Mxk3, too bad you haven’t gotten any answers to your question. I don’t have any experience with growing China Asters, but finally gave in to temptation and ordered seeds. I’ll be trying them in the coming months. I’m in such a hot and dry climate, that I hope they do alright here. I wonder if there’s something that could help prevent aster yellows, maybe pretreating the seeds with something? I’ve read that it’s best to grow them under row covers, but that’s not a realistic option for someone like me. I just want to grow some in the garden for personal use. Apparently, it’s the leafhoppers that spread the bacteria that causes aster yellows. I’m not very familiar with leafhoppers, but I think finding a way to control those would prevent or at least, reduce the problem. Lisa

I ended up picking up a packet of seed off the rack at the local store at 40% off (yes, it was packaged for 2019), I figured what the heck I'll give them a try. I could use row covers until they're ready to bloom, thanks for the tip. They'll be for cutting, so way back in the veggie garden where the row covers won't bug me, and I have to use covers for other stuff anyway.

My problem with China asters is that they are difficult to germinate and slow to bloom. I have not had a problem with aster yellow (on them. On Echinacea, but not on them). I have to think their botanical name Callistephus chinensis is why it's not a problem.

I've grown Astoria Mix for years... it self-sows for me if I don't deadhead. Great cut flower and never had a problem with aster yellows (knocking wood!).

I have a few different pkts, two from Floret and one from Johnny’s Seeds. Do they need to be germinated indoors? I assume that most people start them indoors, grow them under lights, and then transplant them outside. They bloom at the end of summer, right? I’m having a hard time deciding when to start mine. Since I’m in such a warm climate, starting things indoors isn’t strictly necessary for anything, but I enjoy the process.

I know nothing about row covers, since I figured they were used for colder climates. Plus, I want to have little clumps or sweeps of China Asters here and there.

Party_music, since yours self sow, do you just leave them alone to grow uncovered? I wonder if I could start some directly in the ground, although every site I’ve read, says not to. How do you think they’d deal with So California’s hot, dry summer and fall? I’m in love with those blooms, but they are never seen growing around here. I wonder if they could be grown like snapdragons here? With our temps, we grow snaps all winter and spring. They can’t handle our summer and early fall conditions. Maybe I better see if they are tender or hardy annuals. Something tells me they’re tender, so growing them to bloom during the winter wouldn’t work. More research to do, I guess!

Rob332, think a weak GA-3 solution would help them germinate? Lisa

Lisa, I've always direct-sown asters by scattering the seed very early in the season... I'm in z5 with a last frost date of June 1 and I try to scatter them out in March or April.

And, yes, I just leave them uncovered. I think self-sowing always works best if the soil surface has been raked or roughed-up before the seed goes down.

Hmm, you two are making me wonder if I’m already too late to start my seeds. The temps are forecasted from 68-75F during the day, to 47-50F at night for the coming week. I totally agree with you Patty, about raking the soil before direct sowing. So many people think “throw and grow” means just that, but raking up the soil makes a huge difference. After scattering the seed, I also often walk over the area to give good soil contact.

Maybe I’ll rake up a small area today, and direct sow just a few. I’ll store the majority away for late Fall and try again. I sure wish I had sown them a bit sooner. Thanks for the tips. It’s always a little tricky sowing cold hardy seeds without a real winter. Most of the information out there pertains to areas with freezing temps and snow. It’s difficult to adjust advice for my climate. Lisa

We've got snow on the ground with another dump expected...gotta go the indoor route this year.

Mxk3, I just can’t imagine that! Here I am worried about my cold hardy seeds germinating due to today’s temperatures. All of a sudden the temps soared to nearly 80F today! It should go down again soon to the high 60’s and low 70’s, but these yo-yo temps are crazy.

At least your cold hardy perennials should be happy. My hardy geraniums always struggle because they don’t get enough winter cold. Lisa

Yea, there's no perfect place, is there. I don't love the cold, but I really hate high heat, so I think it's not so bad up here :oP (actually, I live in a beautiful state...cold at times, but beautiful).

I agree there’s no perfect place, not for gardening, and not for many other reasons. I too, can’t stand the heat, and we get plenty of that, from about mid June to mid November. I know MI is beautiful. I bet you don’t have the huge crowds and traffic problems we have in San Diego County, CA. Every bit of land is being built upon, and there’s very little natural landscape left. If I had a choice, I’d move somewhere like Oregon. There’s just too many people here. Lisa