I have just bought a house and the flower bed which is about 15' x 4' is over grown with weeds and dead flowers. How should I go about clearing it? Should I spray it with weed killer and then pull up all the weeds and flowers? Or should I just pull them up, I don't want the weeds to come back. We have plans to plant a small tree and flowers but I want to make sure I treat the soil before I plant again. Any tips? Thanks!