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Plant Diseases:

Diagnosis and Prevention

Common plant diseases can seriously impact your plants and crop yield. Taking preventative measures is the best way to ensure your plants stay disease-fee all season long. Learn about how to practice prevention, diagnose and treat common garden diseases with this collection of resources!

Tomato Diseases and Problems - Part 1 

Author: Burpee Gardening

The video presents the most common tomato diseases and problems specifically: septoria, blossom end rot, and early blight.

Tomato Diseases and Problems - Part 2 

Author: Burpee Gardening

The video presents the most common tomato diseases and problems specifically: bacterial speck and spot, fruit cracking, and stink bug damage.

How to Prune Tomatoes to Increase Yields, Prevent Disease, and Ripen Fruit Faster 

Author: Alberta Urban Garden

The video discusses how to prune tomatoes and take preventative measures to keep tomatoes healthy, productive, and disease free. 

How to Control Powdery Mildew with Milk 

Author: CaliKim 2 Garden & Home

Powdery mildew is a common garden fungal disease that can stunt the growth of your plants. This video explains how to control it using a simple milk spray.

Plant Disease Basics, ID, Management and Prevention

Printable Resources:

  • Resource Guide for Organic Insect and Disease Management: This guide from Cornell University, The Maine Organic Farmers and Gardeners Association, and New York State Integrated Pest Management Program gives an extensive overview of crop-specific pests and diseases accompanied by organic methods of management. Note that this resource is designed for farm-scale production so recommendations may not be ideal for the home garden. 

  • Key Vegetable Problems: This resource from UNH Extension describes some common vegetable problems for a variety of vegetable crops and recommendations for treatment

  • 10 Easy Steps to Prevent Common Garden Diseases: This resource from UNH Extension details a list of 10 simple steps you can take to prevent common garden diseases. Remember, prevention is the best avenue for keeping your plants healthy and disease-free.

Books: 

  • Bradley, F.M., Ellis, B.W., Martin, D.L., 2009. The Organic Gardener’s Handbook of natural insect and disease control. Rodale Press, New York, NY.

  • Homeyer, H. 2015. The New Hampshire gardener's companion: An Insider's guide to gardening in the granite state. (2nd ed). Rowman & Littlefield, Guilford, CT. 

Additional Crop/Disease-Specific Resources

Printable Resources:

  • Tomato Leaf Spots: This resource from UNH Extension describes how to diagnose Early Blight and Septoria Leaf Spots as well as treatment options.

  • Some Common Tomato Problems: This resource from UNH Extension discusses Blossom-End Rot and other tomato problems such as cracking and leaf curling.

Resources on Performing Plant Disease Tests

Below are links to plant diagnostics testing services from cooperative extension offices/universities in New England. For questions on how to collect samples for these tests, refer to your state's information and call your state's plant diagnostic lab with questions.

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