Led Grow Light Guide 2

Question 1

What unit measures the amount of photosynthetically active light reaching a plant's canopy per second per square meter?

Accepted Answer

PPFD (μmol/m²/s)

Answer

PPFD measures photosynthetic photon flux density at the canopy in micromoles per square meter per second.

Question 2

Which light spectrum range primarily drives vegetative leaf growth in plants?

Accepted Answer

Blue (400-500 nm)

Answer

Blue light promotes compact vegetative growth and strong stems.

Question 3

What does the term 'DLI' stand for in indoor growing?

Accepted Answer

Daily Light Integral

Answer

DLI is the total amount of PAR light delivered to a plant over a 24-hour day.

Question 4

Which spectrum is most associated with promoting flowering and fruiting?

Accepted Answer

Red (600-700 nm)

Answer

Red light strongly stimulates flowering and fruit development.

Question 5

What is a key advantage of LED grow lights over HPS lights?

Accepted Answer

Lower heat output and higher energy efficiency

Answer

LEDs run cooler and convert more electricity into usable light than HPS fixtures.

Led Grow Practice Test