How to Amend Soil With Charcoal

Test your soil using a home test kit, following the instructions on your kit. Charcoal should only be added to soil when you need to raise the pH or if your soil has a specific mineral deficiency in potassium. As an alternative to running the test yourself, have your soil tested by a lab that offers soil testing.

Get charcoal. To avoid adding chemicals to your garden, look for ash that is from lump charcoal, or purchase charcoal and burn your own.

Turn over the soil in preparation for adding the charcoal ash.

Dig down 12 inches below the soil surface, turning over the soil. Remove rocks, sticks and other debris. Break apart soil clumps with your shovel. Move the soil out of the garden bed to create a trench of loose, debris-free soil.

Add your ash, making an even layer across the bottom of the trench. Use no more than 1 lb. ash for a 50 square foot garden bed.

Push half of the soil back over the ash.

Mix the soil and ash together so the charcoal ash is evenly distributed in the garden bed.

Fill in the rest of the bed with soil and again mix the soil to thoroughly distribute the ash.