Put together a little greenhouse in my garage to overwinter my citrus plants/trees and some chillies here in Seattle. Have a grow light on a timer above, and a seed mat on the floor to provide a bit of subtle heat (like a lightbulb would) since the garage is not insulated. It’s fully sealed other than when I zip up the roll up door- I was going to install a little fan to move the air but is there anything else I should do to prevent mold/over humidity? There’s a bit of condensation accumulating on the inside and light fuzz on the surface soil/mulch of a few plants which I assume is not ideal. I could turn seed mat off other then when it drops below freezing? First time with a greenhouse and citrus so welcome any tips/advice, please go easy on me 🙂
by GeeDee88
4 Comments
You need a fan to prevent the mold. Your heat mats might be enough for a Seattle winter. Citrus can handle brief periods below freezing.
I’d turn the fan on and if you’re worried about the temperature and you have a light inside, add blankets/tarps to the outside. There are thermometers that can record high/low temps that are inexpensive. You can monitor and see how to adjust your set up.
I’m currently playing around with a similar greenhouse use over in zone 8. If you need more heat, I’ll first recommend covering with a moving blanket especially if you aren’t needing sun.
Add as someone in zone 8, i just accept the humidity.
You have rotting organic material on top of the soil, so that isn’t helping with the mold. Remove the pistachio shells and leaves and stuff.
Greenhouses need airflow, so yeah, you need a fan running 24/7.
That growlight won’t be sufficient the way you have it hanging. It needs to be inside the greenhouse. Between the green house material scattering the light, and the far distance of the light, you might as well be using a porch lamp. Citrus need high intensity lighting. They grow them in Arizona and Florida for a reason. They’re native to the middle east, where the sun is as intense as a laser.
Low light will also encourage mold and fungus to grow.