Hi Diane, I'm sure I get more sun in winter than you do but of course it gets much colder here. To deal with that I have a large (300 gallons) tub of water as a heat sink; also, the greenhouse is attached to the south side of the house. In any case, it only goes down to freezing but not below, except near the glass. For you I would think a greater concern would too little light for growth, bad for geophytes but no problem for summer-growering winter-bloomers like camellia and cymbidium. A fair number of the species I describe fall into this category. I hope that helps, and I'll be interested in further thoughts. Jim Jones -----Original Message----- From: Diane Whitehead <voltaire@islandnet.com> To: Pacific Bulb Society <pbs@lists.ibiblio.org> Sent: Thu, Jun 7, 2012 4:37 pm Subject: Re: [pbs] New book How applicable would your information be to those of us who rarely see the sun in winter? My unheated greenhouse manages to keep itself frost-free but if the sun does come out, the temperature may go up only a degree or two. Diane Whitehead Victoria, British Columbia, Canada cool mediterranean climate moderate dry summers, moderate rainy winters 68 cm rain (27 in) On 7-Jun-12, at 1:08 PM, James L. Jones wrote: > The book presents detailed information on operating a greenhouse > that is heated by the sun alone and on choosing a satisfying array > of off-season bloomers that do well under its conditions,