Harvesting provides you with bulk red worms to sell, vermicompost for garden use, castings for fertilizer or worm tea, and egg capsules to start an indoor compost.
I. Table harvesting:
This method is the most hands on type of harvesting. As you can see you start with a large pile of compost in the sun or under a light. This will drive your red worms down to the bottom while you slowly remove the compost. You can separate the Vermicompost and egg capsules while you are clearing off the table.
Don't be afraid to take a break and do something else in between. Your red worms will continue to move down into the pile even while you are gone. Just don't forget about them and let them over heat. Before you know it your pile is small and you start to run into a mass of red worms squirming to evade the light. You can pretty much remove all of the debris, but this is not recommended if you just want to put the red worms back into your compost. This can cause a lot of stress. A good idea for your first break is to make sure your compost bin is made ready for the return of your red worms when you are done.
This type of harvesting is great for harvesting red worms, but to get castings a screen method may be best.
II. Screen Harvesting:
The harvester being shown above is for small scale compost. See all the harvesters on the compost and other products page. I used a 1/4" screen to allow the majority of finished vermicompost through the screen. Due to the size of screen all of the egg capsules also fell into the finished compost. To get a higher percentage of castings and less Vermicompost use a 1/8" screen, this will also limit the amount of egg capsules falling through.
Screens are very hard to use when your compost is too wet. Most of your compost will clump and roll out the end. Your redworms will survive the screen process, but they will be a little battered.
When you use a screen to harvest with you end up with a very uniform, soft and fluffy mixture ready to use. There are larger scale screen harvesters that have motors and there are square screens that fit right over a wheel barrel. The all work some are more labor intensive.
If you have a cedar bin with the screen divider you can temporarily remove it from the compost bin and use it for sifting.
This is the black gold that you can achieve from Vermicomposting.