Cast Iron Plant, Zone 5 8 UC Berkeley Plant and Microbiology josiahmackey Growing wasabi has been one of our toughest challenges. To date, we've yet to pull off a successful harvest. A big part of that struggle is trying to cultivate this cool, shade loving Heres the secret: timing is everythingand so is the right fertilizer. Want to know exactly what I use and when to use it?, Comment fertilizer below and Ill send you the link to my blog post