I don't know if there have been any controlled studies about germ rates at lower vs. higher temps. All my info on this has come directly from this chat room, and all has come from Subcool, so it's a one-source concept. However, there is something intriguing about it, even if the evidence at this point is anecdotal. In one of the last 10 Weed Nerd episodes or so, Subcool was talking about someone he knows complaining about having so many males with TGA seeds, while Sub has a lot more females. The difference was the Sub was germinating around 70 or 72 degrees, and the other guy was germinating in the 80s.
My own (limited) experience is in line with this. I first popped two Jillybeans at about 80-85 degrees last summer. As an impatient first grower, I was THRILLED when they broke up through the rockwool cube in 2.5 days (I do hydro). Not so thrilled when 6 weeks later I discovered they were both male. By then it was October, and I germinated two more Jillybean seeds, this time at around 70 or 72 degrees. They took much longer to break up through the cube. Almost 5 days, and I was worried about them. But happy as a clam when they were both females.
So I'm thinking why this might be the case. What's the advantage to the plant in nature, especially for one that can self-pollinate? Why would there be a hormonal change in the seed to create females over males, or vice versa? I figure that the females grow a little slower, and their peak pollination time is 4-6 weeks into flowering. So let's say there's a field of plants, all leaning toward females at first because outdoors they germinated in the spring under cooler temperatures. If another plant germinates later (warmer temps) it makes sense that it would be male, because it grows a little faster and can pollinate at around 3 weeks of flowering. So the big field of females (maybe a few males in there) just needs one or two late-germing males to pollinate enough of them to ensure the survival of the species. Therefore it makes total sense to me that warmer temperatures for germination would throw more male plants, just in case all those females from the earlier germination were going unpollinated. And then, if there still is no pollen, the plant has one final chance at a new generation by self-pollinating.
Just my conjecture, not scientific at all. But it does make sense to me!
awesome gesture...+rep!
I am happy to help and I wish more people would be more about weed, less about greed. + rep for the kindness man respect.
