Then she moved on to shredded junk mail and cardboard and I was given a really nifty composting bin and asked to leave the workshop before she got to kitchen scraps.īack to Jim. Then we got to leaves and I said 'of course you mean shredded leaves, as whole leaves mat down and stop the composting process'. When the woman teaching the class said to include grass clippings, 'I raised my hand and asked, 'don't you mean clippings from a lawn that hasn't been treated with herbicides?' She seemed puzzled, and then I explained the dangers of clippings from a treated lawn while my friend repeatedly elbowed me in the ribs. My friend made me promise to behave and I lied that I would. Same with composting classes held by well-meaning Extension Agents and/or their Master Gardener volunteers, who are often just passing along old information without thinking much about it.Įxample: A few years back I accompanied a friend to a composting class at a large and prestigious University in Philadelphia that was not Temple or Drexel (nor St Joe's or Villanova which are outside the city proper). Many (perhaps most) books on composting include grass clippings as an acceptable raw ingredient, along with shredded junk mail which is just stupid. It's also against the law in these states to use a fertilizer that is higher than ten percent nitrogen again, to try and protect the Bay.Īs I travel around the country, I see more and more municipal composting sites that have been burned and now have big warning signs posted: No grass clippings!īut I know I'm fighting an uphill battle. Lawns don't need potassium or phosphorus and fertilizers that contain phosphorus are banned in many areas, including the states of Virginia and Maryland, where the phosphorus ban is designed to help clean up the priceless Chesapeake Bay. Those clippings are ten percent nitrogen, and ten percent nitrogen is THE perfect lawn food. Either way is wrong, even if the lawn is not treated with chemical herbicides, because clippings belong ON the lawn. Now, it's a little hard to figure out whether you used your clippings to make compost or if you used them to mulch your dead tomatoes. It had killed plants at a level so low its almost unimaginable. Then one of them said: 'we tested for resides at the parts per million level. All the plants died, which confused the composters as they had had the finished compost tested and there was no evidence of herbicide residue. This was first reported decades ago by a University that made their own compost and used it to feed the bedding plants they were raising for their annual Spring plant sale. The reason for this is that some chemical herbicides are so persistent they survive the composting process and remain active enough to kill non-grass plants. If you still have the bag, it should contain a specific warning not to compost the clippings. The 'weed' part of the notorious 'weed and feed' is, of course, a chemical herbicide specifically one designed to kill any plant other than turf grass. Now that we're in the middle of lawn mowing season, your loss may save many other gardens from a similar fate. Is there any way I can dilute the wilting effects this contaminated soil has caused on my tomato plants? And if I can harvest any tomatoes from these plants, is the fruit safe to eat? And am I the only person this has happened to?'Ī. Now I have learned the difficulties of growing vegetables in this soilthe hard way. Jim in Gilbertsville PA writes: 'I used soil mulched from grass clippings from my lawn which is treated with common weed & feed.

Grass clippings in garden