Information for green amaranth. https://en.wikipedia.org/wiki/Amaranthus_viridis

Too bad we can’t see the rest of the plant. I’m guessing this might be a species in the Amaranth genus? Possible the green amaranth (Amaranthus viridis)? Check it out and see if you have a match. Click on images from the included links to enlarge. Best wishes! For future reference. Please include location where the plant is growing, i.e. country, city, province. It would help us narrow down the genus & species for you https://commons.wikimedia.org/wiki/File:Amaranthus_viridis_W3_IMG_3850.jpg