I’ve had a couple worm bins going for a year or so, mainly raising red wigglers along with a few night crawlers. The red wigglers have mainly been used just for composting although this year I have enough I’ll be using them for fishing, too. I usually just throw in a few night crawlers for an easy place to keep them on hand.
The bins have cycled through productivity and decline as I maintain and neglect them. In the last couple months I’ve made a point of keeping up with the worms and I’ve seen the population skyrocket as a result. In the past couple weeks, though, tiny white bugs showed up in the bins. With a little research I determined the little critters to be mites. Apparently harmless, but a little disconcerting, nonetheless. The mites – and occasional fruit fly outbreaks – seem to be a result of too much moisture and overfeeding.
Since we’re snowed in today the kids and I decided to remedy the problem by draining the extra water and mixing in some paper to soak up the moisture. That gave me a chance to take a couple pictures and give a bit of a description of how the bins are made.
The worm farm is made with Rubbermaid bins from Walmart. They’re about $10 a piece, durable, and seem to be one of the storage container products that doesn’t change every year so it should be easy enough to find more bins to add to the system in the future.
The idea is pretty simple. Start with a bin on the bottom to collect drainage from the worms. Some people drill a hole and install a valve to make draining the “worm tea” easier. I haven’t done that yet since it’s rare that I actually drain the tea. I set a couple bricks in the bottom of the bin to help support the next bin. It probably isn’t necessary with these bins but it gives me a little more peace of mind.
The next bin has a bunch of 1/4 inch holes drilled in the bottom. Again, there are different ideas on this. The drain holes aren’t needed but they make regulating the moisture a little easier. Personally, I like to have them. This bin has a lid with holes drilled in it for ventilation. Don’t worry about worms escaping. If you keep them happy they won’t want to leave. Besides, they’re photophobic and will avoid light whenever possible. Anyone who’s ever hunted night crawlers with a flashlight has seen that first hand.
Worms are incredibly efficient at breaking down food scraps so it takes a long time for a bin to fill up. When it eventually does, just set another bin with drain holes in the bottom on top of the full bin and start adding food. The worms will migrate into the new bin. After a few weeks, remove the old bin and add the nutrient rich worm castings to your garden. There will probably still be a handful of worms in the old bin but not enough to be concerned about.
If you have the problem that I had of the bin being too wet or having mites or fruit flies, try mixing in some shredded newspaper, cardboard (not the glossy or colored pages) or oatmeal to soak up the moisture. Keeping shredded paper on top seems to help regulate the water content by wicking moisture up and speeding evaporation while keep things from getting too dry.