I've used shiny aluminum foil insulation laid on the ground on the south side of my sunroom to add heat and light. Also have a reflective material, Extenday, on the floor of my greenhouse. You also might consider a better covering on the greenhouse. Mine, double poly, probably blocks at least 50% of incoming light. Just remember more light in means more heat. So you need a good cooling system. If you are talking reflective plywood on the east and west side it can't be very tall or it will block light early and late in the day. And if your covering material is the real issue, trying to push more in won't help much.

Plantings. Trees. Shade. Surrounding the home with abundant green- as I live in an irrigated desert. Let the beating sun roll onto canopies of trees surrounding me. Misters. Keeping misters running keeps the back porch twenty degrees cooler than the reported temperature! Arrange the garden & patio with an overstory & understory - with fruit trees in season, and evergreens surround furthering both privacy- and all important to me- a beautiful scene close by during hazardous air quality. Then when the sunlight- which you so kindly mentioned to me- bakes the smog & the air quality is unhealthy to all "hazardous" instead of looking at puffy white air hanging like fog on a 110 degree day- and seeing a gray brown yellow overcast 'cloud'- on a "clear" cloud free day!!! One can simply see the inside of a tree branches cascading merrily. Go out and pick a fig. a nectarine. a peach. make life a peach. But when you leave the house and drive about- ouch! the limited eye sight and polution haze can really hit you by surprize!! Until I learned about sunlight & heat increase of pollution limiting visibility I wondered about early cataracts for me.

Thank you for your help everybody, I finally found one color that works in both rooms. It is a BM Gentle Cream which is in the off-white collection. I wanted more color but it looks like with the northern exposure combined with the low ceiling and narrow rooms there is just no visual space for anything more intense. Gentle Cream actually lives up to its name, it doesn't look pink or peach in either room and not too yellow either (Papaya was a little too yellow). And yes, the type if bulbs makes a big difference. We have some kind of "true light" in the DR, similar to Reveal and this particular color looks more yellow there. The LR has halogen recessed lights and the color has a slight green tint to it in that room. I also encountered this issue in my kids' bathroom. Picked a countertop which looked beige-cream in the showroom, almost exactly like the color of the tile we selected. I did cheked the sample at home but during the day, the lighting wasn't istalled yet in the bathroom. Once installed, the counter looked almost yellow in the bathroom with the regular flood bulbs. I couldn't believe I was so off with the color! However, after we switched the bulbs to white light it looks a lot closer to what I thought I picked

hi I can't tell from the pic but it looks like Adiantum capilus veneris, venus maidenhair?? There are over 200 types . they range all over the world from temperate to tropics so obviously would have much different conditions. I grow them in pots in my deep shade garden area . IME they will tolerate very deep shade but no direct sun. they seem to like a LOT of water but will rot if too much croak if too little . The usual wisdom for them is bright indirect light ,moisture retaining ,organic soil but well draining temps above 60 even for the temperates . While I follow all that mine always tend to look a bit sparse . When I was in Costa Rica I saw them growing by the gazillions in "seep" areas as well as rock faces constantly sprayed from waterfalls. have no idea which kind but they were gorgeous!!lol I've moved mine to a dedicated fern bed underneath some tree ferns where I'm using only rainwater. I'm suspicious of my very hard alkaline tap water. too soon to tell if effective but the tree ferns are responding as well as some other types, Time will tell i guess Good luck gary