Led Grow Light Guide 5

Question 1

For the seedling/clone stage, what light intensity (PPFD) is generally recommended?

Accepted Answer

100-300 μmol/m²/s

Answer

Seedlings thrive at a gentle 100-300 PPFD to avoid stress and burning.

Question 2

What is a common PPFD target for the flowering stage of high-light plants?

Accepted Answer

600-1000 μmol/m²/s

Answer

Flowering high-light crops often need 600-1000 PPFD for robust buds.

Question 3

What happens during 'light saturation' in plants?

Accepted Answer

Adding more light no longer increases photosynthesis

Answer

Beyond the saturation point extra light yields no added photosynthesis and may cause stress.

Question 4

Why should you measure PPFD at multiple points under the fixture?

Accepted Answer

Intensity varies across the footprint, strongest at center

Answer

Light is strongest directly below center and weaker at edges, so multiple readings reveal real coverage.

Question 5

What is the effect of UV-A light in small controlled amounts on some plants?

Accepted Answer

Can boost resin/trichome and protective compound production

Answer

Limited UV-A can stimulate protective secondary metabolites like resins and flavonoids.

Led Grow Practice Test