if you cover the sides of the building with black/white poly, and then put a layer of mylar on the inside of that, you might do ok; i'd give them as much time as possible, try not to put the covering up higher than you have to (more sidelight the better)


but, if your greenhouse is in plain view, i think covering up the sides would be suspicious in its own right; you know your situation though; i would avoid artificial lighting if you can
whitestalkslongwalks Reviewed by whitestalkslongwalks on . GREEN HOUSE.. DO I NEED LIGHTS?? BASICLY IM THE UK AND IM GONA BE DOING MY FIRST OUTDOOR GROW THIS YEAR, BUT IM USING POLY TUNNELS. BASICLY WE HAVE A HOT SUMMER PREDICTED BUT THE UK IS NOT EXACTLY CALI SO WILL I STILL NEED SOME HPS SUPLEMENT TO GET GOOD BUDS.. THE OTHER THING IS IM GONA BE BLACKING OUT THE GREEN HOUSES WITH CURTAINS FOR CONTROLLED FLOWERING STARTING IN ABOUT JUNE BUT WILL THE SLIGHTLY LESS RED DAYLIGHT AT THIS TIME OF YEAR BE OK..?? ALSO WOULD PEOPLE ADVISE HYDRO OR SOIL FOR THIS TYPE OF GROW??? PLEASE HELP Rating: 5