What you see: Green on the exterior of garlic.
What it is: Harmless chlorophyll.
Eat or toss: Eat!
So, why is it safe to eat garlic that’s turning green? Here’s the story.
Garlic may look kind of root-like, but it’s actually not a root — it’s modified leaves. The cloves? Those are storage leaves. The green sprout in the middle? That’s a logically named “sprout leaf.” The papery coating of the entire head? That’s made of dried foliage leaves.
You get the idea. Lots of leaf action here. So, while these bits of garlic anatomy may not look like leaves to us, they still act like them. And that includes having chlorophyll at the ready in case of exposure to light. This clove was probably exposed to too much sunlight, overhead lighting or possibly a big influx of fertilizer. That would have caused it to produce chlorophyll and turn green, says Crystal Stewart, an extension vegetable specialist at Cornell.
(We know that the green in this case isn’t mold because it’s clearly a pigment change within the garlic, there’s nothing fuzzy and there’s no obvious decomposition of the garlic.)
Stewart noted that in the image of the clove above, it’s no surprise that the smooth, pointed area is sporting some green. That’s the portion that used to be closest to the sun. And, of course, chlorophyll is entirely harmless. There’s a chance a greening clove might have a more bitter flavor, but in our experience, it’s unlikely. So, enjoy your roasted garlic or pesto or garlic bread or whatever tasty recipe you have in mind.
Does your garlic have green inside? Perhaps a shoot is growing out the top or you see a sprout once you slice into a clove? Check out our article about little green garlic sprouts here.
*Updated Jan. 17, 2023*