Ina wrote > ... in big containers if the roots > are fairly shallow, to fill the bottom up > with plastic bottles. Then cover with plastic > mesh before filling with whatever mix is used. I tried this some years ago... many plastic bottles will collapse sooner or later and render your container a mess. This somehow always happens at the wrong time of year for transplanting. Instead, I use a layer of foam packing peanuts covered with shade cloth, which is the most readily-available plastic mesh here. I have tried this without the plastic mesh and the soil sifts its way to the bottom of the container. Cycad enthusiasts often grow seedlings in tall, narrow containers due to their long taproots. (Many cycads have enormous undergound tuberous roots, so they are at least as "bulbous" as some other things we discuss here.) http://www.stuewe.com/products/treepots.php TP414 "Tall One" 4 inch x 14 inch / 10cm x 36cm 0.100 cubic feet / 2.83l We put a small layer of these foam packing peanuts at the bottom to ensure air at the roots, even when the containers are placed side-by-side in tight groups on a concrete surface. If it becomes necessary to separate the foam peanuts from the soil when repotting, put everything into a large container of water. The foam floats. Leo Martin Phoenix Arizona USA