None that I know of. A lot of my containers are out in the rain. It's nice because I can generally forget about watering them until the hot part of summer. It's a lot like having plants outside in the ground, really.

I guess if you just put in new soil and the rain is hard, it might throw some out of the pot or wash a little of it away, but after a while that shouldn't happen because the plant will fill in and the soil will become firmer.

Too much rain has the potential to wash out nutrients, leaving your plants deficient. If you're using some type of mix with fertilizer in it, like Miracle Grow, you'd be ok, assuming you're still in the "feeds for up to 3 months" time frame. Otherwise, be careful about letting tha rain "water your plants", as the rain doesn't provide the nutrients that your plants need; that's your job.

Joe

Thanks Joe. My mix does have some fertilizer in it and I added a row of 10-10-10 around the top that doesn't get wet from the rain. Time will tell as this is my first experience with container gardening.

Peat based soils can get waterlogged in the rain. 5:1:1 drains well enough, but nutrients do wash out.