I am growing somewhere between 200-350. I really have no idea at this point because I have not counted yet what has survived to this date. I have young seedlings in cups, seedlings in 4 1/2 garden areas (I am moving the rest from the other 1/2 area), and named/registered daylilies in 2 raised beds as well as pots. I guess I should make an effort to count them all. I'm almost afraid to.
The true story is that I hope most of my named daylilies survive, though I've lost 3 so far since I first started acquiring registered daylilies less than 2 years ago. I've had many, many seedlings, but the majority do not thrive here. (I suspect genetics plays a part in that and less than ideal conditions is the other issue.) So, my thrive vs. struggling daylilies pretty much weed themselves out of my yard.
What I hope it presents in the future .... is the best I can grow here with what I have and then use those in my hybridizing efforts. It's all trial and error for the most part. I have noted that spider forms seem to do well here if they are grown from seeds. Probably due to less leaf area to be fried in summers and/or attacked by pests/disease each year.
I guess I need to do a count.