of Composting
in a Northern California suburb
Word of the day: Chitinous
It is still crab season in Northern CA, with Dungeoness Crab going for about $6 a pound, cooked and cleaned.
In 5 days the pile has heated up to 126 degrees.
On day 6 the pile has heated up to 128 degrees, nearly to the Hot Zone - (perhaps I'll receive an award from the compost fairy?)
On to Day 7
Back to
I don't want to have a smelly pile. So I did some research and here is what I've learned:
Crab shell is a good fertilizer and substitute for bonemeal, due to it's high concentration of calcium, although it isn't so high in phosphorous. Tomatoes enjoy a healthy dose of crab shell due to it's high calcium content. Plants like Geraniums will like it as well.
Crab shell is also high in chitin, which is known to promote the growth of chitin eating bacteria when present. The exoskeletons of fungus and nematodes eggs, as well as the jaw structures of some garden pests like the japanese beetle grub are high in chitin. Crab shell, when added to the soil, helps create a hostile environment for the fungus and nematodes by feeding the biological life that eats the chitin based organisms. It is not classified as a fungicide or a nematocide even though it is known to have these properties.
The chitin in the crabshell stimulates soil organisms to secrete enzymes called chitinases. These enzymes degrade chitin, which is a component of flea egg shells. The presence of chitin in the soil makes it a natural biopesticide that is non-toxic to birds, animals, fish, and plants.
Just so happens that Japanese Beetle grubs and grubs in general, have jaws made of Chitin, which is dissolved by chitinase bacteria. So, not only is crab shell a good slow release fertilizer, it can kill off grubs, indirectly by feeding their enemies at the same time. .
Should I add crab shells to compost?
yes.
The chitin in the crab shells is wonderful in the garden since its presence causes the micro organisims to exude a chemical that prevents neomtodes. People who do this commercially kilm dry the crab shells, grind them into powder and sell it at garden stores. (And I was going to throw it away.)
Will adding crab shells make my pile smelly?
My advice is to bury it DEEP in the pile, to prevent any smell. It breaks down slowly. Best if you can grind it up first. I didn't.
On to Day 7