That price sounds almost too good to be true. Someone will probably post with more accurate numbers. But for now, in case they don't, two cups should make a very generous 5 gallon bucket. Be sure to use rain water or water that has sat for a day to have the cholorine leave.

I am wondering in you are in America? Different parts of America and different countries have different materials available to fertalize a garden. Can you collect compost materials from kitchen scraps or leaves? Manure from caged rabbits?

I recommend you get some worms and start vermicomposting. You will need many of those bags to organically fertilize an acre garden. Start vermicomposting now for next years garden.

I make aereated teas with a 4 port aquarium pump. I use a double handful per gallon when I measure. Usually just dump some in as I have plenty. I add molasses and sometimes fish and kelp juice I buy.In 24-36 hours it froths up and I foliar feed/soil drench immediately.
I also top-dress around the base of plants. I add about 2" mix a little and water it in.
I used sifted castings as a starting medium for my bean and lettuce this year with amazing results. I prepped the soil, made a 2" "V" grove and filled with castings. I then pushed the bean seeds into it. Nearly 100% germination and huge, healty bean plants. I use no other fertilizers.

I sold some sifted castings on craigslist for $20/cu' and they weighed 40 lbs. If you have a cu' that only weighs 20lbs, it must be very dry. I don't think it is as good after it is dried out too much.

Get to wormin'!!! :) Good luck, Pete

Am really unsure whether microbes can be brought back to life after they have dried out. Anyone know? I also have doubts about the viability of bags of worm castings bought at a garden center which have been sitting out in the hot sun. The mineral content wouldn't be effected, but......

Microbes won't be completely killed off by soil or compost drying out. Fungi and some bacteria go into a spore stage, while other bacteria go dormant, awaiting more favorable conditions. But for sure a bag of compost sitting out in the hot sun all day (and doesn't have a moisture seal) is going to have less microbial life than one still moist and kept in the shade.

Last year, I ordered abt 20000 red worms--- it was already hot, in late spring. I put in a big plastic crate with a whole bunch of holes---like dozens on the bottom and dozens on the top. Put fiberglass screen on the bottom to prevent escape. The bedding was moist aged horse manure. Put in the shade outside. The next day I opened lid, and every one of them had come to the surface and died. I think it got too hot! Summer temps here run 100+ deg. for many days. Last week it hit 111 deg. in the shade. So I am very discouraged about trying to raise worms again. Do you keep them in a pit in the ground? I hear some people actually put them in a pantry or closet in the house to keep them cool....don't know if the wife would go for that ;-) Having a worm farm is a GREAT idea...but I don't know if I can keep them alive and thriving in hotter-than-hell S. Texas.
Thanks...I will be leery of buying such light/dry worm castings! Saves a lot on the shipping, but I'd rather have fresh stuff!

I use all outdoor open-bottom wormbeds. I also live where I wear a sweatshirt in the summer! :)

A pit should work. No bottom so they CAN escape rather than die if conditions are bad. Shady area with a heavy cover.

Check out sierrawormsolutions.com. They vermicompost in Reno which is hot/dry in the summer and cold in the winter. I like their cinderblock beds. Lots of helpful videos.

Mendopete, you are an inspiration! I lost tons of worms in the heat, and one bin was earthworms I'd hoped to use for fishing. Even here, in the heat, I have a really good spot. When they save themselves by diving down, do they ever return, or would I have to wait for eggs left behind, when conditions are good?