I would guess they are responding to a perceived existential threat. Many perennials bloom and fruit after root pruning or disease infection because that is the only way to pass on their (selfish) genes. A similar strategy makes annuals repeat bloom when they are 'deadheaded'. My best guess, Tim On Sat, Aug 22, 2020 at 4:55 PM Lee Poulsen via pbs < pbs@lists.pacificbulbsociety.net> wrote: > So two things: > > 1. a. After many years of growing Vagaria parviflora, all of a sudden my > two pots have sent up scapes for the first time. > > 1. b. I didn’t know they bloomed oporanthously (to use Jim McKenney’s apt > term), in the dead of later summer while I thought it was completely > dormant. I guess it’s like Amaryllis belladonna, a few of which have also > started blooming. > > 2. Why does it seem that some bulbs refuse to bloom until they’re > repotted? What does repotting simulate in nature? > > > I got one bulb of V. parviflora from M&C Willetts in 2004. (I don’t think > they’re around any more.) It leafed out every autumn and grew fine every > winter here in So. Calif. But I never got any flower scapes. Last Fall the > pot it was in split. So I repotted it. By then there were a number of > pretty large healthy bulbs about 2 in/5 cm in diameter such that I had to > repot them into two 2-gallon pots instead of the common/typical 1-gal. pots > that are everywhere. (I don’t know the metric equivalent pot size.) Now all > of a sudden they bloom for the first time in all those years, and several > of them are sending up scapes in both pots. > > This is not my first experience to have bulbs go crazy blooming after > repotting, and I don’t think it’s merely because they were too crowded. > I’ve had bulbs not bloom even when there were only one or two or three in > the pot, they then get crowded, I repot with one or two or three bulbs in > the new pots, and the next season they go crazy blooming. Another example > for me is Tecophilaea cyanocrocus. In their case, it’s not that they don’t > bloom. They always bloom. But the growing season after repotting (and I > still fill the pots with bulbs when repotting), the entire pot gets > smothered in flowers to where you can’t see the leaves or the soil or > anything else. The royal blue variety is breathtaking when this happens. > > So what gives? > —Lee > > > _______________________________________________ > pbs mailing list > pbs@lists.pacificbulbsociety.net > http://lists.pacificbulbsociety.net/cgi-bin/… > _______________________________________________ pbs mailing list pbs@lists.pacificbulbsociety.net http://lists.pacificbulbsociety.net/cgi-bin/…