microbes eat my garbage! Or something like that...
Saturday, December 13, 2008
Bokashi tip of the day: rough pH test
May seem like an odd time to post this, but 1) I just thought of it, and 2) Planting season is never too far off. Thankfully.
Most of the bokashi retailers recommend that you let planter-finishing units rest for two weeks before planting. This is because fresh or newly cured bokashi is still acidic enough that it may burn plant roots. This same acid concern lies behind the recommended distance between trenches and gardens or trees. And some vermicomposters prefer to let their bokashi cure awhile longer than the standard ten days to two weeks before feeding it to the worms, also for fear of acids.
How acid is too?
Well, if a pinch of baking soda added to a tablespoon of moist bokashi (or compost) fizzes, then it’s definitely too acidic for garden safety—less than 5 pH. I can’t recall offhand what the ideal pH for redworms, though I seem to remember it being at least slightly dependent on the species of worm, but certainly you shouldn’t add any fizzy bokashi to a wormery.
BTW, that test works for soil, too, and it’s possible to test for alkalinity almost as easily: Dig up a scant cup of garden soil. Pick out any bits of inert or living matter, comb for consistency, and let air-dry. Add several drops of vinegar to dried soil to test for alkalinity—fizzing means pH over 7.5. Moisten some of the dried soil with distilled water until it’s very damp but not sopping and add a pinch of baking soda to a tablespoon of soil to test for acidity.
For more precise measurements, litmus paper’s probably the cheapest option.