35 watts a square foot. 3 bushes could easilly take up 10-12 square feet. if you were frowin more plants, you could fit 8 small ones in that space. basically a small 400 watt hps if you want to keep it at one room, 3 plants.
Match the light to the growspace, 6k lumens per sq/ft. Flo's emit 75 lumens per watt. HPS emit 125 lumens per watt.