Mine sprouted in two weeks last year. I'm getting a late start this year, so nothing yet. Lea

Good question... The datura tatula(?) I started, germinated within a week. The triple yellow and double purple that I started 3 and 4 weeks ago still haven't germinated...

Cheryl

OK, I tried 3 times. Nada, nothing, zilch. Until yesterday when I spied one of the (soaked) seeds I had just put out like a day or two before! Then I spied the ones that I had put out a month ago and the ones I had done probably 6 weeks ago...all with seedlings! I did absolutely nothing different...but the weather has been exceptionally warm this week...mid 80's. So my guess is that if you could get your seeds up to that temp you would see very fast germination.

I just went to put a small space heater near the datura and I saw 2 little sprouts coming up. I'm so excited. I did put the heater on just to see if it would speed things up a bit.

I've grown it for the past few years. It is very erratic about germination. Putting it on a heat mat does seem to help. But it will vary a lot, and don't give up too soon. A few seeds will jump right out of the ground, and the rest...will come in their own time.

Mine sprouted in a little over a week but that was in a greenhouse where it was above 70 deg. during the day. This is my first time growing them and I am trying all kinds that I got in trades, white, purple/white, double yellow and double purple. Wish me luck!

Mine Started in about a week using the baggie method and placing it near the heating vent.

Using a heat mat, I've had 3 out of 5 come up in a week. Nothing from the other two yet. Sounds consistent with everyone else's experience.

After waiting almost a month before my triple creams came up, I decided to start some white ballerinas. Again nothing after 2 weeks, so I started another batch (same exact thing I did with the triple creams). It has been consistently 75+ degrees down here and still nada. At around the 4 week mark, they all came up together again! Don't ask me why! But now I have plently to share or trade! I've got a couple of triple creams in the ground all ready. They've only got about 6 leaves but I wanted to get them out and established before the real heat sets in!

Datura seeds need soil temps between 60-70 degrees to germinate. I WS mine and once the temps warm up, the seeds germinate fine. Within in 2 weeks of germinating outside, the seedlings too off like a rocket and grew by leaps and bounds. went from sprout 2 6-8 inches in 2 weeks.
I found the single white flower germinated about 3 weeks earlier than the double purple, lilac lefleru and black currant swirl. Once the germinated they all grew the same.

Also found that you can control the size of the plants by growing them in various size pots. The smaller the pot, the smaller the plant, but bloom just as well as a huge plant growing in the ground.