-273.15C -459.67 F absolute zero temperature
-50 C         -58.0 F  
-20 C           -4.0 F  
-10 C           14.0 F  
2.22-1.11    36-34  °F   , Light  Frost
0.56-1.67  33-29  °F    , Hard Frost
 00 C           32.0 F freezing/melting point of water
-2.22          28  °F>4hr  , Hard Freeze
 05 C           41.0 F  
 10 C           50.0 F  
 20 C            68.0 F 
 21 C            69.8 F room temperature
 30 C           86.0 F 
 37 C           98.6 F average body temperature
 40 C         104.0 F 
 100 C       212.0 F boiling point of water

  
Tomatoes (Solanum lycopersicum) 
tropical perennials grown 
as annuals temperate climates. 
Anytime: Tomatoes 32 or < Kills,  
Daytime:  
<50 degrees, survive but not yield. 
<55 degrees stunts,decease yield., 
55-90F, Production 
65-75, Best growth 
70-80 Germination 
>90F, No Production