The movie is about a boy who lives in a post-ecological catastrophe world, where the sun is really intense and anyone spending time outside gets burned. I remember the boy being a (kick?)boxer at the school gym, some parts of the movie are about him getting bullied by the competition, at some point they tie him up in the sun and he barely survives. He dates a girl from school, but I don’t really remember anything else about that.

His father is some sort of insane scientist who is looking for a solution to the sun problem, and progressively turns his house into a swamp/jungle and himself /the father) into a plant monster, who ends up attacking the bullies when they follow the boy home. In the end the boy and the girl are immune to the sun.

I think I watched the movie on TV in the late 90s or the really early 2000s, and it had a B quality feel to it.

I already searched by keywords on most sites that offer movie identification, but found nothing. I expected the title to be “Green” or “Growth” or “Spore” or something in that vein, and there are movies with those titles on IMDB, but none of those is the right one.

Thanks to anyone who can help!

Miki