There’s an almost endless array of materials that are suitable for compost.  In fact, some gardeners become so enthusiastic about composting that they want to toss everything in sight onto that delightfully rotting heap.  However, certain items will cause problems and can even be hazardous to your garden’s health.  Here are some commonplace materials that should never go into the compost pile.

Diseased plants

A working compost pile usually heats up enough to kill weed seeds, but disease organisms are another matter entirely.  The bacteria or fungi from diseased plants can easily survive the composting process.  If you then spread the compost on your garden, you will be spreading disease at the same time.  That would spell disaster.

Any plants stricken by mildew, bacterial leaf spot, blight, dry rot, or other diseases should be disposed of in the garbage.  You may also burn the material if you have a way to do so.  The remaining ashes will be safe and can be added to the compost pile.

Nonbiodegradable items

The compost bin is not a garbage can!  Don’t let anyone put plastic, glass, aluminum, synthetic or other nonbiodegradable items into the compost.  Although these items may not do any particular harm, they won’t decompose with the organic matter.  And nobody wants trash to wind up in their garden.

Mud, sand, gravel, or poor quality soil

Some people think that adding these bulky materials will increase the volume of finished compost.  However, such items contribute nothing, since they have no nutrients or useful bacterial value.  The only soil that should go into compost is good quality loam or humus.

Pet litter and droppings

Unused cat litter is acceptable in the compost.  But never put used cat litter, dog feces, or any type of pet droppings into the pile.  This material may contain dangerous organisms and parasites that will survive the composting process.

Toxic chemicals

First, don’t use plant debris that has been treated with weed killer or other chemicals, because traces will remain in the finished product.  Second, don’t put insecticides or poison into the compost in an attempt to keep insects and animals out.  All you’ll do is kill the beneficial organisms that are making the compost.  There are much better ways to keep flies and animals away from the decomposing heap.

Generally speaking, the more different ingredients that go into compost, the better the end result will be.  However, it’s important to understand that some items have no place in your compost pile.  Be careful to keep hazardous and nonbiodegradable materials out.  Only safe organic matter that will rot in a reasonable amount of time should be used.  Then you can be confident of making good quality, nutrient-rich compost that will benefit your garden.