  (0.0014) (Olsen P in ppm)] (Expected yield)
Table 3: Phosphate fertilizer guidelines for edible bean production
Expected yield  P soil test: 05 parts per million (ppm) Bray and 03 ppm Olsen  P soil test: 610 ppm Bray and 47 ppm Olsen  P soil test: 1115 ppm Bray and 811 ppm Olsen  P soil test: 1620 ppm Bray and 1215 ppm Olsen  P soil test: 21+ ppm Bray and 16+ ppm Olsen 

1,4001,900 lbs. per acre  35 lbs. of P2O5 per acre  25 lbs. of P2O5 per acre  15 lbs. of P2O5 per acre  0 lbs. of P2O5 per acre  0 lbs. of P2O5 per acre 
1,9012,400 lbs. per acre  45 lbs. of P2O5 per acre  30 lbs. of P2O5 per acre  20 lbs. of P2O5 per acre  10 lbs. of P2O5 per acre  0 lbs. of P2O5 per acre 
2,4012,900 lbs. per acre  55 lbs. of P2O5 per acre  40 lbs. of P2O5 per acre  25 lbs. of P2O5 per acre  10 lbs. of P2O5 per acre  0 lbs. of P2O5 per acre 
2,901+ lbs. per acre  60 lbs. of P2O5 per acre  45 lbs. of P2O5 per acre  25 lbs. of P2O5 per acre  10 lbs. of P2O5 per acre  0 lbs. of P2O5 per acre 
In table 4 use the following equation if you want a potash guideline for a specific soil test and a specific expected yield:
Recommended K_{2}O = [0.0346  (0.00042) (Soil test K in ppm)] (Expected yield)
Table 4: Potash fertilizer guidelines for edible bean production
Expected yield  K soil test: 040 ppm  K soil test: 4080 ppm  K soil test: 80120 ppm  K soil test: 120160 ppm  K soil test: 160+ ppm 

1,4001,900 lbs. per acre  45 lbs. of K2O per acre  15 lbs. of K2O per acre  0 lbs. of K2O per acre  0 lbs. of K2O per acre  0 lbs. of K2O per acre 
1,9012,400 lbs. per acre  55 lbs. of K2O per acre  20 lbs. of K2O per acre  0 lbs. of K2O per acre  0 lbs. of K2O per acre  0 lbs. of K2O per acre 
2,4012,900 lbs. per acre  65 lbs. of K2O per acre  25 lbs. of K2O per acre  0 lbs. of K2O per acre  0 lbs. of K2O per acre  0 lbs. of K2O per acre 
2,901+ lbs. per acre  75 lbs. of K2O per acre  30 lbs. of K2O per acre  0 lbs. of K2O per acre  0 lbs. of K2O per acre  0 lbs. of K2O per acre 
Past research with the edible bean crop has indicated that zinc (Zn) is the only micronutrient that may be needed in a fertilizer program. Table 5 lists Zinc suggestions for both starter and broadcast application.
Research has shown no other nutrients are needed in a fertilizer program.
For the Zinc soil test, zinc was extracted by the diethylentriamene pentaacetate (DTPA) procedure.
Table 5: Zinc suggestions for edible bean production in Minnesota
Zinc soil test  Zinc to apply: Broadcast  Zinc to apply: Starter 

0.00.25 parts per million (ppm)  10 lbs. per acre  2 lbs. per acre 
0.260.50 ppm  10 lbs. per acre  2 lbs. per acre 
0.500.75 ppm  5 lbs. per acre  1 lbs. per acre 
0.761.00 ppm  0 lbs. per acre  0 lbs. per acre 
1.01+ ppm  0 lbs. per acre  0 lbs. per acre 
Caution: Don’t apply any fertilizer in contact with the seed at planting.
Reviewed in 2018