Low temp issues?

[deadhead77]

Jeez I went away for 3 days...the heater I was using had issues and it looks like temps went down to 50f for four hours each day. The plants are in veg. They look great. There is very minor leaf folding. All is green and looks fine. Should I expect root damage or anything? Thanks

 

[w3rds]

For the first 3 weeks of my current grow, my nights hit low 50s. Im at week 8 right now and they are looking just fine.