Green, black, or orange spots are signs of contamination. Healthy mycelium is white and fluffy.
Not sure? Do the cotton swab test: gently press a clean cotton swab against the suspicious spot. If colour transfers to the swab, it's likely contamination. If not, it's probably just bruising (which is harmless).
More info on identifying contamination can be found on our website.
If your kit is contaminated, send us a photo along with your order number and batch number.