Hi, I've been reading all the posts on what to put in your pots with interest. When I first started expanding the number of bulbs I grew I was eager to follow the "rules" I read from the experts about what to use in a mix but I have long since decided there is not a correct way to do any of this. A lot of ways and materials work and it depends on what you have available, how able you are to lift heavy pots, what your conditions are like (temperatures, amount of rainfall, sunshine, etc.), and how much time you have to water and generally provide special treatment for your plants. Over the years I've tried a lot of things that have been suggested by others and have dismissed a number of them since things just didn't do well for me grown that way. I am reminded of a post by Bob Werra who described his growing medium and asked and answered his rhetorical question about why that mix, with just because. Reading the most recent posts about adding light weight items to large containers to reduce the weight makes me wonder why not just use smaller pots. Some bulbs seem so much happier in larger pots because they have increased root run or want to be deeper in a pot. If you add barriers like bottles, cans or contained styrofoam it would seem to me that you would be decreasing the amount of room available for the roots. It's why some people recommend not to add crockery to the bottom of your pots, saying it doesn't help drainage, it reduces space for the roots. If the plant doesn't need the extra space, why not just plant accordingly? Judy's comment has given me courage to say what I was thinking. Mary Sue in Northern California where we have continued to have DRY warm weather and where each day something new is in bloom.