Just curious when is the latest in the fall that I can seed a new lawn here in Vancouver. Zone 7?

We're in a warmer climate than you are in BC, & we got a late start with our new lawn... planted just 3 weeks ago, as the weather started turning colder. It has been getting down to about 39F at night & it took 3 whole weeks for the seeds to sprout, but over the past several days our yard has started looking like a Chia blanket! (I was real worried about 10 days ago, when nothing had sprouted yet & it rained in torrents for 2 days! I thought for sure all our seed would be washed down to the low side of the yard... & beyond) , but apparently it stayed where we put it!

As far as I've ever heard, early fall is the best time for planting grass seed, as the soil is still warm but daytime temps are moderate, & keeping the seeds wet isn't as much of a problem as it might be during summer months. (You also won't be as likely to cultivate as many weeds along with the new grass, as with spring lawn planting.)

I think the big deal is that the warmer the soil, the better/faster the germination of the grass seed, so even though we're not likely to freeze here, I think that probably some of our seed won't stay viable in these cooler temps... we'll have to wait & see/not sure exactly how that works!

I know that you have some pretty cold winters up there, & I'm not sure how hardy brand new grass is... whether it will withstand freezing temps or not, but if I were in your shoes I'd go ahead & give it a try! (What have you got to lose... a bag of grass seed? If it doesn't 'take', you can always do it again in the spring!)

With any luck, The Plant Doc (Mike) will show up here... he knows a lot about stuff like this, & I trust his advice.

Unless you think you'll be into snow & freezing temps anytime soon, you might also want to use a starter fertilizer when you plant your seeds, cuz heavy rains can leach nutrients out of the top layer of soil, beyond the reach of the new roots. (Use your own judgment, but I suggest that you read what Mike has to say: "Fertilizing lawn can be a bit tricky this time of year" ...his is the 4th post in that topic.)

Good luck. If you decide to go ahead, I'd be curious to know how a late planting worked for you there in BC, so keep in touch!

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