Cover Crop Selector

About the Cover Crop Selector

Cover crops protect and improve soil between cash crop seasons. Different species excel at different goals: legumes fix nitrogen, grasses produce biomass for erosion control, brassicas break compaction with deep taproots, and vigorous species suppress weeds through fast canopy closure.

This selector page ranks cover crop species based on your main management objective. Enter the goal, and it recommends species suited to that purpose, along with approximate seeding rates and expected benefits. Many farms plant multi-species mixes to address multiple goals simultaneously.

Use it with frost dates and crop rotation planning so the recommended species also fit the open window between cash crops.

When This Page Helps

The hard part is not finding a cover crop list; it is matching species to the field objective and the time window available. This page narrows that choice.

How to Use the Inputs

1. Select your primary management goal from the dropdown.
2. Review the ranked list of recommended cover crop species.
3. Note the approximate seeding rate for each species.
4. Consider a multi-species mix for multiple benefits.
5. Check species winterhardiness for your zone before planting.
6. Plan termination timing to avoid interference with the following cash crop.

Example Calculation

Tips & Best Practices

• Plant cover crops as early as possible after cash crop harvest for maximum growth.
• Mixes of 3-5 species outperform single species for overall soil health improvement.
• Terminate cover crops 10-14 days before planting the cash crop to avoid moisture and nutrient competition.
• Consider aerial seeding into standing cash crops if harvest timing is late.
• Budget $15-$40/ac for cover crop seed depending on species and seeding rate.
• Many NRCS programs offer cost-share payments for cover crop adoption.

Cover Crop Species Categories

Grasses (cereal rye, oats, triticale) produce high biomass, scavenge excess nitrogen, and suppress weeds. Legumes (crimson clover, hairy vetch, peas) fix nitrogen and provide N credit to the following crop. Brassicas (radishes, turnips, rapeseed) break compaction with deep taproots and cycle nutrients from depth.

Multi-Species Mixes

Mixes capture synergies between species. A common three-way mix is cereal rye + crimson clover + radish, which combines weed suppression, nitrogen fixation, and compaction relief. Mixes also improve biodiversity, support pollinators, and provide more consistent performance across variable field conditions.

Economics of Cover Crops

Seed cost ranges from $10-$40/ac. Establishment cost adds $5-$15/ac for drilling or aerial application. Benefits include reduced fertilizer cost (N credits), improved yields, reduced erosion, and potential NRCS cost-share payments. The net economic impact is typically positive within 2-3 years of adoption.

Frequently Asked Questions

• What is the best general-purpose cover crop?

  Cereal rye is the most versatile and widely adapted cover crop. It establishes quickly in fall, survives winter in most zones, produces excellent biomass for weed suppression, and is easy to terminate in spring.

• How much nitrogen do cover crops fix?

  Legume cover crops can fix 40-200 lbs N/ac depending on species, growth duration, and termination timing. Crimson clover and hairy vetch are among the highest N producers when allowed to reach flowering before termination.

• When should I terminate cover crops?

  Terminate at least 10-14 days before planting the cash crop. Use herbicide burndown, roller crimping, or tillage depending on your system. Later termination produces more biomass but increases the risk of cash crop interference.

• Do cover crops reduce yields of the following crop?

  When managed properly (timely termination, adequate planting window), cover crops typically maintain or increase yields through improved soil health, moisture retention, and nitrogen credits. Poorly managed cover crops can tie up moisture or N.

• Can I graze cover crops?

  Yes. Many farms graze cover crops, especially multi-species mixes with brassicas and legumes. Managed grazing provides additional revenue while still delivering soil health benefits from the root growth and residual biomass.

• What if I have a short window between harvest and freeze?

  Choose fast-establishing species like cereal rye, oats, or radishes that can germinate and grow quickly in cool temperatures. Radishes winterkill and decompose, reducing spring management needs.