Marijuana grow room heat is hard on your plants and on your bank balance.
Many of us growing right now in July are experiencing warmer than average temperatures that keep our air conditioning cranking.
When grow rooms get too hot, buds become thin, plants grow too tall and weak, they suck down lots of water, which increases the danger of overfeeding, and electricity bills skyrocket.
We gave you another article about summer marijuana grow room strategies, and here are some more tips:
- Start bloom phase early.
If our grow room temperatures were normal instead of over-hot, we’d let our grow phase plants get as tall and bushy as we want before we switch to bloom phase lighting.
But summer grow room heat might force other choices such as starting bloom phase early.
As long as your plants have enough root development and aboveground branching and height, starting early means less lighting hours and lower heat.
But there’s another tactic: because hot grow room temperatures during bloom phase create thin buds, you could delay bloom phase.
Keep your plants in grow phase until over-hot conditions recede naturally or until you add air conditioning and/or exhaust capacity.
One thing to know: if you do choose to let your plants stay in grow phase longer than usual, you’ll have to cut the tops off your grow phase plants, do extra shaping and trimming, and expand their root zone container size.
- Use dry ice. It adds carbon dioxide (CO2) and it cools your room.
Put the dry ice blocks in shallow trays near your buckets, pots, or other root zone containers.
Use a circulating fan at ground level to blow on the dry ice and circulate CO2 up into the canopy.
Don’t touch dry ice with your bare hands.
Keep blocks of dry ice from touching plants, pets and people.
- Have your lights on during the coolest hours of the day and night.
My summer marijuana grow room lights come on at 10 p.m.
- When rain or heavy cloud cover is present, your dwelling isn’t taking on as much heat.
That’s a good time to run your lights, even if it’s out of your regular cycle, if you’re in grow phase.
- Install an attic fan controlled by a thermostat.
- Install ridge vents on your roof.
- Lightly mist your plants with 5.7 reverse osmosis water cooled to 69°F.
Be careful not to create large water droplets on leaves, because they act as magnifiers for light and this can burn your leaves.
- If you have a pest-free enclosed space such as a patio or greenhouse, cycle your plants out there from time to time — as long as that space has lower temperatures than your indoor grow room.
- Load up on nutrients and supplements that help plants deal with heat.
This doesn’t mean for you to feed extra parts per million.
In fact, your plants will be using more water in super-hot grow room conditions.
If you run your regular parts-per-million feed program while plants are consuming more water than usual, you burn your plants with excess nutrients.
The key is to reduce overall parts per million while stacking supplements and nutrients that help plants deal with heat.
These include vitamin B (B-52), carbohydrates (Bud Candy), potassium silicate (Rhino Skin), and humic and fulvic acid (Ancient Earth).
If your plants are consuming much more water than usual, do a periodic short flush to keep their root zones clear.
Excessive heat is the enemy of cannabis plants and fat buds.
If you have to grow cannabis in summer, and your grow room temperatures aren’t controllable the way they should be, the strategies we’ve given you in these two articles will help you achieve your best outcomes.