Nice plants, mine are all started from seed as well. No lights, just MOTHER Nature... I start my seeds during the last week of Feb, once they crack open it's placed outside in greenhouse (1 gallon pots) We had a pool put in this spring, started in Feb and I didn't get my seeds started and greenhouse going till after construction was almost finished.
My seeds are just regular seeds, don't put into box until they sex, about 5 to 7 weeks after germination. In a normal year I'm all thru with planting by the end of April, this year was more like the first of June so I lost 6 weeks of vegging. Built new boxes this year, 6 foot by 6 foot and 20 inches deep, plus we till the soil down another 10 to 12 inches. Hope this helps?