Wood ash in the garden
Useful in moderation on acid soils; harmful for acid-loving plants.
Evidence: University extension guidance; test soil firstProfessional review not claimed
What the sources say
Oregon State University Extension says wood ash supplies potassium and other nutrients and raises soil pH, recommends testing pH first, and advises against using it on acid-loving plants.
Evidence assessment: University extension guidance; test soil first. This describes the scope of the guidance we checked, not proof that the remedy works for you.
Cautions
- Do not use on blueberries, rhododendrons, azaleas or ferns.
- Use ash from untreated wood only, applied sparingly.
No method is given for this entry. The guidance we checked discourages this use or shows it does not do what tradition claims.
Ingredients & category
Sources
- OSU Extension: Use fireplace ash sparingly — link and wording checked 30 September 2026
Source-checking is not clinical or veterinary review. Specific historical origin not established from the source reviewed.