My 3 years old female(2008) gave birth to 29 healthy babies,one slug,2 still born!!She mate in mid March with a wild caught male from the exact same location....It took four and half month of pregnancy this is very long!!
The snake was in an aquarium with a basking light,from March to July a 25 watts sun glow bulb was used and the temperature was near 22-25 celcius From July to August a 40 watts sun glow and temperature 22 to 29 celcius...
For northern species of garter snake basking light is needed I think!!