Photo: Stewardship Network

From the MN Stewardship Network - April 24, 2026

Many of us are planning our summer gardens and happily ordering seeds and plants. To avoid importing pathogens, pests, or weed seeds, it pays to follow these tips from The Minnesota Department of Agriculture’s podcast, “Smarty Plants.”

Anything we bring into our gardens is a potential pathway for pathogens and noxious weeds, such as fungi, bacteria, viruses, and nematodes. Reputable suppliers follow the rules on cleaning, testing, and proper labeling. Seed labels should include noxious weed seed content. So read the label!

Some pathogens can hide on the outside of the seed, and bacteria can even get inside the seed. These contaminated seeds don’t look any different than healthy seeds. Buying from a good, reputable company will help avoid this problem.

Seed libraries are also required to have seeds free of noxious weeds. Avoid buying or swapping older seeds, as they may have a lower germination rate.

Some of us like to try planting seeds from plants that have graced our dining tables. But plants imported or allowed in grocery stores may be healthy for humans but may have very small quantities of plant pathogens. Planting these seeds puts your garden at risk.

If you like to plant seeds from plants you’ve grown, start with seeds or plants from a reputable source. Choose a healthy plant on which the fruit looks healthy. If you want to swap, swap with local neighbors, because although there is still a risk of pathogens, they would be organisms that are already in our environment and would not be introducing anything new that adds extra problems to gardening.

Online deals that look too good to be true probably are. It can be hard to tell where the seed is from. Don't be afraid to use the customer service option to ask for more information.

If you want to try a plant that may be contaminated, keep it in a pot or a contained area to see how it looks when it grows.

If you find what you suspect is a pathogen, report it to the Minnesota Department of Agriculture. Report a Plant, Pest, Disease Report a Pest | Minnesota Department of Agriculture

The following resources can be very helpful: What's wrong with my plant? : Garden : University of Minnesota Extension and UMN Plant Disease Clinic | Plant Disease Clinic.