Wood ash can help improve acidic soil and can be used on plants that are more tolerant of alkaline, such as junipers and asparagus. Do not apply wood ash to acid-loving plants or to alkaline soil. Limit ash use to less than 20 pounds per 100 square feet annually.
About this Author
Jill Harness has written on a variety of subjects for more than 10 years. Her work has appeared in various print and online publications, including "San Diego City Beat," "Mental Floss," Rue The Day! and Neatorama. Harness has a Bachelor of Arts in journalism from San Francisco State University.