Houzz Logo Print

pH question: charcoal as soil amendment

11 years ago

There appears to be some confusion about the effect of charcoal on the pH of the soil. Charcoal is generally alkaline to varying degrees, but a found some sources claiming that it can be used to LOWER the pH of the water used in Hydroponics!

The pH issue might not be a concern either way though, since very little charcoal in the soil still has a beneficial effect. One scholarly article I read claimed that just 1% charcoal by weight in the soil is enough to reap the benefits.

So here's my question: would adding charcoal to a soil at the rate of 1% really make it any more alkaline, even if the charcoal had a pH of 8 or 9?

I've already given up trying to use the ashes from my woodstove because of their caustic nature, but I started to sift out the softwood charcoal and am dying to use it in my homemade potting soil and in the garden. Visions of Amazonian Terra Prieta are float around my mind... :)

Thanks for any feedback.

Comments (68)

Preferred General Contracting, Inc.
Average rating: 4.7 out of 5 stars9 Reviews
Fairfax County's Specialized, Comprehensive Renovations Firm