Enchant artifact or creature
As long as enchanted permanent is a creature, it gets +1/+3 and has reach and "{T}: Add {G}{G}."
Channel — {1}{G}, Discard Careful Cultivation: Create a 1/1 green Human Monk creature token with "{T}: Add {G}."
Discarding the card is part of the cost to activate a channel ability.
If a channel ability requires a target, you may not activate it without a target just to discard the card.