Lamp to plant distance
The right distance between lamps and plants can increase yields and potency. It is very important to keep balance and give your plants as much light as possible, but without causing light burn.
The optimum distance between a plant and bulb is when the light fully illuminates the whole growing area with direct light from the source, but it is as close as possible to the plants for maximum lumen intensity.
Indoor lamps used for plant cultivation (HID – High Intensity Discharge) give off large amounts of heat, to such a degree that they could cause damage to the plant if put too close.
The distance depends on several factors that influence on the temperature:
a. Radiation of the bulb
c. Hood design
d. Air circulation, ventilation
You should periodically inspect and clean your light hood and bulbs, especially after foliar feeding. The dust and dirt that collects will definitely decline reflectivity.