Led Grow LED Grow Light Spectrum & Light Science

Question 1

Which wavelength range is primarily responsible for vegetative growth in plants under LED grow lights?

Accepted Answer

400-500 nm (blue)

Answer

500-600 nm (green)

Answer

600-700 nm (red)

Answer

700-800 nm (far-red)

Question 2

What is the term for the ratio of red to far-red light that influences plant flowering?

Accepted Answer

R:FR ratio

Answer

PAR ratio

Answer

PPFD index

Answer

Lux coefficient

Question 3

What does PAR stand for in the context of LED grow lighting?

Accepted Answer

Photosynthetically Active Radiation

Answer

Plant Absorption Rate

Answer

Peak Active Response

Answer

Photon Absorption Range

Question 4

Which color of light is most associated with promoting flowering and fruiting in cannabis under LED grow lights?

Accepted Answer

Red (660 nm)

Answer

Blue (450 nm)

Answer

Green (530 nm)

Answer

UV (380 nm)

Question 5

What unit is used to measure the intensity of PAR light delivered to a plant canopy?

Accepted Answer

PPFD

Answer

Lux

Answer

Lumens

Answer

Kelvin

Question 6

What is the approximate PPFD range recommended for cannabis plants in the vegetative stage?

Accepted Answer

400-600 µmol/m²/s

Answer

100-200 µmol/m²/s

Answer

200-400 µmol/m²/s

Answer

800-1200 µmol/m²/s