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Is it too late to plant Cosmo seeds outside?

Trenton, MI(Zone 5b)

Ok, so I'm not a beginner. But I've always started my cosmo seeds inside.
The ones I sowed this year did not germinate. But I've decided I really want them.
Soooo, here's the information ... our last frost date was May 15th. Usually you sow the cosmo
seeds outside as soon as the soil is workable. If I sow them outside now will they bloom before the end our our summer?
Detroit, Michigan zone 5/6. I'd appreciate any infor.

I've finally dug an area out in front of the garden shed and would love to have the cosmos there.
Thanks, sharon

Thumbnail by toofewanimals
Shawnee Mission, KS(Zone 6a)

Looks like it should be fine.

Traverse City, MI(Zone 6a)

This is not at all meant to discourage you, because I do live further north and that may very well be the difference. Last year I started some cosmos seeds in a full sun garden during the second week in May (it had been warm early), anyway the plants and foliage did great, but they did not have as many blooms as the ones that I had started inside and a few of them had no blooms at all. Same garden, same seed packet, same soil, and same food, only difference was when they were started.

Shawnee Mission, KS(Zone 6a)

Intereseting. I always throw them in the garden or let them reseed. No problems with the amount of blooms. I did lose them earlier last year because of the weather issues that we had here in KC. Wet spring and then dry, hot fall.

Traverse City, MI(Zone 6a)

I may have jinxed the little guys, because of how thrilled I was with their size and apparent lushness after having been started late. I'll throw some in the garden today and see what happens this year, then check back in.

Trenton, MI(Zone 5b)

I think I will do both this year ... buy a couple plants from a nursery and also throw some seeds out. Thanks for all of your imput, I really appreciate it. :o)

Troy, NY(Zone 5b)

Sometimes if the soil is too rich cosmos will get huge but not flower very much. You can still throw seeds in with no problem. They will bloom later but if you don't deadhead them in the fall they will reseed for next year.

Traverse City, MI(Zone 6a)

Oh cool, thanks so much, I probably added too much manure in those spots when I planted them, and of course the ones started inside didn't get anything but a very light seed starting mix for their first month of life. So then when the direct sow guys were not getting blooms like the other guys, I gave them extra. They were like feathery shrubs with no flowers.

Gainesville, GA(Zone 8a)

What a darling shed and arbor! I started my cosmos in soiless seed starter in the greenhouse where I didn't have lights ( I will next year!) They came up like crazy and I re-potted them in 3" pots when they got big enough...or should I say tall enough. Those are some of the scrawniest plants I've ever seen! Hah! but such darling little flowers about the size of quarters. They were supposed to be bigger but I know I didn't provide supplemental light and that's probably what made them so scrawny, right? And when I re-potted them I only put one or two of the seedlings in each pot and they got taller but still scrawny. When I bought some coreopsis from a nursery there were lots of little plants in the same pot and that's what I should have done with my cosmos, right? Such pretty little flowers, I would like to learn how to do them right so I can have a nice stand next year. To thicken up the little patch I threw some more seeds in with the plants I already had hoping they will be more dense. Any suggestions?

Traverse City, MI(Zone 6a)

I had some cosmos from a local hardware store packet that were orange and yellow flowers and those guys had smaller blooms (2"dia.) than the psyche mix that I get from Park's(3"dia.), but the plant itself was still over a foot tall and about a foot in diameter. I have gotten flats from the local farm markets of the same pinks and whites that are in the Park's mix, that got a little taller and narrower, but had more flowers. Up here they take awhile to fill out, and are going along nicely by mid-summer, but your growing season is longer and warmer. I'll bet yours will fill out given time. Someone with way more knowledge than me is likely to give you actual advice rather than just zone 5 observations:-) Good luck.

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