The way this experiment is reported is misleading, I have tried over potting with many bulbs, trees and shrubs. As Roland suggests, other factors come into play. I strongly advise against over potting of most central Asian and European 'bulbs'. If over potting is tried, then optimum growth conditions must be given and care taken that there is a lot of air in the compost. Such lush plants can collapse very easily. Soft fast grown timber might be very handsome and make good pulp but strong timber or a tree grown in character is better grown much more slowly. Of course the roots of plants seek the edges of pots and run around them, just as they would to anchor themselves in a crack in rocks, The water flow carrying air and nutrients which roots in soil seek is found best between surfaces, in this case the surface of the pot and the soil, in the case of my bulbs in pots -between the under potted bulbs and the particles of grit in the compost. Juno Iris HATE over potting, Pogons don't seem to mind. Another factor is that many bulbous plants grow much better as a clump rather than as separate bulbs, a fact to remember when considering the separating of seedlings. I suspect that hormones may have something to do with this. -the sibling bulbs being mutually supportive. Snowdrops are a classic example. I also suggest that it is very sensible of plants to only grow to the size that their roots can support! Peter (UK) On Sun, Jul 1, 2012 at 12:30 AM, Ina <klazina@orcon.net.nz> wrote: > This presumably would also apply to bulbs. And would go with Mike's > comment on these bulbs which just will not do well in pots. > > http://www.bbc.co.uk/nature/18612661/ > > Ina > > -- > Ina Crossley > Auckland New Zealand Zone 10 > > _______________________________________________ > pbs mailing list > pbs@lists.ibiblio.org > http://pacificbulbsociety.org/list.php > http://pacificbulbsociety.org/pbswiki/ >