Get your leaf symptoms diagnosed with our free plant doctor.
2.) Match light intensity to plant needs
Cannabis plants need more light than most
houseplants. Outdoors, plants thrive in direct sunlight for 8+ hours a day.
Indoors, plants need a grow light. But unlike the sun, you can keep your grow light too close or too far away from your plants.
If you remember that food is light for plants, it makes sense that giving too much (light too close) or not enough (light too far) would cause problems.
Luckily you have a few effective ways to ensure your grow lights are the right
distance away:
Follow the manufacturer's recommended light distance from dance (to start)
Measure light levels with a PAR light meter or PPFD app on your
phone
- Seedlings - 100- 300 µmol/m²/s
- Vegetative - 300–600 µmol/m²/s
- Flowering - 600–1000 µmol/m²/s (700 is average)
Pay attention to plants (most important)
- Move lights further away if you notice symptoms on the on the leaves closest to the light ("light stress")
- Move lights closer if plants are growing "tall" with a lot of space between sets of leaves
Example: Tall seedlings
need more light
