I've always thought green fingers, but now you have set me doubting

My son thinks fingers are the English and thumbs are American ?

Agree, I've seen both. In that context I would include thumbs as being one of the fingers....

Have just asked daughter in California ( landscape. gardener ) if they have a version.
Meanwhile - thanks for replies.

Green fingered here and Green thumb is a lawn care company in the UK.

The term Green Thumb can from an article in the Ironwood Daily Globe newspaper (USA) in 1937. The term Green Fingers originated in 1906 in the novel- The Misses- Make Believe written and published in the UK. Both seem to relate to the staining of these digits from the Green algae growing on the surfaces of clay pots. That was a really good question Hank.

They are very good - we used to hire them when we had a very big lawn and no time.(And no they aren't paying me!)

Thanks for that L my daughter agreed with you. I must send a copy of your reply to her.

Along with my regards please:)

I've always been all thumbs...er, I mean green thumbs. :)