Chemically Treated Grass Clippings in Compost Pile

Two years ago we accidentally added grass clippings from our chemically treated lawn to our compost bin. When we used the compost, all our plants died. The same thing happened again this spring. It couldn't just be the grass clippings. Are there other items we shouldn't add to compost?

What you put in your compost can influence the speed of decomposition and quality of compost produced.  Treated clippings are best left on the lawn.  They add nutrients and moisture to the soil. Avoid adding black walnut twigs, leaves and fruits.  These contain juglone that is toxic to other plants.  Once these materials are fully decomposed they are no longer toxic to other plants.  Partially decomposed compost can temporarily tie up nitrogen in the garden soil.  Mix this into gardens in the fall or wait for the compost to completely decompose (crumbly and brown like soil) before adding it to the garden.  Do not add meat or animal products to compost bins.  These materials can attract rodents.

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