Hi Olin, To further clarify the fruit temp situation, I have copied a section from Jeff McCormack's catalog. >>Daytime temperatures should not exceed 90 Deg. and night temps should drop below 70 Deg. but not lower than 55 Deg. Optimum night temperature is 59 -68 Deg. At 40 Deg. some varieties show tissue damage not readily visible.<< There are some varieties that seem to stretch the limits considerably. I haven't really experimented with the cold limits but I do see definite advantages to those varieties listed on my web site under "Hot Weather Specialties." The URL is < http://www.heirloomtomatoes.net > As expected, the Siberian types do seem to set fruit at lower temps but, surprisingly, they seem to exhibit the ability to set under higher temps as well. On the high end, it seems that temps dropping to 70 for only a short time will allow fruit to set also. Only a short time in daytime above 90 doesn't seem to be very harmful either. The crux of the matter seems to be that there are about a dozen good heat setters which I have enumerated on my web site. Primary among those are Super Sioux, which Steve Parton of Melbourne Australia reports setting fruit under 115 Deg heat. Homestead 24 - F seems to be the best known in this category. Porters' Pride from the old and respected Texas company by that name, was bred for the Texas plains and is still a super hot weather 'mater. "Stupice" reigns as the premier cold setting variety with "Kotlas," "Grushovka, " "Mountain Princess" and "Early Siberian" also good choices. "Oregon Spring" burst on the scene a few years ago as a cold weather setter and it did set fruit, but that fruit tasted even "worserer" than the super market types, IMHO. See Carolyn Male's new book that she promises to have out in June. I am trying "Sophie's Choice", "Prairie Fire" and "Clear Pink Early" this year. Good gardening, Chuck Wyatt