Anyone involved with gardening knows about the importance of compost. When spread in your garden during appropriate times of the year, the compost enriches soil of all kinds of nutrients that ensure healthy plants and a healthy lawn.
All the nutrients are created during the interaction of rotting organic materials that include kitchen scraps, fruits, vegetables, fruit rinds, and all sorts of kitchen garbage that many who do not know about compost simply throw away.
Within days of the start of a batch compost pile, it begins to heat up. This is due to the interaction of the microbes that are part of the organic materials of the pile, moisture that is already present in the ground, and oxygen. The heating effect is the metabolic activity of the microbes including eating, excreting, breathing, and multiplying. Moreover, fungi and organisms in the soil on which the pile sits also become a part of the process.
Continuous compost piles, which are built slowly, over a long period of time does not heat up as much as the batch pile and this is why it takes so much longer for a continuous pile to decompose.
A properly made aerated static compost pile that is turned at the appropriate temperatures experience heating cycles. A compost thermometer is an essential tool that tells you when to turn the pile and assists in monitoring it as it passes through three distinct phases of development.
The first phase is called the mesophilic. This is when the pile reaches temperatures of 68°F to 104°F. The second phase is called the thermophilic when the pile reaches temperatures of 105°F to more than 150°F. The final phase is called maturation. This is when the pile does not reheat after being turned.
Use the compost thermometer to discover when the pile reaches the mesophilic phase and then turn it so that it can progress to the next stage. When it reaches the thermophilic stage turn it again so that it can progress to the maturation phase.
Compost thermometer.
(courtesy: Thomas Bowes at flickr.com)
To use compost to sterilize weed seeds and kill pathogens, monitor the pile with your compost thermometer to determine when it reaches a range of 140°F and 150°F for at least three to four days. Make sure that the pile does not reach a temperature above 150°F for more than a couple of hours because it will start killing beneficial microbes.
A good quality compost thermometer should have these characteristics:
· A length that can reach the center of the compost pile (about 12-inches to 14-inches long).
· A clear, easy to read display.
· Made of stainless steel or other non-rusting material.
· A temperature range of 0°F to 200°F
· A display that is hermetically sealed so that it won’t fog up.
· A warranty.
Here is how to use the compost thermometer.
· Grab the thermometer by the meter and thrust it into the center of the pile.
· Leave it in the pile until the meter stops moving.
· Read the temperature on the meter.
People who use a compost thermometer like to take three temperature readings at a time. They do this because it is possible that the thermometer is thrust into a low activity pocket of the pile causing a false reading.
Once a batch compost pile is built, it should heat up to 140°F or higher within 24 to 48-hours.
