Question
I'd like to grow petunas from seed, I live in Denver, CO and have just purchased a grow light, blue spectrum and I have a florescent lamp for sprouting... I've read a little from Morgan-Thompson Seeds... and wondered how long does it takes? any suggestions would be greatly appreciated, Thanks, Janet

Answer
Janet,
Start your petunia seeds 8 to 10 weeks before you can plant them outside in your area.  Sow the seeds on the surface of seed-starting mix (get mix wet BEFORE filling your seed trays - sow seeds on moist mix and then water briefly - do not cover because petunias need light for germination. I usually cover my trays with clear plastic wrap and check daily for germination - remove plastic at first sign of sprouting.  Petunia seeds take between 7 and  21 days to sprout.

Keep the young plants about three or four inches away from the lights - move lights up as plants grow.  If you keep a fan on the young plants for a couple hours a day that will help make them stronger.  Pinch tips of plants when they about three inches tall to encourage branching. Don't fertilize until very close to time you plant them outside.

Be on the lookout for whitefly and aphids - two insects that are common on indoor annuals.  Hanging yellow sticky whitefly traps around  your flats might be a good thing - traps insects and alerts you to the problem early on.

I hope this helps!
C.L.