Cornell Vegetable Program Enrollment

Program Areas

  • Food Safety
  • Variety Evaluation
  • Market Development
  • Pest Management
  • Cultural Practices

Enrollment Benefits

  • Telephone / Email Consultations
  • VegEdge Newsletter
  • Direct Mailings
  • Educational Meetings & Conferences
  • In-Field Educational Opportunities
  • On-Farm Research Trials

CVP Enrollment Form (PDF; 261KB)

Enrollee Login

Password:

Log In To Access:

  • Issues of VegEdge Newsletters

Not an Enrollee? Enroll Now!

Online Enrollment Form

Adding Cover Crops to Your Farm? Consider the Herbicide Rotation Restrictions

Darcy Telenko, Extension Vegetable Specialist
Cornell Vegetable Program

December 19, 2016

Adding Cover Crops to Your Farm? Consider the Herbicide Rotation Restrictions
Many of our vegetable farms have begun utilizing cover crops on their farm to improve soil health (organic matter and soil structure); nitrogen production; soil microbial activity; weed, disease and pest suppression; and soil and water conservation. When identifying the best cover crop to plant on your farm there are a number of considerations such as the main goal for utilizing the cover crop, when and where they will be used in the rotation, and management practices for the cover crop that need to be implemented to achieve the best results.

One challenge to adding cover crops to your vegetable production system is that herbicides with residual activity may interfere with cover crop establishment and growth. Residual herbicides are a key management tool in vegetable production, especially for management of difficult weeds and their potential to help control herbicide-resistant weeds. Some questions to consider when utilizing a cover crop and how well it will work with an herbicide program include:
  • Will the cover crop be grazed or harvest for feed or forage? If yes, then the rotation restriction on the label must be followed to protect the food chain from pesticide residues and/or crop from injury. If a crop is not on the label, then the rotation restriction for "other crops" must be followed.
  • How sensitive is the cover crop to herbicide carryover? Research has found that radish seems to be one of the most sensitive crops, while cereal rye and hairy vetch were the least. Residual herbicides with grass activity can interfere with establishment of some grass cover crops, while others can interfere with some broadleaf cover crops species. So it will all depend on the herbicide used and cover crop species being planted. 
  • How long can I expect the herbicide to remain active in the soil? There is great variability on persistence of herbicides in the soil, many labels will contain specific rotation restrictions. Herbicides with soil activity and a relatively long half-life include: Atrazine (60 days), Stinger (40 days), Pursuit (60-90 days) are a few examples.
  • When was the herbicide applied and when do I plan to seed the cover crop? Much research has been conducted on residual herbicides and fall-seeded cover crop. It is expected that the longer the time period between herbicide application and cover crop seeding the lower the risk to injury, but we may see a greater need of understanding our herbicide programs a may play an important role as we see changes in when cover crops are being seeded.
  • Should I increase my cover crop seeding rate? Higher seeding rates may be an option if there is marginal sensitivity to the herbicide - but there's not guarantee it will result in a higher stand of the cover crop and can lead to higher cover crops costs. 
  • Can I use a postemergence herbicide after interseeding my cover crop? To minimize risk, only select herbicides that have crop and cover crop on herbicide label and follow application restrictions listed on label such as crop and weed sizes. 
To help answer some of these we have created a table for guidance on the "Commonly used herbicides on vegetables in New York and rotation considerations for cover crops." 

Sources: "Common Corn and Soybean Herbicides, Estimated Half-Lives, Cash Crop Restrictions and Their Potential to Injure Fall Cover Crops", Penn State Extension, Curran and Lingenfelter, 2012, available at: http://extension.psu.edu/plants/crops/soilmanagement/cover-crops/herbicidepersistence/herbicide-carryover-table

"Managing risk when using herbicides and cover crops in corn and soybean" Lizabeth Stahl, Extension Educator - Crops https://www.extension.umn.edu/agriculture/weeds/herbicides/docs/cover-crops-and-herbicides.pdf


Common Herbicides on Vegetables in NY and Considerations for Cover Crops, 8.5x11 (pdf; 436KB)

Common Herbicides on NY Vegetables and Considerations for Cover Crops, 11x17 (pdf; 385KB)

more crops
Asparagus

Asparagus

Beets

Beets

Broccoli

Broccoli

Brussels Sprouts

Brussels Sprouts

Cabbage

Cabbage

Carrots

Carrots

Cauliflower

Cauliflower

Cucumbers

Cucumbers

Dry Beans

Dry Beans

Eggplant

Eggplant

Ethnic Vegetables

Ethnic Vegetables

Garlic

Garlic

Horseradish

Horseradish

Kohlrabi

Kohlrabi

Leeks

Leeks

Lettuce / Leafy Greens

Lettuce / Leafy Greens

Melons

Melons

Mushrooms

Mushrooms

Onions

Onions

Parsnips

Parsnips

Peas

Peas

Peppers

Peppers

Potatoes

Potatoes

Pumpkins / Gourds

Pumpkins / Gourds

Radishes

Radishes

Rhubarb

Rhubarb

Rutabaga

Rutabaga

Snap Beans

Snap Beans

Squash - Summer

Squash - Summer

Squash- Winter

Squash- Winter

Sweet Corn

Sweet Corn

Sweet Potatoes

Sweet Potatoes

Tomatoes

Tomatoes

Turnips

Turnips

more crops
view calendar of events

Upcoming Events

2025 Potato Advisory Meeting

Event Offers DEC Credits

December 16, 2025
Canandaigua, NY

Come hear the latest on insect pest control and fertility management in potatoes from Cornell University experts. Potato variety trial updates will be shared too. After lunch will be the Empire State Potato Grower's Meeting. 1.5 DEC credits in 10, 1a, and 23.

View 2025 Potato Advisory Meeting Details

2026 Finger Lakes Produce Auction Winter Growers Meeting

Event Offers DEC Credits

January 8, 2026
Penn Yan, NY

At this vegetable grower-focused meeting, ag industry experts will discuss food safety, disease management in strawberries, the benefits of using cover crops, plus more. Two grower panel discussions will focus on pest management techniques and irrigation. DEC recertification credits offered in categories 10, 1a, 21, 22, 23, and 24.

View 2026 Finger Lakes Produce Auction Winter Growers Meeting Details

Announcements

Cornell Crop and Pest Management Guidelines Paused

From Cornell IPM:

Highlighting its commitment to quality and long-term sustainability, Cornell Integrated Pest Management's Pesticide Safety Education Program has announced a pause in production of the 2026 Cornell Crop and Pest Management Guidelines.

Cornell IPM Director Alejandro Calixto said this temporary measure is the result of a comprehensive reimagining process facilitated by Illume Projects of Ithaca, which included end-user interviews, internal surveys and sales data analytics.

"It became clear to us that we cannot continue producing the guidelines and fully restructure them at the same time," Calixto said. "By pausing production, we can dedicate all available resources and time to rebuilding the production process, ensuring that when we re-launch in 2027, the guidelines will reflect a modernized approach built around the grower and other user experience."

A series of annually updated reference manuals produced by Cornell IPM and the College of Agriculture and Life Sciences (CALS), the Cornell Crop and Pest Management Guidelines are widely used by farmers, agronomists, crop consultants and extension educators in New York and throughout the Northeast. They include information about current IPM recommendations, pesticide options, cultural practices, nutrient management, disease, insect and weed identification and resistance-management strategies.

Calixto and Pesticide Safety Education Program Lead Mike Helms will spearhead efforts to restructure the guideline process over the next 12 months, with a goal of launching a more streamlined, user-friendly version in 2027.

Limited copies of the 2025 guidelines remain available for purchase while supplies last through The Cornell Store. The 2026-2027 Greenhouse Guidelines will be available.

For more information contact Helms at mjh14@cornell.edu.


NEWSLETTER  |   CURRENT PROJECTS  |   IMPACT IN NY  |   SPONSORSHIP  |   RESOURCES  |   SITE MAP