Organic Farm Advisory

The Plant & Pest Advisory serves NJ growers by reporting on important pests and recommending responses that are grounded in reproducible trials.

Articles in this section contain information helpful to the NJ commercial organic grower.

Sharing organic practice trial results between land-grant universities is a cost effective way to create a common knowledge base built on the strengths of individual programs. In the sidebar, find institutions with programs in organic agriculture which augment knowledge developed at the Rutgers New Jersey Ag Experiment Station.

Rutgers Cooperative Extension Field Guides: These concise guides help with decision making from pre-planting to harvest. For each crop listed, learn what pests to proactively look for as the season progresses, how to look for them, and when to take action.

Field Guide List

May 15, 2025 and

Vegetable IPM Update 5/15/25

Greetings from the Veg IPM team! No major changes have taken place between last week and this week, and with the rainy weather, scouting has been limited.

Sweet Corn

We’ve put out corn earworm pheromone traps throughout the state. While silking corn is the main target of CEW activity, we set the traps early to detect overwintering moths, which have become more common with warmer winters. As a reminder, we’re no longer using blacklight traps as of this year, and we’ll be reporting pheromone trap counts in the Plant Pest Advisory as the season progresses. So far, we haven’t spotted any corn pests through visual inspection.

Cole Crops 

A shiny black beetle with straight antennae stands on a leaf surrounded by circular feeding holes.

Flea beetle surrounded by feeding damage. Picture by Maria Cramer.

Flea beetle are active in various cole crops. This year, they have been especially prevalent in Napa cabbage and bok choy. Young plants are especially vulnerable to attack from flea beetles. The treatment threshold for flea beetles in heading cole crops is 50% infestation.

 

Two picture, the picture on the left shows a smooth caterpillar that tapers at both ends. The picture on the right shows a caterpillar that is fuzzy all over and does not taper at either end.

Left: Diamondback moth caterpillar, showing characteristic tapering at each end. Right: Imported cabbageworm caterpillar showing characteristic fuzziness. Pictures by Maria Cramer.

We’re seeing caterpillar activity (imported cabbageworm and diamondback moth) in cabbage and other cole crops. Treatment thresholds vary between crops and growth stage, but for heading cole crops between early vegetative and cupping, the treatment threshold is 30%. At this stage, sprayable Bt products (IRAC 11A) such as Dipel, Xentari, or Javelin can be effective on young caterpillars. Other materials approved for caterpillar control include Entrust/Radiant (IRAC 5), Proclaim (IRAC 6), Torac (IRAC 21A), and Exirel (IRAC 28). For Bt products and contact insecticides, coverage on the undersides the leaves is essential.

 

Tomatoes

In high tunnels and the first field plantings of tomatoes, we’re seeing limited aphid, thrips, and spider mite activity. If dealing with primarily aphids, products such as Beleaf (IRAC 29) are recommended, especially if plants have reached the flowering stage. For thrips, Entrust, Radiant (IRAC 5) and Torac (IRAC 21A) can be used. For spider mites, Nealta (IRAC 25) is an effective material that is more friendly to beneficial insects, but Portal (IRAC 21A) and other materials can be used to manage populations.

 

Please consult the Mid-Atlantic Commercial Vegetable Production Guide for a more comprehensive list of materials that are labeled for specific crops and pests. As always, be sure to follow label rates and application instructions.

Authors: Amanda Quadrel (Northern NJ Veg IPM coordinator) and Maria Cramer (Southern NJ Veg IPM coordinator)

 

Filed Under: Organic Production, vegetable, Vegetable Crops Tagged With: , , , ,
May 8, 2025 and

Vegetable IPM Update 5/08/25

Sweet Corn

We’ve put out corn earworm pheromone traps throughout the state. While silking corn is the main target of CEW activity, we set the traps early to detect overwintering moths, which have become more common with warmer winters. As a reminder, we’re no longer using blacklight traps as of this year, and we’ll be reporting pheromone trap counts in the Plant Pest Advisory as the season progresses.

Cole Crops 

A shiny black beetle with straight antennae stands on a leaf surrounded by circular feeding holes.

Flea beetle surrounded by feeding damage. Picture by Maria Cramer.

Flea beetle are active in various cole crops. This year, they have been especially prevalent in Napa cabbage and bok choy. Young plants are especially vulnerable to attack from flea beetles. The treatment threshold for flea beetles in heading cole crops is 50% infestation.

 

Two picture, the picture on the left shows a smooth caterpillar that tapers at both ends. The picture on the right shows a caterpillar that is fuzzy all over and does not taper at either end.

Left: Diamondback moth caterpillar, showing characteristic tapering at each end. Right: Imported cabbageworm caterpillar showing characteristic fuzziness. Pictures by Maria Cramer.

We’re seeing caterpillar activity (imported cabbageworm and diamondback moth) in cabbage and other cole crops. Treatment thresholds vary between crops and growth stage, but for heading cole crops between early vegetative and cupping, the treatment threshold is 30%. At this stage, sprayable Bt products (IRAC 11A) such as Dipel, Xentari, or Javelin can be effective on young caterpillars. Other materials approved for caterpillar control include Entrust/Radiant (IRAC 5), Proclaim (IRAC 6), Torac (IRAC 21A), and Exirel (IRAC 28). For Bt products and contact insecticides, coverage on the undersides the leaves is essential.

 

Tomatoes

In high tunnel tomatoes, we’re seeing limited aphid, thrips, and spider mite activity. If dealing with primarily aphids, products such as Beleaf (IRAC 29) are recommended, especially if plants have reached the flowering stage. For thrips, Entrust, Radiant (IRAC 5) and Torac (IRAC 21A) can be used. For spider mites, Nealta (IRAC 25) is an effective material that is more friendly to beneficial insects, but Portal (IRAC 21A) and other materials can be used to manage populations.

 

Please consult the Mid-Atlantic Commercial Vegetable Production Guide for a more comprehensive list of materials that are labeled for specific crops and pests. As always, be sure to follow label rates and application instructions.

Authors: Amanda Quadrel (Northern NJ Veg IPM coordinator) and Maria Cramer (Southern NJ Veg IPM coordinator)

 

Filed Under: Organic Production, vegetable, Vegetable Crops Tagged With: , , , ,
May 8, 2025

Registration Open for 2 Agricultural Supervisor Training Courses: In English and Spanish

Cornell Agricultural Workforce Development will be offering two Ag Supervisory Leadership courses for all agricultural operations starting in June for farms in the Northeastern Region including: Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont. Registration is currently open and closes on June 25. There are separate registration fees for New York residents and out of state residents. See below. 

The courses available are:
ASL101-SP: Transición a Supervisor (in Spanish)

Transition to Supervisor helps to develop leaders and focuses on skills to improve communication and manage conflict. Learn how to recognize our inherent biases and how to build better working relationships. Gain insight into your leadership style and learn how to effectively lead diverse and multicultural teams.

Course topics include:
How to make the mental transition to supervisor
How to develop effective working relationships
Essential communication skills
How to be the leader of a multicultural group
How to build better working relationships
Course begins: Friday, June 20, 2025
Live Zoom discussions: Thursdays, June 26 – July 31, 4:00–5:00 PM ET

Register for ASL101-SP Transición a Supervisor

ASL106: Ethics and Employment Regulations (in English)

In ASL106: Ethics and Employment Regulations, you’ll explore how to implement fair and ethical labor practices in agriculture and why they matter. You’ll learn to recognize and prevent sexual harassment, understand wage and hour laws, and apply Equal Employment Opportunity regulations to foster a respectful, inclusive workplace. The course also covers best practices for handling employee discipline and termination.

Course topics include:
Ethics and sustainability
Equal Employment Opportunity, laws and implications
Hiring regulations and practices
Safety issues in agriculture
Farm employee housing
Compensation regulations
Being an ethical supervisor
Course begins: Friday, June 20, 2025
Live Zoom discussions: Thursdays, June 26 – July 31, 3:00–4:00 PM ET

Register for ASL106: Ethics and Employment Regulations

Course costs:
$275 for NYS residents/$325 for out-of-state residents

Scholarship Opportunity for Dairy Producers:
Thanks to the Northeast Dairy Business Innovation Center (NEDBIC), eligible dairy producers can apply for a $100 scholarship to help cover registration fees. Scholarships are available to participants from qualifying states in the Northeast, including Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont.

Questions? Email cu-agworkforce@cornell.edu

Follow us on Facebook: www.facebook.com/cornellagworkforcedevelopment

Filed Under: Blueberry, Commercial Ag Updates, Cranberry, Field, Forage & Livestock, Food Safety, Fruit, Landscape, Nursery, & Turf, Nursery, Organic Production, Strawberry, training, Tree Fruit, Turf, vegetable, Vegetable Crops, Wine Grape Tagged With: , ,
April 24, 2025

Need a Manure Spreader? Nutrient Management Assistance Grants – Deadline 6/16/25

New Jersey Department of Agriculture (NJDA), Division of Agricultural and Natural Resources is offering the following grant opportunity:

Nutrient Management Assistance Grants
Available Funding: Up to $25,000
Application Deadline: June 16, 2025
Funding Period: Three Years

The New Jersey Department of Agriculture (NJDA), Division of Agricultural and Natural Resources is pleased to announce a funding opportunity to support manure spreader purchase and maintenance, and to establish a community use program for the manure spreader. This grant aims to advance nutrient management Best Management Practices (BMPs) across New Jersey farms by enabling the shared use of properly maintained equipment.

Eligible Applicants:
• New Jersey-based individuals
• Agricultural businesses
• Cooperatives
• Not-for-profit organizations (NFPs)
• Government agencies

Applicants should demonstrate a strong working relationship with local agricultural producers and must be committed to supporting nutrient management in their communities.

Program Highlights:
• Purchase and maintain a manure spreader
• Establish a community use program for the manure spreader with a minimum of five farms
• Support the implementation of Animal Waste Management Plans (AWMPs) with Nutrient Management Plans or nutrient budgets where the manure spreader will be used
• Implement all funded activities over a three-year period

For application materials and additional information, please visit: https://www.nj.gov/agriculture/grants/njdanutrientmanagementgrants.html

Filed Under: Christmas Trees, Commercial Ag Updates, Field, Forage & Livestock, Fruit, Landscape, Nursery, & Turf, Organic Production, vegetable, Vegetable Crops Tagged With: ,
March 24, 2025

Allium Leafminer Update 3/24/2025- First oviposition scars spotted

The first Allium leafminer (ALM) oviposition scars were reported in Cape May this past weekend (38.9588N, 74.9082W), suggesting that adults are active in the southern part of the state. ALM are active around 250 GDDs. If you want to know how many GDDs have accumulated in your area, the NEWA website https://newa.cornell.edu/ has a helpful GDD calculator. From the NEWA home screen, select the nearest weather station from the drop-down menu at the center of the page.  Next, scroll down to “Weather Tools” on the right side of the page and select “DD Calculator.”  Select your start date (1/01/25) and end date, as well as Degree Day Type (39 F) from the menu at the left of the page.  The site will automatically generate the accumulated GDD base 39 F to the last day of your requested sample, and then offer a forecast of accumulated GDD for the next week.

ALM can cause injury to chives, scallions, garlic, onions and leeks, but leeks and scallions seem to be the most effected. Look for neat rows of white spots descending from the upper tips of allium leaves (see photo below). Initial injury often occurs on the tallest leaves. Adults may be seen in warmer conditions at the tips of the leaves- look for small flies with grey-black bodies and yellow heads (see photo below).

If you are concerned about crop injury due to Allium leafminer, you may want to prepare for control efforts. Floating row covers, kept on until the first flight ends (around the end of May) can restrict ALM’s access to vulnerable plants. Adults can be targeted through insecticide sprays. Appropriate materials that are labeled for ALM control include spinosyns (Radiant, Entrust (OMRI approved)), pyrethroids (Mustang Maxx, Warrior), neonicotinoids (Scorpion, Venom), and the insect growth regulator Trigard. The first application should be applied 2- 3 weeks after initial detection of ALM flies (if you see oviposition scars or the fly itself) and subsequent sprays should be completed in 1–2-week intervals. Two or three sprays should provide adequate control.

Field Scouting Guide: Allium Leafminer - Growing Produce

Notice the white oviposition scars and an adult female ALM. Photo: Brian A. Nault, Cornell AgriTech. 

If you have any questions/concerns, feel free to reach out to me at amanda.quadrel@rutgers.edu or 732-742-8441.

Filed Under: Organic Production, vegetable, Vegetable Crops
March 20, 2025

Allium Leafminer Update 3/20/2025

Happy first day of Spring! Many parts of New Jersey are close to accumulating 250 growing degree days (GDDs) base 39˚F, which is when the first emergence of Allium leafminer (ALM) adults is predicted to occur. In some areas of New Jersey, 250 GDDs are forecasted to be surpassed as early as this weekend. In Cape May, oviposition scars have already been spotted. If you would like to know how many GDDs have accumulated in your area, the NEWA website https://newa.cornell.edu/ has a helpful GDD calculator. From the NEWA home screen, select the nearest weather station from drop down menu at the center of the page.  Next, scroll down to “Weather Tools” on the right side of the page, and select “DD Calculator”.  Select your start date (1/01/25) and end date, as well as Degree Day Type (39 F) from the menu at the left of the page.  The site will automatically generate the accumulated GDD base 39F to the last day of your requested sample, and then offer a forecast of accumulated GDD for the next week.

ALM can cause injury to chives, scallions, garlic, onions and leeks, but leeks and scallions seem to be the most effected. Look for neat rows of white spots descending from the upper tips of allium leaves (see photo below). Initial injury often occurs on the tallest leaves. Adults may be seen in warmer conditions at the tips of the leaves- look for small flies with grey-black bodies and yellow heads (see photo below).

If you are concerned about crop injury due to Allium leafminer, you may want to prepare for control efforts. Floating row covers, kept on until the first flight ends (around the end of May) can restrict ALM’s access to vulnerable plants. Adults can be targeted through insecticide sprays. Appropriate materials that are labeled for ALM control include spinosyns (Radiant, Entrust (OMRI approved)), pyrethroids (Mustang Maxx, Warrior), neonicotinoids (Scorpion, Venom), and the insect growth regulator Trigard. The first application should be applied 2- 3 weeks after initial detection of ALM flies (if you see oviposition scars or the fly itself) and subsequent sprays should be completed in 1–2-week intervals. Two or three sprays should provide adequate control.

Field Scouting Guide: Allium Leafminer - Growing Produce

Notice the white oviposition scars and an adult female ALM. Photo: Brian A. Nault, Cornell AgriTech. 

If you have any questions/concerns, feel free to reach out to me at amanda.quadrel@rutgers.edu or 732-742-8441.

Filed Under: Organic Production, vegetable, Vegetable Crops