Sometimes putting the pots under the eaves of a house or garage is enough to reduce the impact of heavy weather. They still need lots of sun though; if they don't get enough they will get "leggy," meaning they get deformed, growing long and spindly.

I know an old gardener who had a home-made cart made of plywood, about 3'x8' with a small lip all around and large casters mounted underneath. In spring, he would put all his small plants on it and pull it in or out of his garage to protect from frost damage.

I have seen pictures of coastal plant pots (probably at a hotel or restaurant) with cute little translucent umbrellas over them. This has been the subject of ridicule in serious gardening circles, but I guess if the rain is so heavy that it knocks off the blooms, then they are protecting their investment.

If we had to protect our young plants, we would probably use garden cloches. They are a sort of a mini-greenhouse made of glass or plastic with a hole in the top for ventilation. Any garden shop will have them. Improvised versions include gallon jugs from milk/pop/water, provided that aesthetics don't matter. For larger plants, I use my all-purpose garden scoops -- discarded 5 gallon water cooler jugs with the tops cut off (use a handsaw or they will crack). If you cut off the bottoms instead, you have an instant mondo cloche. If you cut off top and bottom, you have a mini greenhouse sleeve that works great, though not for rain protection. (BTW, around here the older jugs are #7 and not recyclable, so I'm saving them from the landfill.)

Hope this helps.