Garak, Your observations and interpretation are very likely correct. My experience is only with the nursery production of Zantedeschia and garden cultivation in Mediterranean climates. Hormone treatment is perhaps most useful in the cut flower industry and potted bulbs where optimal flower production is desired. Mark Robertson USDA hardiness zone 8a, Sunset climate zone 4 > On Sep 7, 2019, at 8:26 PM, Garak <garak@code-garak.de> wrote: > > Hi Diane, > > it COULD be just the storage alone - I dig up my Zantedeschias every winter and store them dry in the basement - round about 9°C - and I've never had any trouble getting them to flower as long as they get adequate light in summer. I guess leaving them in the ground in BC in winter deprives them of the drought stress they get in winters in South-African summer rain climate. Maybe the GA3 s(t)imulates a natural process happening when the plant gets dry? > > Am 08.09.2019 um 00:37 schrieb Diane: >> Thank you for the explanation, Mark. >> >> So, the bulbs would need to be dug up every year in order to be treated. I wonder if the parental species are some that require fires before they bloom in the wild. >> >> Diane >> >> _______________________________________________ >> pbs mailing list >> pbs@lists.pacificbulbsociety.net >> http://lists.pacificbulbsociety.net/cgi-bin/… > > > -- > Martin > ---------------------------------------------- > Southern Germany > Likely zone 7a > > _______________________________________________ > 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/…