Seeds—how late is too late?

[WNC Bonsai]

So this spring I planned to start a bunch of seeds. However my wife just inserted a one week trip into my shedule the end of June, so I won't be around that week for regular care. So it appears I need to delay planting until July 2-3. The good thing is the weather will be nice and warm by then so the seeds won’t need bottom heat outside. I am starting dawn redwood, pseudolarix, Jap larch, and tridents. Is July too late to start them?

 

[Wires_Guy_wires]

Nah, I think you're good. I did some late pines last year, they all seem to do fine with a short summer.
Sowing late can help you reduce the initial internode length. It can be a strategy even!

The only issue I see is that they might germinate in the fridge early, and you'll be planting seedlings instead of seeds. But that also depends a whole lot on the moment you start the cascade.

 

[Pitoon]

When you say starting them in July are you talking about planting the seeds or the seeds germinating? Planting seeds I think you would be pushing it as it could take a month or two for them to germinate. If they are germinating in July then I would say you have a chance for them to put on a couple true leaves before it's time for them to go dormant. You need to plan in reverse when planting seeds if stratifying in the fridge.

 

[Dav4]

I've started JBP seeds as late as late July with good results. Make sure you've properly stratified the seeds whenever you do plant... I know the tridents require 3-4 months for good germination rates

 

[WNC Bonsai]

Yes, i plan to stratify on a schedule to take that into consideration. I just don’t want to have seeds germinating outdoors while I am gone or even worse have seedlings sticking up above soil level and have the soil dry out. I have read that the dawn redwood germinate best if soaked for about 5 days with no stratification. They were collected locally so may not be viable anyway. However the others are coming from Sheffield’s Seeds so I will still have plenty of time to get them in the fridge in advance of the desired planting date.