Jim, I have heard air pressure (specifically the swings to low pressure that come with the return of rainstorms) could be the signal. I tend to repot no later than Oct 1 because the bulbs start to wake after that. I have found that the new roots will only grow very, very slowly until soil moisture arrives and I have found new root buds as early as July. -|<ipp ________________________________ From: pbs <pbs-bounces@lists.pacificbulbsociety.net> on behalf of Jim Barton via pbs <pbs@lists.pacificbulbsociety.net> Sent: Tuesday, October 13, 2020 7:42 AM To: pbs@lists.pacificbulbsociety.net <pbs@lists.pacificbulbsociety.net> Cc: Jim Barton <jimb@customwindowsupply.com> Subject: [pbs] Calochortus roots Last Saturday I dug up a pot of Calochortus vestae to repot them for this coming growing season. I was surprised to see that the largest bulbs were beginning to put out roots. They had been outside all summer with no water since the rains stooped last March. I have wandered how do they know it's time to break dormancy. Do they have an internal clock, is it temperature changes, daylight length (how that would work I don't know as they have 3 inches of soil over them?). Sunset zone 14. Jim Barton _______________________________________________ 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/…