Harvesting your wormcastings   
Harvesting your wormcastings  :
There are Several methods of separating your worms from the wormcastings :
Light refraction method :             suitable for small units
Starvation method          :             for small to medium wormgrowers
Mechanical removal       :             for the large wormgrower

Light refraction  :
The principle here is, that worms are sensitive to light.                                  
Even although they are blind, they still feel light falling on them.
We use that instinct for separating the worms out of our wormcastings.
Work on  a long table; put the wormcastings plus worms in the middle in a long row, and then you will see the worms disappearing into the
wormcastings in  a hurry to get away from the light.
The reason we use a long table, is, that you can work continuously around it, and do not have to wait for the worms to disappear
as you remove the wormcastings over te edge of the table into say a wheelbarrow or a box under the edge.
Use a small hand rake, or chop sticks to draw the castings from the top of the heap to the edge, if you accidently uncover some worms,
you may pick them up with a set of tweezers, (be careful not to damage them, gently does it ) and drop them into a receptacle.
If you are going to sell the worms, it is quite safe, to use a bowl of water, not to cold, not too warm, and you can put this bowl on a set of
scales, fill with water, and then reset to the “0” mark.
That way you will know the weight of the worms you have removed !
After removing all the worm castings, you will have a heap of wriggling worms, trying to get away from the light under each other.
You pick these up, with a pair of gloves, and ready them for sale or for putting back into the unit you are using.
We use a circular table, so that we can sit down on the job.                                                                       See the accompanying photos below.

If you are using large boxes to grow your worms, the light refracting job can be done, by lightly raking the top of the material in the box
to one side in a heap, and then gently remove the heap into buckets or boxes .                                               See photo at Mechanical removal.

In general, you will then still have some worms in your wormcastings, so you cannot guarantee your wormcastings to be free of worms
as you offer the castings for sale.
But it works very well if you have patience, and the wormboxes are reasonably dry to the touch.
If the material is wet, you will have to rake a bit deeper, and then keep turning over the top until it dries enough, to do the job.
The main advantage of this way of working, is, that you are not disturbing the worms overmuch,
as they are digging down to the bottom of the box as you work .
Because the worms stay in the box, you can recommence feeding when you have removed the wormcastings.
This is how you remove the castings after starving the worms.                                                                     See that method below.

Starvation method :
The priciple here is, that worms will eat practically 24 hours a day, and if there is no food available, they will adjust their body weight, and
if it takes too long for food to arrive, they will hibernate, go to rest.
But before that, you can safely starve the worms for about three weeks to a month.
Then when you commence feeding again, the worms will soon find out where the new foodsource is, usually within 48 hours, and will
travel there en masse.
Do not wait too long with collecting them when they are feeding well, because the whole exercise would collapse as the worms travel
away from the foodsource after a few days.
Just wait two or three days, and you will see a wriggling mass of worms under the food.
The best idea is, to put the food in small trays, so that you can lift the worms food and all out of your feeding box,
and transfer them to a new site, or sort them out of the food, but that is a bit messy !
This method is very suitable if you just want to shift the worms from one box to another.
You will not get them all, but the wormcastings are harvestable when you have removed the bulk of your worm population out of it.

Mechanical Harvesting :
This depends on the size of the wormfarm naturally, and how it is set up.
Some farms are housing the worms under a roof, then you can set up any type of harvesting, like above described.
If the farm is an open type, you genereally would have to shift the contents of the beds to your wormsorter system.
Here too, you could work in a shed and use a long table with strong lighting above it ( Light refraction ).
If you can use machinery like a front end loader, you can carefully pick up the bed, killing some worms in the process.

Setting out fresh food trays after starving the worms is a better idea, as you can then pick up the food trays with a loader,
and just shift the worms to a new site.

There are several ways of removing the wormcastings from the bottom of the feeding bed,
by having a gap at the bottom of the boxes, where you can use a raking out system,
some farmers have mechanised this with moving chains or augers.

There are rotating sorters on the market, where drums made of wire mesh screens are filled at one end,
and the different grades of wormcastings drop through the mazes of the wire mesh,
which has been designed in sections, starting fine mesh to large mesh at the other end.
Sticks and stones will drop out at the bottom of these machines.
The worms will travel along the whole route. and drop through here and there.
The method here is, to wait until the worms have shifted to fesh food.

What you do, is have the food in a windrow say a yard wide and two feet high.
Wait until the worms are starting to migrate because of food shortage,
and then build a new windrow of fresh foodstuff right beside the first one.
you can then pick up the wormcastings with a frontend loader from the previous windrow,
and run it through your sorting machine.

The best machinery we have seen, was a tractor drawn rotating drum being towed over the shallow feeding bed and the feed,
worms and all being shovelled into the drum as it travels along.
The drum has long stainless steel pins inside it, and the worms will cling to them as long as they can.
As the speed of rotation is slow, they will get too heavy to hold on when the drum gets to the top,
and the heavier mature worms will then drop down into a tray,
where they can be collected when the machine reaches the end of the windrow.
The unused food and wormcastings will drop out of the slightly tilted drum back into a windrow,
where it can be picked up with the frontend loader.
A second trailer can collect the wormcastings if desired.