Grow Light Coverage: Matching a Fixture to Your Tent Size
Manufacturers publish two footprints. The bigger one is for veg at lower intensity; the smaller one is what you can actually flower under.
Read the flower footprint
A light advertised as covering 5x5 in veg often only supports flower-grade intensity across 4x4 or even 3x3. Always size to the flower number.
Edge falloff
Intensity drops sharply at the edges of a footprint. Plants in tent corners run 30-50% lower PPFD than center plants and finish with looser buds. Reflective tent walls recover some of that.
Fixing uneven coverage
Rotate pots a quarter turn every few days during veg, keep the canopy flat with training so no plant sits in a shadow, and consider two smaller fixtures instead of one central light in square tents.
Frequently asked questions
- Do reflective walls really help?
- Yes, meaningfully at the edges. Keep tent walls clean and avoid hanging equipment that blocks them.
Keep reading
Legal notice: We do not promote or encourage breaking the law. This site is for adults 21+ growing in states and jurisdictions that have legalized cannabis cultivation, and who are following all legal growing guidelines, plant count limits, and permit requirements that apply to them.