Undersized Vegetables
My squash, cucumber, beet and Swiss chard plants appear to be undersized. Five years ago we had a very large tree adjacent to the garden cut down. When I dig in the garden I still find roots. Could there be a problem with the soil because of the tree roots? Would a soil test tell me anything?
A soil test is always a helpful tool in establishing and managing a garden or landscape. Contact your local University Extension office. If the tree you removed was a black walnut, it could be the problem. All parts, including the roots or black walnuts contain juglone, a substance toxic to many plants. It can take 5 to 10 years for the roots to decompose and lose their toxicity. If this is the case – patience or moving the garden is the solution. If the tree wasn’t a black walnut the plants may be lacking nutrients temporary tied up during the decomposition of the old roots. A little additional nitrogen fertilizer will help compensate for this temporary shortage. Don’t overdo the nitrogen or you will have large plants with no roots or fruits to eat. Follow your soil test recommendations to improve the health and productivity of your garden.
Related
Upcoming Live Events
& Webinars
Jan. 28, 2026
FREE WEBINAR:
Past, Present & Future of Mitchell Park and its Conservatory, the Domes
Register here
Feb. 13 - 15, 2026
PBS Wisconsin
Garden & Green Living EXPO
Madison, WI
More information
Feb. 18, 2026
FREE WEBINAR:
Plants that Go the Distance
Register here
Feb. 25, 2026
FREE WEBINAR:
Flowering Houseplants
Register here
Mar. 5, 2026
FREE WEBINAR:
Start New Plants from Seeds, Cuttings and More
Register here
Mar. 11, 2026
FREE WEBINAR:
Save Money & Boost Your Growing Success with Bare Root Plants
Register here
Mar. 18, 2026
FREE WEBINAR:
Patio, Deck and Balcony Gardens
Register here
March 26, 2026
FREE WEBINAR:
Getting Started Growing Vegetable and Flower Gardens
Register here
April 1, 2026
FREE WEBINAR:
Growing a Bountiful Harvest
Register here
May 6, 2026
FREE WEBINAR:
Adding Native Plants
to Any Size Gardening Space
Register here
June 3, 2026
FREE WEBINAR:
Managing Your Landscape
with Pollinators in Mind
Register here
WATCH ON-DEMAND WEBINARS
Learn More


