Corn ash is obtained from corn-burning heating systems. Corn burners use dried, clean-burning corn to produce heat; the corn leaves ash behind in the burners that must be cleaned out periodically. This ash has a high lime content and can be used in the garden to increase the alkalinity of the soil. Using corn ash as fertilizer is very simple. The ash's lime boost is valuable, natural option to increase productivity when growing plants that require a bit more lime in the soil, such as tomatoes. It's best to use corn ash fertilizer on a non-windy day because that makes it easier to spread.
Use a hand tiller to break up the soil in the garden plot, removing any large rocks, roots and plant remains. This will allow you to really work the corn ash into the soil.
Smooth out the top of the plot with a garden rake.
Sprinkle an even layer of corn ash fertilizer on top of the loosened dirt. The corn ash layer should be no more than an inch thick. It will be very fine and light, so you may want to crouch down near the ground to scatter the corn ash. This will keep it from blowing back up in your face.
Rake the corn ash into the garden soil, mixing the two thoroughly. Work the ash a few inches into the plot to make sure it really permeates the dirt.
Dampen the soil with a light sprinkling of water. That will help the corn ash to sink deeper into the dirt before you plant, which makes it easier for the plants to absorb.