What are (or where can I find) guidelines regarding how much distance to place between a grow light and the maple tree cuttings (two small "standard" cuttings, one large "air layered" cutting) that I just brought into my garage to protect against frost and the sort of hard winters typically experienced in the Midwest? How long should I have this grow light turned on per day? I determined the distance I placed between the grow light and the cuttings (see pic) by considering a combination of what distance would provide a given daily light integral (in units of [mol/(day*m^2)]) and what distance provided an at least semi-reasonable light intensity as perceived by my own eyes. Right now, I'm running the grow light for 12 hours per day. I'll be looking to return the cuttings to the outdoors in the spring. Thanks!
Seeking guidance using grow light on maple cuttings