Iv always been told...read..and seen for myself by leaving the lights on that long inside and taking them out in early April will stunt your plant ...I tried matching the suns hrs before but the plants were already sprouted and they done way better than the ones I left on for 24 hrs and 18\6...I'm a firm believer that the more u mimic nature the better results you will have....if I could I would have them outside now....I got a late start this year ...usually u plant on valentine's day but I couldn't get my supplies till last Tuesday