[tomato] Tomato Fruit Set & Hot Weather

ChuckWyatt/Md/Z7 (Tomato@GlobalGarden.com)
Sun, 25 Apr 1999 08:57:18 -0400

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