Composting with worms is a good way to continue to make compost during the winter, when it's too cold to do so outdoors. This method allows you to make your own compost indoors, even in a city apartment. Worms need proper care and feeding, however, or problems like pests, unpleasant odors, or worms crawling out of the bin may occur. These can be remedied by maintaining correct conditions in the worm composting bin.
Conditions Are Too Dry
Worms may leave the bin if the bedding is too dry, or they may simply die in the bin. Bedding should feel like a moist, wrung-out sponge. Spray the contents of the bin lightly with water, and carefully stir it a little until it is evenly moist.
Conditions Are Too Wet
Worms will try to leave the bin if it is too wet, or if there is water standing in the bottom of the bin. If they are trapped in a wet bin, they will die. To remedy a soggy bin, carefully add more dry ingredients, or drain the water from the bin.
To drain a bin, drill some 3/16 inch holes in the bottom of the bin. Raise it on blocks over a tray to catch the water. Worms will not crawl through the holes if the moisture level and food supply are correct.
Conditions Are Too Acidic
Citrus peels are very acidic, and worms will not eat them; do not add them to the bin. Worms will leave the bin under high acid conditions. If the bedding in your bin tests high acid, mix in a small amount of agricultural lime to neutralize it. Retest until the acid level is between 6.4 and 6.9.
Not Enough Air
Compacted bedding or wet bedding limits the amount of oxygen available to worms. Inadequate aeration interferes with healthy microbial activity that is necessary for decomposition in the worm bin. Gently lift or turn some of the bedding when you bury food scraps, and it will help maintain a good air ratio in the bedding.
Pests and Odor
Pests and odor problems are usually caused by adding improper foods to your compost bin. Worms will not eat meats, fish, dairy, bones, grease, fat, oils and cooked rice or pasta. If these are added to your worm bin, they will cause unpleasant odors and may attract rats, roaches, and other pests. Too many fruit scraps may attract fruit flies; if this is a problem, reduce the amount the fruit you add.
Worms prefer temperatures between 50 and 75 degrees F. They will survive in warmer or cooler temperatures, but they will be sluggish. Try to maintain a temperature environment where they will be active. The best compost is made by active worms.