There are some verigated threads that will work for you. Poly. cotton , rayon they make all kinds now! I would test before putting on something important! Live Laugh Download Stitch!
I just know multicolor-thread but tere are also combinations in green shades you can use.
Maybe you have better chances when you post this question in the PUBLIC-tab. Here in PERSONAL is more the corner for everything outside embroidery and crafting (family, jokes etc. ;o)
Greetings, Bettina