• Maximum reproduction under ideal conditions: 3.8 cocoons per adult per week; 83.2% hatching success rate; 3.3 hatchlings per cocoon.  Net reproduction of 10.4 young per adult per week. Under ideal conditions, can double in population every 90 days.
• Maximum growth rate under ideal conditions: 32-73 days to cocoon hatch;  53-76 days to sexual maturity; 85-149 days from egg to maturity.
• Temperature requirements (°F): Minimum 38°, Maximum 95°, Ideal range 70-80°
• A sexually mature worm will have bands’ and this band or ring is referred to as the clitellum. Each worm changes sex many times, but they are not self fertile. When two worms mate, they each go off and deposit egg capsules containing up to 20 young. The average survival rate is between three and four per capsule. The newly deposited egg will look like a small lemon, and be pale in color; as the blood supply increases, the color will deepen, and can be almost black before hatching

• Surface (epigeic) worms.  Live primarily in the top few inches, eating garbage, leaves, and all sorts of organic debris. They handle crowding well and are the most conventional composting worms. The most popular type is the red worm, also known as Eisenia Fetida.  Other types, such as European Crawler (Eisenia Hortensis) are larger, a little more darker brown, and make good  fishing worms, but they are more prone to wandering if their habitat is not suitable.  P. Excavatus a.k.a. blue worm, is a native worm to the Southeasten United States, and although it has a high reproduction rate and is a great composter, it does not tolerate low temperatures.  It too is prone to wandering.  Another compost worm is the African nightcrawler (Eudrilus Eugenia)

This is the most common type of worm bin.  Levels are stacked and have screened bottoms which allow the passage of worms between levels. The levels can be at various age levels such

that once a given level is finished composting, the worms will pass to other levels (usually not) and the castings harvested.  This usually requires the removal of worms via  various means.

2.      Flow- Through System, Reactors

There are no layers or tiers in this system, but worms move upward as food is expended, thus allowing the bottom section to mature and be harvested. Vermicompost and castings are harvested directly from the bottom via means of bars, screens, and various mechanisms (depending on design). There are some problems with “messiness” and drying out as the bottom remains open.

3.       Outdoor Worm Pits

Outdoor worm pits range from boxes buried in the ground to pits dug in shaded areas.  I have personally had great success with the latter, as native composting worms such as P. Excavatus move in for a feast.

4.      Commercial Systems

Commercial systems are beyond the scope of this guide but they include outdoor windrow systems and large flow through reactors.

Worm Windrow

Large Worm Farm Flow Reactor

• Plant- based kitchen scraps (fruits, veggies, etc). Chop larger pieces if possible.
• Tea bags, used coffee and filters.
• Shredded un-glossed paper or cardboard products that don’t have colored inks (unless soy based).
• Egg shells. Crush as small as possible.
• Avoid all meat and oil based foods.
• Leaves and yard maintenance items. Try and avoid oak leaves, and do not use any plant materials which have been treated with chemicals. Do not use large amounts of “greens” such as grass clippings without composting them first (as they will heat the bin).
• Manure is one of the best foods possible. However, most “hot” manures will need to sit for a couple of weeks or be composted first. Some manures, like rabbit manure, can be added immediately.
• Do not let food scrapes become rancid before giving to worms. Anaerobic (without air) processes can produce ammonia and other harmful substances to the worms.  Some folks chop up and preserve food scraps in the freezer. However, if you are concerned about energy costs, you might try to place your extra foods in a conventional composter (or pile) as an alternative before feeding to worms.
• Strive for a good balance of “greens” and “browns.”

1.    Temperature control.  Do not overfeed so as not to overheat bin. Red worms can tolerate lows into the 40’s and highs into the 90’s, but optimal growth and reproduction take place between the 70s and 80s. If bin is overheated, remove excess food, and mist bed to increase evaporative cooling (you can take top off and place damp cardboard or burlap on top). Alternately, if you can bring bin inside during heat, do so (and of course, leave in full shade while outdoors).  Feeding worms frozen food scraps from the freezer is a great way to cool down the bin! In cold weather, keep bin covered, move indoors, and/or move into sunlight. Adding more food in cold temps will generate more heat in bin!

2.    PH – After awhile, the ph may drop due to buildup of acids from foods. A modest application of garden lime or crushed egg shells can raise ph as needed. Limit the use of too many acidic foods such as tomatoes, citrus, etc. These are fine to use in moderation, but be aware of the above.

3.   Moisture – The bedding should have a moisture content about like a well wrung out cloth/towel.  Most of the moisture will come from the foods themselves, and it should not be necessary to add water. However, if the moisture level dries out, be sure to not add chlorinated water. The residue coming from the bottom is known as leachate, and one way to know if the moisture level of the bin is right is if the leachate acts like it wants to ooze out but doesn’t quite drip etc. DO NOT let the worm bin dry out or your worms will die.  Er on the side of being too wet than too dry.

4.     Bugs and pests – most of these are more of a nuisance to humans that to the worms. Ants will occasionally build nests in outdoors bins, but can be discouraged by not allowing beds to get dry.  Ants do not harm the worms. With extreme infestations, suitable insecticides can be placed around the legs of bins (avoid contact with bed!). Most insects are not dangerous to worms and in fact, can actually aid in composting!  The Black Soldier Fly Larvae (BSFL) is just one such beneficial companion composter. If you have an overabundance of mites you are probably overfeeding and/or the bed is too wet.  As mentioned, fruit flies can be discouraged by not overfeeding and by burying foods.

5.    Odors – There should be very little odor in a properly operating bin.  This is usually a problem of using the wrong foods, overfeeding, insufficient aeration and not burying the foods.

6.   Handling – Minimize the direct handling of worms because skin oils can affect their protective coating. Do not over dig or otherwise over disturb the bed – though this is fine (and necessary) in moderation.

7.   Reproduction Rate – If it is desirable to increase numbers, then over crowding must be avoided as worms can sense the need to reduce or increase their population based on available space. Therefore, if more worms are desired, and the bin is getting full, it may be necessary to offload some worms to a new bin. A happy medium of worm population density should be sought however, because worms also reproduce based on their frequency of bumping into one another. When the bin gets over crowded, the worms will loose their ‘clitellum’ center band.  Seeing this absent on many worms, is a sign that its time to separate into a new bin.

Worm Castings

Following is a description of the process to make use of your worm castings and vermicompost.

• Once completed, castings or vermicompost are collected, it is always advisable to first separate any remaining worms or cocoons. These can be removed out by hand (wear gloves) or by a variety of other methods easily researched (separation via light, etc).
• If there are larger particles that have not been broken down, it is advisable to shake the castings through a screen (1/2” or 1/4” depending on the particle size you wish).
• For soil medium enhancements, pure castings should be used at around 10-20% of the mixture. A little goes a long way, and too much is less effective. Handfuls of castings and vermicompost can also be applied as needed around the base of plants, covering turf, etc.
• Compost tea.  “Leachate” which is runoff from the worm bin, is non-broken down organic matter and as such, contains many anaerobic bacteria. These can produce some undesirable by products for your plants. Castings tea is made by adding water to finished castings, and it is far healthier for plants, having a good mixture of micro-organisms and nutrients. These micro-organism populations can be further enhanced by injecting air and adding sugars (like molasses) for a day or so. This however, is not necessary and the castings tea can simply be made by adding water and applying directly to plant roots, or as a foliar spray.