Not true. You do NOT need UVB for plant growth. What matters is that the light source is the proper color temperature (kelvins), and the lumens of said light source. Bulbs with a kelvin rating of 6500K are fine for most foliage plants and are considered "daylight" spectrum. The lumens required vary, depending on the depth of the enclosure and the species of plants you are keeping.But you will need some source of UVB to stimulate plant growth.