One of the most important factors in achieving maximum yield in a grow room is temperature control. This is crucial. Not only do we need to control it, we need to monitor it. So how do we do this? An indispensable tool in your garden to measure temperature is what we call a min-max. Very inexpensive item, all it does is measure minimum and maximum temps and humidity. It's very common to be able to get this item with a probe, which we can actually place right at plant canopy. Now this is important. A lot of temperature control devices. For example, a cruise temp, you can actually see this is designed to encourage you to mount it on the wall. So if I mount this on the wall, I am now controlling my garden, heating or cooling, based on the temperature of the wall. I'm not growing wall. I'm growing flowers. So what's the temperature that matters? It's the temperature at the plant canopy. This is the temperature that we have to pay attention to and control our garden based upon. So if we have our probe at plant canopy, we can come into our garden on a regular basis, ideally every day, we can check our min-max. Okay, our maximum temp was, our minimum temp was, we can clear that. We can also check it at the unit itself. And that way we know the minimum and maximum temperatures were okay while we weren't there. We know that none of our equipment was failing. Not only do we have to control lights on temperature, which should be 80 to 85 degrees Fahrenheit, typically, we have to control lights off temperature. So lights on temperature is controlled with cooling equipment. So we're either using exhaust fans, air conditioners, chillers, some method of cooling. That method of cooling has to be controlled by cooling thermostats, okay? So if we choose to utilize a cooling thermostat like the cruise temp, pretty good thermostat. So it's got a temperature sensitive coil filled with hydraulic fluid, pretty accurate. But if you place it on the wall, you are not going to have complete control, accurate control of your garden. So really, you would have to have some kind of way to hang this in among your plant canopy, maybe a post that it sits on and then hook it up to your cooling equipment. Other options for cooling control during the light-sawing period might be something like this, a ranko, with a digital thermostat with a probe. So this gives us a little more flexibility as to where the actual thermostat can be mounted because we can get the probe over to where our plant canopy is. This is ideally what I recommend. If you come in my garden, you're going to find digital thermostats all over the place with probes all hanging right in among the plant canopy, controlling a variety of cooling equipment, backups in case one cooling equipment system fails, there's another one to take its place. And that way, I'll never walk into my garden and find out it hit 98 degrees and now my plants are damaged. So these are indispensable controls to be utilized in your garden. Lifting lights off temp is also important, especially in cooler climates. Around October, I have so many people come into my store and say to me, why aren't my plants growing? Why aren't they drinking? I say to them, well, what's your lights off temp? They're like, I don't know. They don't even have a min-max in their garden. They're not checking their minimum temps. There's no heaters in there. Before you know it, you find out it's 60 degrees. The plants aren't growing. They're not drinking. Major problem. So we need to have a heater in there on heating thermostats to control that lights off temp so it never goes below 70. These are crucial parameters. You want to be 80 to 85 lights on, 70 to 75 lights off, 10 to 15 degree differential between lights on and lights off. And again, it's not the temperature on the wall. It's the temperature at the plant canopy. High temps can cause all kinds of yield losses. They can cause your flowers to be light and fluffy and airy, not dense at all. They can cause retarded growth, bench spikes. High temps have to be controlled. Low temps have to be controlled. Again, plants love consistency. Use these controls to give your plants a consistent environment. And they again will reward you with that maximum yield.