Design and Construction of My Worm Bin

Design and Construction of My Worm Bin

Materials and tools to construct:

Ten Gallon Sterilite plastic tote

Cheapest  1 inch X 3 inch strapping you can buy

Two inch diameter hole saw and electric drill to cut ventilation holes in sides and lid.

Fiber glass window screening to cover vents holes

GOOP adhesive to secure screening and plug holes

Flexible one inch putty knife to spread GOOP

Sand paper to smooth holes cut by hole saw

Lots of old news paper, don’t use the glossy inserts

Construction:

Use hole saw to cut two ventilation holes near the top of the tote on two sides – total of four two inch diameter vents

Cut two more holes in the lid.

Smooth the edges of holes with sand paper and use GOOP to glue fiber glass screening over all six vent holes.

Construct base to fit in the bottom of tote and cover with the fiberglass screen.  I use GOOP or Hot Melt Glue to hold the screen in place initially and then add tacks.

Plug the holes near the handles with GOOP.  A small piece of screen helps bridge the hole.

Why?

Ventilation and air circulation help reduce condensation inside the bin.  Getting rid of the moisture that is a byproduct of the vermiculture process is very important.  The vermiculture should stay moist and the castings should be crumbly – NOT muddy.  The air space under the base helps too. 

Worms need air to breath; they absorb oxygen through their skin.  And air promotes aerobic decomposition which is the “good” kind.  Anaerobic decomposition (without air) produces nasty smells.

Drain – I have eliminated the drain which came with the original bin.  It was there to drain off excess “tea” that accumulated in the space under the base.  The drain leaked.  Also I have changed my method of getting rid of the excess moisture which has eliminated the need for a drain.  In fact I am considering adding vents to the bottom of the bin to keep this area drier.

Base – to support the bedding and allow excess moisture to accumulate below the bedding.  Otherwise the bottom of the bin would get soggy wet and so would the vermiculture in that area.  Wet muddy vermiculture is to be avoided.  There is less air in this type of environment and can result in anaerobic (lacking oxygen) decomposition which smells awful.  We want aerobic (in the presence of oxygen) decomposition.

Fiberglass Screens over vents and all holes plugged – to keep resident fruit flies inside the bin until captured in the fly trap and to exclude visiting fruit flies that are attracted by the smell of good food. These visitors would lay their eggs if given a chance.  With the fly trap installed there will be few if any fruit flies inside the bin under normal conditions. (During my latest inspection on the inside of the eleven bins in my cellar I found one fruit fly.)