Good point Jane. I had meant to include my location, which is Carnation, WA, quite a bit east of Seattle and against the foothills of the Cascade mountains, where we receive about 50 inches/year—30% more than Seattle (forecast calls for 4 inches of rain over the next three days, for instance, and thats not particularly unusual this time of year)—and the humidity is quite high even during the warm summer months. I have lost plants to moisture-related decay (for example, a pot of alstroemeria seedlings) even against that south wall after having received no direct moisture for months. An empty 1-gallon pot of soil left out in the open on my property would almost never completely dry out. On the other hand, the only bulbs I put against that wall are from climates that are significantly hotter and drier than mine (e.g. lowland/inland South Africa and California). Also, relating to your point about bulbs growing deep in the soil where temps are moderated, I do pack the pots tightly together in deep trays so that they are buffered somewhat from the baking effect of the direct sunlight. On Thu, Dec 19, 2019 at 12:21 PM Jane McGary <janemcgary@earthlink.net> wrote: > When we discuss how we grow certain bulbs, I think it's necessary to > mention where we live. Cody, who posted recently, lives in a suburb of > Seattle, Washington, where it may be safe to keep dormant bulbs "against > a sunny south-facing wall," unwatered and with at least 15 days of high > temperatures in summer. I live a couple of hundred miles south of him, > near Portland, Oregon, and I'd kill a lot of bulbs if I did that in > summer. Portland is in an inland valley, east of the Coast Ranges and > west of the Cascade Range, and has more sun and lower humidity than > Seattle in summer. If you live in California, don't do that at all, > please. British gardening books often recommend "summer baking" for > potted geophytes, but we have to consider the climate differences where > the author is living (some parts of the British Isles get much more sun > than others, and/or greater summer humidity). I mention humidity, rather > than just rainfall, because it can affect soil moisture in pots. > Remember, too, that many (though not all) dryland geophytes keep their > bulbs deep in the soil, where temperature and to some extent moisture > are moderated. > > I manage soil moisture for dormant bulbs by keeping them plunged in sand > and covered against rain. Half my collection is sprinkled lightly a few > times during the dormant period, and half is not, depending on (1) > whether the bulbs are in pots or directly in a raised bed, and (2) the > climatic conditions they have adapted to in nature. The pots I use are > either terra-cotta or plastic mesh (used for hydroponic and aquatic > growing), not solid plastic. > > Some bulbs seem to break into growth in response to temperature, and > others more to moisture. Some may just be "timed." This year we had > significant rainfall in September, which is unusual, and some fall > crocuses flowered a month or more earlier than they did in the roofed > bulb house. > > Jane McGary, Portland, Oregon, USA > > On 12/19/2019 11:50 AM, Cody H wrote: > > This year I put my summer dormant bulbs (both South African and > > Californian) in their pots against a sunny south-facing wall, where temps > > probably break 100F at least 15 days during the summer. In that location, > > they receive no rain, and I didn’t water them at all, even the > (relatively > > few) amaryllids. I just repotted them all and most are looking very > > good—healthy roots and not dessicated, and many are beginning to grow. > > > > The year before I kept them in the basement, where the temp rarely hits > > 75F, and although the bulbs looked fine when I reported them that fall, > > many of them failed to break dormancy that winter and I lost quite a few > to > > rot. I will be putting them against that south facing wall again this > > summer! > > > _______________________________________________ > 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/…