[Hot Weather Alert!!] Easy Ways to Beat the Heat
It's that time of year again. Temperatures spike and grow rooms overheat. If your grow room's getting too hot, here's what you can do.
1. Grow Lights
Your lights kick out the most heat in your grow room. Unless you want to cook your plants, follow these tips:
Run Lights At Night
This is the coolest time of day! Since fans don't have to work as hard, running costs should drop.
Lights are a big source of heat - raise them up and away from your canopy if your grow room gets too hot.
Keep Ballasts Outside
Keep them (and the heat they produce) outside your grow room.
Swap to cooler lights
If you don't want to swap out your HIDs, use an air-cooled light (like the DARKSTAR).
Use a dimmable ballast
Dimmable ballasts are digital. Digital ballasts already emit less heat than magnetic ones running at full power. To reduce heat output further, they'll dim lights right down to 250W.
Remove a Light
If worse comes to worst, remove a light! Don't forget, you'll need a LightRail to increase coverage from remaining lights.
The obvious thing to do is to extract more air. You can also:
Use A Speed Controller
With a speed controlller, fans will automatically speed up when your grow room needs cooling.
Be aware of intake air
If the air outside your grow room is hotter than the air in it, first make sure you're drawing air in from the coolest place inside your property. If nowhere is cool enough, you might need to switch intake fans off. Otherwise you'll just be heating your grow room further.
Replace Carbon Filters
This streamlines your airflow. Make sure you use metal bends rather than depending on twisted ducting.
Target hot appliances
A small Black Orchid fan will suck hot air away. Even if the appliance is outside your tent, you still want to cool it, otherwise you'll be warming intake air. If the appliance is in your tent, duct any hot air through a carbon filter. If it's outside your tent, duct straight out of your window.
3. Circulator Fans
To help stop hot microclimates forming, use air circulator fans.
Point them at anything that gets hot - like chillers, lights, ballasts. Even if the appliance is outside your tent, it'll still be warming intake air - make sure you cool it. If circulator fans aren't cooling it enough, use an inline fan to duct air through a carbon filter or out of a window.
Aim them at corners
Some of our low profile options will help you get at nooks, crannies and corners. Otherwise they'll become very hot and humid - a breeding ground for mould.
Avoid your canopy
If you point them directly at the tops of leaves you can cause windburn. The DiffuseAir is great for preventing this.
4. CO2 Levels
Remember how photosynthesis works?
Light + CO2 + Water = Energy
If plants have the light and water but not the CO2, they can become stressed.
Add CO2 to ensure photosynthesis can continue at a really high rate. This'll increase growth and help plants cope with high heats of up to 29oC - 30oC.
The best bit is that high temperatures actually improve CO2 absorption - it's a win all round.
MyCO2 Bags are a great option. They're activated by you so won't release any CO2 until they're in your grow room.
5. Humidity Control
As your temperature goes up, so should your humidity. A higher humidity helps:
- Prevent over transpiration (where plants lose too much water through leaves)
- Bring your temperature down (2 - 3oC avg)
- Keeps the stomata on leaves open (great for photosynthesis, which relieves heat stress)
Slow rate of pests breeding
If using an RAM Humidifier, you can fill it with ice cubes of freezing cold water to help reduce temperatures. If using a Professional Humidifier, fill it with ice packs or big ice chunks. You'll need to top up your humidifiers 1 or 2 times a day.
6. Nutrient Solutions
In summer, you need to really keep a close eye on your feed - especially if you have a hydro system where roots are naked and exposed.
Use a Chiller
The easiest way to keep your nutrient cool (18oC - 21oC) is with a nutrient chiller. It acts as a mini refrigerator.
Check It More Often
In summer, as plants use more water, your feed becomes too concentrated, which can cause overfertilisation.
Keep a close eye on your pH & CF. If your feed becomes too concentrated, add some water.
Use VitaLink Chill
Use Silver Bullet Roots
If your nutrient temperature becomes too warm, root diseases can take hold. To kill 99.99% of root diseases, add Silver Bullet Roots to your tank. A small dose with every tank change is all you need.
Grab some Iceline
Another quick win is Iceline Pipe, which can reduce your nurient temperature by 3oC - 8oC.
The main problems you get in propagators during summer are caused by your temperature or humidity.
Temperatures over 27oC will start to cause issues.
To keep your propagator cool, don't overdo it with your lights. Raise your light height if you need to. You can use ice packs to cool your nutrient solution in an Aeroponic Propagator.
If using a heated propagator, think of putting it on a timer.
Too much moisture is a big cause of failed rooting. Aim for a humidity of 70% - 85% RH and make sure:
- Rooting cubes aren't too wet
- No water or solution is in the propagator tray
- Only a light mist of moisture is visible on the propagator lid (no droplets!)
Don't forget to make sure there's always enough nutrient solution or water in your propagator.
During summer, pests breed quickly! And they love the dry and hot conditions in your grow room - especially spider mites.
You don't need to do anything drastic. A lot of it is just common sense - like preventing cross-contamination and checking plants.
Be on the lookout
Take Preventative Action
Leave your light running with your extraction off for a couple of days after finishing a crop. This'll send pests scurrying out your grow room!
9. Tent Size
If you're really struggling, try a taller tent.
The standard tent size is 200cm tall, but you can easily get a 215cm in your home. That extra 15cm of headroom will really make a difference.