In the last two years I have abandoned the tray-type worm bins as illustrated in Compost Tea Making. They work, but they’re fussy in regards to temperature, moisture and food. However, for those worm growers with limited space they are still a viable option. One has to take care that the trays do not dry out, become too hot in the sun, or propagate mold. The upside is that if one performs the ritual judiciously, perfect smooth worm castings can be produced.
Now, I use two 40 gallon bins that I alternate with cow pies and kitchen scraps, as well as a 4 to 5 yard pile of good manure that I bring in and seed with about ¼ yard of the previous years manure pile. There is always some manure + worms sitting in that large pile on a concrete slab. I protect the pile from birds and moles. I cannot protect it from little garter snakes eating the worms, but it is in the middle of a clear cow pasture, so resident Cooper hawks help in that regard.
Due to the presence of sawdust in much of the manure I get, the finished product is less than smooth, and quite sticky. Therefore, I hesitate to deem the product “worm castings”, rather a hybrid between year-aged manure and worm castings. It’s not clean enough for me to feel comfortable using it for compost tea. The product generally works well in the garden, but in too strong a concentration some plants suffer possibly due to the sticky factors association with less oxygen. That is a speculation at this time.
Out of the two smaller 40 gallon bins I can dig down and glean out some good clean castings for compost tea.
Any ideas worm growers?