UVA does penetrate glass.@Markw84 . Need your help regarding UVA please.
I was under the impression that there is a certain amount of the UVA spectrum carried with all light bulbs.
UVA is at 400nm bordering where the visual light spectrum starts.
When I got my LED lights for my tort house I got the red and blue spectrum. I can't find the exact LEDs I got but I'm sure they were blue at 415 nm and red at 660 nm. Because it looked like a disco from the 70's I later added some white LED's to mask the visual red and blue look. The aim of all this was to get plants to grow. Plants need UVA, correct?
Does UVA pass through glass, as it sits at the low end of the visual spectrum.
If not how do we manage to grow plants indoors without UVA. For example I've grown chillies/tomatoes in my house on the windowsill. Then there's green houses, Polly tunnel etc, how does UVA get in there if it's not with light to make plants grow healthy?
Help