Prior to field preparation, have soil tested to establish baseline pH and nutrient levels. Manage nutrients according to soil test results, soil types, and region-specific guidelines presented in Table 1, below. Note the following general considerations:
Maintain a pH of 6.5. In regions where clubroot is a concern, apply lime to raise pH into the range of 6.8 – 7.2.
Boron can be applied as an additive to fertilizer. See table for the recommended amount for your area.
Fertilizer inputs are generally split into multiple applications timed to critical stages in plant growth. Base inputs on soil test results, and do not exceed total recommended amounts for your region. Include nitrogen credits in total inputs.
Abnormalities can result from overfertilizing as well as from nutrient deficiencies. For example, hollow stem can result from too little boron or too much nitrogen.
A separate article describes how to time nitrogen application to avoid loose heads.
New England
Recommended Nutrients Based on Soil Tests |
|||||||||
If soil levels of boron are low, apply 3 lbs. boron per acre as an additive to fertilizer before planting | Nitrogen lbs/acre | P2O5 lbs/acre | K2O lbs/acre | ||||||
Soil Phosphorus Level | Soil Potassium Level | ||||||||
very low | low | opti-mum | above opti-mum | very low | low | opti-mum | above opti-mum | ||
Total Recommended | 160 | 150 | 100 | 50 | 0 | 175 | 120 | 50 | 0 |
Broadcast & incorporate | 100 | 150 | 100 | 50 | 0 | 175 | 125 | 50 | 0 |
Sidedness 4 weeks after transplant | 60 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Source: University of Massachusetts Amherst. 2016-2017 New England Vegetable Management Guide: Cabbage, Broccoli, Cauliflower, and Other Brassica Crops.
New York
Recommended Nutrients Based on Soil Tests |
|||||||
Add 1 to 2 lbs boron/acre to fertilizer | Nitrogen lbs/acre | P2O5 lbs/acre | K2O lbs/acre | ||||
Soil Phosphorus Level | Soil Potassium Level | ||||||
low | med | optimal | low | med | optimal | ||
Total Recommended | 100-120 | 120 | 80 | 40 | 160 | 120 | 60 |
Broadcast & disk-in | 40 | 80 | 40 | 40 | 120 | 80 | 40 |
Band place with planter | 40 | 40 | 40 | 0 | 40 | 40 | 20 |
Sidedress 4 weeks after seeding or transplanting | 20-40 | 0 | 0 | 0 | 0 | 0 | 0 |
Source: Cornell Cooperative Extension. 2013. Integrated Crop & Pest Management Guidelines for Commercial Vegetable Production. Chapter 15: Cabbage, Broccoli, Cauliflower, and Brussels Sprouts.
Mid-Atlantic
Recommended Nutrients Based on Soil Tests |
|||||||||
Apply 1.5 to 3 lbs. boron per acre in mixed fertilizer | Nitrogen lbs/acre | P2O5 lbs/acre | K2O lbs/acre | ||||||
Soil Phosphorus Level | Soil Potassium Level | ||||||||
low | med | high (opt.) | very high | low | med | high (opt.) | very high | ||
Total Recommended | 150-200 | 200 | 100 | 50 | 01 | 200 | 100 | 50 | 01 |
Broadcast & disk-in | 50-100 | 200 | 100 | 50 | 01 | 200 | 100 | 50 | 01 |
Sidedress 2 to 3 weeks after planting | 50 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Sidedress 4 to 6 weeks after planting | 50 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
1 Recommendation for Virginia is 25 lbs/acre
Source: Rutgers NJAES Cooperative Extension Publication E001. 2016 – 2017 Mid-Atlantic Commercial Vegetable Production Recommendations.
Southeast
Recommended Nutrients Based on Soil Tests |
|||||||||
Apply 1.5 to 3 lbs. boron per acre in mixed fertilizer | Nitrogen lbs/acre | P2O5 lbs/acre | K2O lbs/acre | ||||||
Soil Phosphorus Level | Soil Potassium Level | ||||||||
low | med | opti-mal | very high | low | med | opti-mal | very high | ||
Total Recommended | 125-170 | 200 | 100 | 50 | 0 | 200 | 100 | 50 | 0 |
Broadcast & disk-in | 50-100 | 150 | 100 | 50 | 0 | 150 | 100 | 50 | 0 |
Sidedress 2 to 3 weeks after planting | 50 | 50 | 0 | 0 | 0 | 50 | 0 | 0 | 0 |
Sidedress every 2 to 3 weeks after initial sidedressing | 25 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Source: Southeastern Vegetable Extension Workers. 2017 Southeastern U.S. Vegetable Crop Handbook.