Compost sieves help to answer the question of when the compost is ready. This after all is a complicated term for compost. In theory one can simply spread organic waste over the ground and let it rot. This tends to take time and be a mess, possibly an unhealthy one.

We try to make compost to be dark colored, rich smelling and crumbly in texture by rotting organic matter under controlled conditions. However, not all organic matter is created equal. Broccoli stalks, for example, are going to be evident in the compost pile long after the potato peels are indistinguishable from the rest of the compost pile. Choices need to be made. Should one leave the compost to work for another two, three or six weeks or months? Should one use the compost with the unresolved matter in it, hoping to bury it out of sight? Or should one separate the compost, using the finished material and sending the uncomposted matter back to the next pile for more decomposition?

The solution to the separation is a sieve or sifter. I find that a 2" mesh allows the finished material to fall through while uncomposted stuff like broccoli stalks, twigs and mango pits get held back for another run through the pile. Some material like grasses get caught up in the strands and I return them to the pile as well under the assumption that any such debris will fall apart over the strands if it is sufficiently composted for use. I am sure that some small material that is not yet composted makes its way through, but, as I have already had it in three or more hot piles, I trust that it will add texture to the soil without difficulty.

My sieve is made of 1x3 common lumber with sides about 31" long to fit over my garden cart. The ends are about 18". There are no crucial measurements here as long as it fits over your cart or wheel barrow. I drilled 3/16" holes 2" apart around the sides and then strung it with 1/8" nylon cord using a simple over under weave. That is it.

To use it, place the sieve on top of your wheel barrow or cart and add compost to it with a fork. Using either the fork or your hand, move the compost over the sieve letting the smaller material fall through. Throw anything left in the sieve back on the pile. Keep your eyes open for material that should not be there in the first place like plastic thrown in the wrong place and remove it for recycling or disposal elsewhere.

The sieve is easily repaired and lasts for ages. It will make your composting life a little faster and easier and your plants will love you for it.