Marigolds are a genus of annual or perennial, mostly herbaceous plants in the sunflower family (Asteraceae or Compositae).
It was described as a genus by Linnaeus in 1753.
The genus is native to North and South America, but some species have become naturalized around the world.
One species, T. minuta, is considered a noxious invasive plant in some areas
So can guinea pigs eat marigolds?
As an occasional food, they are fine for them to eat. But as they hold no nutritional value for them, they shouldn’t be a regular part of their diet.
However, the odd one or two should be fine for them.
Make sure they haven’t been sprayed with pesticides or insecticides though, as these a poisonous for a guinea pig.