Thanks to both of you. I think the idea of a little umbrella is cute but I like the idea that they should be able to take what nature dishes out. I've been reading the posts here including multiple threads on soil mixes and mine is VERY light and I have a big bag of poultry grit to top off the containers.
I found some HUGE cement planters on Marketplace but they only have a small central hole for drainage so we are planning additional drain holes with a drill bit made for cement. I just hope they don't break! They are lovely cement work with raised birds and flowers and some bits of moss from their previous life.
Since this is my first year and I'm getting a late start with them--I will put them in position AND drape them with plastic umbrellas of some sort as they settle in and then let them fend for themselves against the elements come March. Next winter they are on their own!!!
ONE QUESTION: Do I plant the semps in poultry grit (i.e., is the first couple inches poultry grit?) or do I simply place poultry grit around the plants themselves to avoid water pooling?