Bubble wrap is polyethylene, which is a poor IR absorber. You need something that will absorb IR, like PVC, for your clear parts. Your north wall should be insulated with reflective insulation to trap IR. Optionally, your east and west walls should be as well. Any north-facing roof area should be as well. Soil: It depends. Soil in small amounts is a very poor insulator, but if the heat has to travel long distances, it's a great insulator. If you want the soil to be a heat sink, bury some insulation outside the greenhouse. I'd recommend starting at the greenhouse walls, going a few inches down into the soil, then spreading out laterally for at least a foot, instead of going straight down. It's easier, and it walls off a larger area of soil, than going straight down. Without that, the mulch is actually being your friend, as your soil heat near the walls would leak outside. If you want to clear part of the area of mulch, clear the center of the greenhouse and leave the much along the edges.

Baby Palm left open, no protection

Thank you. I got 50 Areca catechu dwarf seeds from Thailand a few years ago. Out of the 20 or so that germinated only one turned out to be a true dwarf. I have since found out that this is quite common. The other seedlings have grown into what appear to be regular size A. catechu. One is four feet tall. If you are really interested, I have another true A. catechu dwarf that I got from another source, but they are kinda pricey. Here's some more palms in the greenhouse Pholidostachys pulchra Pinanga ceasia Some Heliconia plants, too Bihai Lemaii Variegata Helicon zebrina

See this is why I need you guys....I have no idea what I'm doing with sago palms. This is my first year even owning a sago palm and now I have right at 100 pups that are putting out fronds. My plan was to keep them in my garage greenhouse with temps around 70-85 degrees with lights. I have a really huge garage built on to my house that we don't even use so I turned half of it into a greenhouse and grow my plumeria's in it over the winter. I have a heater that keeps the temp exactly where I want it. I have lights (white lights during the day and blue/red LED lights at night). I'm having a big plant sale next year so I thought if I could keep the sago palms growing all winter they would be bigger for the plant sale. I have no problem putting the sago palms in the garage and letting them go dormate if thats what I need to do (it would actually be less maintenance that way). I really don't want to take them out of the soil though. So what do you guys recommend? Should I even try the greenhouse or let them go dormate over the winter? I use Bayer spray for bugs and that normally does a really good job on my plumeria's but I've never tried it on sago palms before.