Blue Worm

 (Perionyx Excavatus)

Blue worms are sometimes called the Malaysian blue or Indian blue and are already in use by vermicomposters in Asia, Australia, and other tropical regions. This little composting worm can be identified by its blue sheen that's visible when brought into the light. Blue worms are beginning to make inroads into North America as more and more vermicomposter look for the ultimate composting worm.

Blue worms are small; typically growing to no more than 3 inches and are even thinner than red worms. So worm farmers that want their worms to pull double duty as composters and bait worms may want to stick to red worms, or the larger European Night Crawler.  

The blue worm is surrounded by some controversy in North America and has it's detractors. However we think this has more to do with how the worm is being sold, not it's actual performance. A quick search of the web will reveal many disappointed customers of some of the large on line worm retailers. These folks ordered up red worms only to find out that a large portion of the delivered worms were actually blue worms.

Unfortunately they realized this only after their worms started to die, or escaped their outdoor bins, mostly because the blues could not tolerate the environments red worms can. These are simply cases of the wrong worm in the wrong conditions. But that’s no consolation to those unfortunate customers who wasted their time and money; the blame is squarely at the feet of the retailer.

Blue worms will "invade" outdoor worm bins when released outdoors. This poses a problem for worm farmers that want to sell 100% red worms to their customers that want the more resiliant red worm . It also creates a problem for worm farmers that want to sell bait worms. Blue worms will not reach the size needed for good bait worms, but they will eat the bedding and food provided to bait worms in outdoor trenches.    

All things considered we think that the beginning worm farmer has better choices than the blue worm. However for the experienced worm composter that understands the blue worm they are an attractive option.  

Advantages of Blue Worm   

Blue worms possess many of the same traits as red worms; in fact they are often mistaken for red worms. Naturally they make good composting worms, but only under the right conditions. They have good appetites and breed quickly. One trait they do not share with red worms is the ability to withstand temperature and environment extremes.  

Blue worms like to live in bedding alongside their food source, or right below it. Like all top feeders they live off decaying vegetative organic matter, usually vegetables, fruit, garden scraps, and aged animal manure.  

Blue worms have a really big appetite which makes them very suitable for producing worm castings (a.k.a. worm poop). This breed does not get as large as Red worms, yet they will eat just as much.  

Like all good composting worms blue worms like living in close quarters colonies. This also makes them fast breeders; so many worm farmers think they are an ideal breed for composting. Unfortunately we don't know of any way to really plump up blues for use as bait worms. However they would make an interesting challenge for pet reptiles if used as feed worms.  

Blue worms reproduce very quickly. Once hatched they become sexually mature and able breed in less than two months. In ideal conditions mature blue worms produce nearly 19 cocoons a week with one hatchling emerging from each. These are just basic guidelines and many factors influence reproduction rates. Those factors include food sources, temperature, and moisture conditions.  

Blue worms do best in temperatures between 70 F to 80 F (21 C - 26 C). The University of Hawaii reports that blue worms can survive temperatures down to 45 F; however we don’t recommend pushing that lower limit if you have invested lots of money in blue worms. That being said we still don’t think cold tolerance is a strong suit of the blue worm. If you raise them in tropic climates you should have no problems. However if you worm farm in northern regions blue worms will die off if kept outside, unless you have a way of heating their bins.  

Despite their tropical origin it's a good idea to make sure your blue worms are protected from the sun and are provided ample shade if the temperature gets into the nineties. Blue worms have a propensity for fleeing their bins if conditions are not to their liking. We are not talking about a dozen worms crawling from the bin; we mean hundreds at a time escaping their beds.  

Some worm farmers say that Blue Worms like a drier environment than red worms. We have plenty of blue worms that unintentionally ended up in our indoor bins. A major worm distributor claimed they would send us 100% red worms, in reality they gave us about 20% blues. Our beds are moistened to optimize the growth and breeding of red worms, yet our blues flourish just fine in this moisture level. It’s our recommendation that for blues you start out with moisture levels similar to red worms.

Maintaining this moisture level in your bins also facilitates the breakdown of bedding and vegetative matter by the microbes found naturally in worm beds. Remember it is the mushy food and microbe mix that worms eat.  

Blue Worm Food  

Blue worms are extremely effective at composting left over fruit and vegetables, and garden waste. Blues are simple to feed. Simply bury small pockets of food in their bedding material. We will outline what you should feed, and what you should not feed your blues. This list is not all inclusive but merely a starting point. Learn more about feeding worms here.  

Do Feed:  

· Fruit Waste - Non Citrus (Apples, grapes, bananas, plums, peaches, pumpkin)  

· Vegetable Waste (carrots, lettuce, beans, peas, limited amounts of potatoes, leaf vegetables)  

· Egg shells - In moderation and best when crushed up a bit.  

· Coffee Grounds (Filters too) - An excellent worm food, but again in moderation  

· Tree leaves - Yes in moderation, stick to common species, avoid exotic tree leaves  

· Cardboard - Yes, shredded cardboard doubles as food and bedding.  

· Garden Waste - Bean stalks, pea vines, beet tops,  

· Starchy- Yes in moderations (Pasta, potatoes, rice, grains)  

· Aged animal manure - Yes, it's best to stick with horse manure in the beginning.  

· Commercial worm food, (Worm Chow etc...) Just start sparingly  

Do Not Feed:  

· Citrus fruit  

· Meat products  

· Dairy waste  

· Cooking oil or grease  

· Human waste  

· Pet waste  

If blue worms seem right for you find a good (quality) supplier and go from there.  

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