so a while ago one of my homies said that he used a piece of white cardboard a s a light refelctor for a plant he had outside....does anyone have any expiernece with this??????

White does reflect well - not sure the value of using a reflector outdoors though...

Just opinion, but unless the plant is in too much shade (and even then...) I don't think I'd bother with trying to use a reflector outdoors.

Good advice given above, plus this could act as a beacon to any fly-overs!! Outdoors the Sun doesn't need any help, lol.