I like Canna in a pot. They can take standing water once sprouted so you can't over water. I grow them in closed pots, no drainage. But they do very well with drainage and watered daily in the summer. Without drainage they don't need a lot of water. You can epoxy drain holes if wanted. The most clay soil you have in your yard is best imo. They do like a fair amount of food. Couple of chunks of fruit tree fertilizer spikes works great and good for months. Many kinds. I like the older kinds, simple green leaf The downside is you really have to divide them every year else they can break a pot. Did mine today. With a little protection from frost, like a roof eve, they bloom through the winter. If frost gets them they will come back from tubers. If you can move the pots to full sun in the winter, so much the better. Disclosure: I've only grown these on the west side of house and in full sun. They bloom pretty much continuously. But each flower only lasts a few days so for best appearance cutting spent flowers a couple of times a week is best.

Just following up on my original post. Thanks to all you here my impatiens are doing quite well under the porch. Here are my lessons learned (and still learning): Osmocote (14-14-14) helped immensely Don't overwater. All 16 pots cannot be on the same watering schedule. Some pots receive full sun, partial sun, no sun. The pots facing east (morning sun) and the west (afternoon sun) are doing the best. The pots that receive next to no direct sun are the least full and are the smallest, but they are flowering. The pots on the west side are getting leggy and will require pinching soon. The west side pots tend to wither a little from the direct last afternoon sun, but they bounce back in the evening. Only water when needed! My only question at the moment is when should I apply more Osmocote? It claims to last 4 months, but is this realistic? Thanks. Dave

Thanks for the replies, everyone. I should have included a bit of back information that would better give orientation about my overall objectives. This first year or two, my main objective is to define the borders of the porch for my two large dogs. Until now, we had a pad and grass up to the pad (pad is the same pre- and post- porch construction) and they could exit the pad anywhere. Now, I want them to get used to exiting the pad onto the sidewalk in the center, because elsewhere will now be beds (and mud and mess and plants to be stomped). That's why I've bombed the front with the cinnamon ferns, to make a sort of visual railing while the dogs re-learn their exit, and while the beds age in with better soil and I get some other plants going (hostas, etc.). For the first year or two. It will be no problem to move the ferns around the corner when that time comes. I've always wanted a mass of ferns on this eastern facing side: My second objective is to create a streamlined mow line. The grass is maintained with a 60 inch deck mower so whatever bed edge I develop needs to allow the mower to move along it easily (I guess rather than undulating what I was trying to get to was smooth curves rather than corners, for mowing purposes). Third objective is LEAST maintenance from a hand weeding perspective. I know it won't be zero, but I'd like to have it controllable without being consuming. Fourth objective is "pretty." I'm not bothered with "curb appeal" in general as the only viewers are anyone coming up the driveway; this is not seen from the street. Eventually, I would like to grow and develop in a pretty foundation border. I got the ferns cheap and they will help my first objective. As I can, I will add more plants and soil amendments, so that is what I'm asking for - where do I EVENTUALLY want to go with this, etc. I appreciate all your inputs! Please add as you have thoughts!

First make sure all your lighting is the same I like LED4000K but you can do 3500K then choose wall color understanding that everything in the space affects wall color so post pics of the spaces after you get the lighting done.