can you compost wool?
Yes — 100% wool composts as a slow-release nitrogen source; cut it small and give it a year or more.
breaks down in 1–5 years; fastest shredded in a hot pile
C:N ≈ 5:1
which bins can take it?
- hot pile yes
- cold pile yes
- worm bin no
- bokashi no
- tumbler caution
- curbside no
- cold pile: It gets there eventually — count in years, not months.
- tumbler: Wool occupies the drum across many batches — sift it out and return it each time.
- curbside: Textile fiber is off the accepted list for nearly every curbside program.
why?
Wool is keratin protein at roughly 15% nitrogen by weight — a C:N near 5:1 — which is why wool pellets are sold as a garden fertilizer rated around 9% nitrogen. The same keratin is cross-linked with disulfide bonds that most microbes can't cut, so only specialized fungi and bacteria work on it — slowly. Lanolin also makes wool shed water, and dry wool barely rots at all.
how to prep it
- Cut or tear into small pieces
- Soak thoroughly — lanolin makes wool repel water
- Mix into the damp center of the pile, not the surface
watch out for
- Superwash (machine-washable) wool is coated with a polymer resin so it won't felt — that coating also makes it a poor composter.
- Wool-synthetic blends leave a plastic lattice behind; only compost wool with a 100% natural fiber content.
often confused with
- Acrylic 'wool-style' yarn — Sold in the same aisle and knits the same, but acrylic is plastic and never breaks down in a pile.
quick answers
Can I use wool as garden mulch instead of composting it?
Yes, and it's arguably the better use — wool mats suppress weeds, hold several times their weight in water, and feed the soil as they rot over a few seasons.
Will wool in the pile attract moths or pests?
Buried, damp wool holds little appeal for clothes moths, which seek dry, undisturbed fiber. Rodents ignore it too since it carries no food scent.