Hey dudes and dudettes,
I have my grow setup in the basement and the basement temperature is around 66° with 45% humidity. I’m trying to keep the grow tent in a good equilibrium between humidity and temperature and that’s my starting air to work with. I’ve read anywhere from 75 to 80° temp and 75% humidity would be ideal for seedlings and sprouts and a 40-60% humidity for vegetation. My problem is right now I have a fan heater and a humidifier in the tent and I keep getting the readings switching from 69 to 78° and the humidity going up and down. I’m not really sure what else to do to keep the numbers from fluctuating, is that ok? They fluctuate about every hour or so. I have an under the desk oil heater on order to hopefully help not dry out the air but keep the room moist. With all that said My question for the crew is what are acceptable ranges for plants in such young stage I can keep the humidity high and the VPD in a good spot only if the temperatures around 68 69° if I try to raise it with my setup then my humidity goes down significantly and the system starts cycling. I’m starting off with autoflowers so I can get something while I dial in my tent.
Are my pictured ranges acceptable? I have setup my tent different and got the different readings, trying to find the sweet spot and keep the electric reasonable.
Is low 70s ok for plants to grow and yield?
My first grow I don’t expect to hit it out of the ballpark but it would be damn sure nice and motivating 🙂
Thanks crew
Instead of the fan heater, I would try and use a heat mat. It would be more efficient and I believe that it would get better heat transfer into the pot/media than hot air around the leaves. Those swings will be almost proportional to the volume of air that is in your grow, eg. the larger the air volume the more minor the swings. I don’t know how you’re fan is set, but I set mine to a very low setting to circulate fresh CO2 constantly and to only evac more air when the temps/RH get too high. This could help mitigate those swings if your fan is turning on and off to cycle in the CO2. Until you get some wet soil/media I don’t think your grow will actually get settled into its veg/flower state, at least mine won’t (18″x36″x62″ tent). Also, the humidity will directly affect the temperature in your room, and vice versa. So you will always see lower temps when the humidifier comes on. Think about it like this, the water in the air is evaporating thus lowering the temperate in the air. So anytime water is evaporating the surrounding air will be cooler from this phase change. This is just my own logic, as I can’t find much info online about this. All looks manageable though, so Happy Growing!
I have an ac infinity 6 inch for my 2×4 tent. I’m trying to dial it in. I keep it at a flow of 1 always and bump it up to 5 as my high. Trying to control the swings but I guess my question is, are these swings ok and will that rang work for my plants.
I just bought inkbird humidity and thermostat controls to monitor and adjust my humidifier and heater. I still think the problem is the dry heat .
Since it is the basement I could use a heating mat undery fabric pots but would that affect the plants ability to breathe in the cool air still, the basement is mid 60s…
Thanks for the input and feedback I really appreciate it.
I don’t think the mat would negatively affect the roots pruning in any way, especially since you wouldn’t be using it throughout the whole grow only in early veg. I think those swings won’t be an issue at all, and they should go away with the introduction of bio mass and regular waterings. Those will add to the base level of humidity so your humidity should level out in veg., thus throughout veg/flower the humidity should raise naturally. As you already know this will lower VPD, giving you the opportunity for higher light intensity later in veg/flower. I also want to add that if your having trouble with a large environment simply make it smaller. I use a clear glass to cover my seedlings to raise the humidity in a mini climate, then I only manage my temps in the tent/seed mat. This works to give them some strength to combat any negative conditions. I believe that in very early stages the root temperature are more important than in all other stages, thus proper root warmth has always given me great results. Also I have basically the same settings on my AC fan, my triggers are 82F and only in flower do I set 65%RH.
Hope this helps.