In the summertime, things start heating up in your outdoor worm composting bin. Unfortunately, if the bin temperature gets too high, the composting worms will overheat, dry out and die. There are many things you can do to keep your worm population cool enough to survive.
Placing the worm bin in the right location is the most important way to control the internal temperature. Exposure to the sun heats the bin up more quickly than you might think. So keeping your bin out of the sun will keep the temperature down.
Pick a spot that is shady for the entire day. Try placing it under an awning or shed roof, under a shady tree or next to tall bushes. Just don’t place it right up against the house, or local vermin might get the wrong idea and start muscling in on your home. Depending on the type of bin, you may need to provide shelter from the rain. Certain types of bin take on too much water. This drowns the worms and makes the bin moldy.
A dried-out worm bin is a sign of overheating – and it can quickly kill off the worms. Keeping the moisture level up is crucial in the hot summer months. If your composter has a lid, keep it on. The bedding should feel like a wrung-out sponge when you squeeze it. If it seems dry, spray a little water on top, but don’t flood it or your worms will be gasping for air. In the hot months, a burlap sack, landscaping cloth, or a sheet of moist newspapers can be placed on top of the bedding to reduce evaporation.
Extra bedding helps regulate bin temperature. The colder temperatures at night will last longer, reducing the risk of mid-day overheating. More bedding lets the worms dig deeper, away from the hotter top of the bin. Limit the amount of worm castings you harvest, or add more bedding (such as coconut coir, pure peat moss or shredded paper). If you have a tray-based worm composting system, such as the Worm Factory 360, use fewer trays and let the bedding accumulate.
The worms may decide that conditions are perfect for reproduction. Suddenly, you may see tiny brown specks – these are eggs. Soon afterward, hundreds or thousands of little baby worms appear. You can let the population control itself, or you can remove some of them. Release some into the yard, give them to friends, or start a new bin.
Unwanted creatures might show up in your bin, especially when it’s warm. If you see sprouts, pull them out. If ants set up a nursery, take the lid off and they will move it. Discourage bugs by cutting up scraps, burying food, and keeping the lid on. Don’t worry too much if you see some bugs in there, because they help break down the scraps. Read this article if millipedes, centipedes or mites show up. If raccoons make nocturnal visits, try using a bungee cord or bricks to keep the lid on.
If you get desperate, freeze the scraps in a small amount of water. At feeding time, place the scrap-sicle a hole in the center of the bin, covered in bedding. This will slowly cool off the worm bin as it melts, and leave scraps for the worm to enjoy later.
Keeping your worm bin happy and healthy in the summer months is mostly common sense. Protect the worm bin from the heat of the sun, and reduce evaporation by keeping the lid on. Any more that you do for your bin is a bonus. A productive worm bin will quickly break down kitchen and gardening scraps. This reduces trash problems. The resulting finished compost makes perfect fertilizer for your garden. A little protection goes as long way toward successful summer composting.