Three questions from Ursula:
1. How can I store worm castings for use later in the spring?
I already know you can’t let it dry out as it turns into
a cement like mix. I would like to preserve the beneficial
organisms without drowning or suffocating them.
2. When I make worm tea (1 cup to 1 gallon) for watering
house plants the castings accumulate on top and eventually
form a crust. Do I need to break this up?
3. Do those gray egg cartons which organic eggs are sold in
have any chemicals in them that may harm the worms?
I use the torn pieces for bedding but the worms have never
even nibbled them!
1) Storing worm castings is relatively straightforward – the main goal should be to store the material at a moisture content that’s dry enough that it doesn’t feel moist, but not so dry that it becomes crispy and lifeless. When you squeeze it in your hand it shouldn’t release water, but it should be able to partially hold its form (poking with your finger should easily break it apart though).
Using some sort of enclosed bin similar to a worm bin would likely work very well – it’s important to have air flow for the sake of keeping everything aerobic, but also some ability to maintain humidity (storing in a wooden box probably won’t work so well). Plastic bags would probably be fine as long as you added lots of tiny holes in the sides.
2) I’d be interested to learn about your worm tea making process – sounds like you might simply be dumping the vermicompost right in the water. My suggestion would be to submerge a permeable bag (cloth, nylon stocking etc) in the water so that most of the vermicompost can actually be removed afterward (i.e. you aren’t left with sludge in the bottom) and the tea itself doesn’t have much particulate material in it. If you are getting a crust on top of your soil this is perfectly fine but breaking it up and mixing it in with the soil a bit will likely be the best approach – it will be easier to water the plant, plus you will end up with more benefits from the material itself.
3) Excellent question – unfortunately I don’t really have a good answer for you. I can only share my own experiences in this department. Egg carton / drink tray cardboard is actually my favorite for vermicomposting systems. It is easy to tear up, holds water really well, and seems to break down fairly easily (in comparison to other cardboards etc). I have seen no evidence of harmful effects, and in fact, the worms always seem to thrive in systems when I use it. I’ve noticed that this type of cardboard (especially the drink trays, and the stuff used to pack electronics etc) can have a rather strong, almost vinegary odor to it, so I have little doubt that it contains some form of “chemical” – likely some sort of binding agent. My gut feeling is that it’s not really anything to be concerned with, however – again, the worms just seem to love the stuff, and will happily convert it into grayish worm turds over time.
That’s odd that you are not seeing any evidence of worm “nibbling” – perhaps they’re simply more interested in other materials you have in the bin?
Anyway – hope this helps, Ursula. Thanks for the great questions!