You'd be best leaving this project for spring. It's too late in the season now to get very good germination if you're seeding - you'd need to overseed again in spring anyway to fill in and even things out.

I'd consider some sort of groundcover for under the cherry rather than the Eco-turf. The seed blend of Eco-turf is more suited to a sunnier situation and will be sparse and open and prone to weeds if attempted in much shade. Additionally, Eco-turf does need to be mown occasionally and cherries are notorious for surface roots that make lawns and mowing challenging and generates scraping and scarring of the roots - cherries have enough problems in our climate without creating open wounds for diseases and insects to invade.

One of the primary reasons - outside of neglect - that lawns fare badly around here is poor soil conditions. You will have much better results if you prepare the soil properly for the seed bed and that involves removing existing weeds and amending to get rid of the compaction and increase fertility, which is typically low in lawn areas. Overseeding in your situation will only result in a weedy lawn.

WSU has extensive literature on selecting, preparing for, planting and tending a new lawn, including info on Eco-turf. You might spend the winter months boning up on this before tackling this project in spring.

BTW, you need to avoid walking on a newly seeded lawn until it has germinated and is about 2" tall - that's going to be several weeks in decent weather and growing conditions.

Here is a link that might be useful: WSU lawn care publications

Sod, you might get some roots on until December.

But seed - no way to get anything that will stand up to winter, if any germination occurs at all.

Too cold for germination now, and all this rain will literally wash the seed away. One year I seeded a lawn right at the end of October, the tail end of the lawn seeding season and followed immediately by heavy prolongued rains, it came up all right for the most part, kinda sparse, and you could definitely see little green 'rivulets' of grass running downslope from the lawn edge ...

Creeping fescues are probably the most shade tolerant of grasses but still won't be all that vigorous under cherry trees. However not much else you can plant that will take being walked on and sat on. Have you thought of paving stones under the trees for your sitting area?

Invasive grasses are the bent grasses and creeping fescue. Tall fescue doesn't creep all that much but it doesn't like our winters either, too wet and dark. Ryes are ok, don't creep all that fast. Keep in mind that the healthiest lawns tend to be made of creeping grasses that can fill in their own bare spots without needing reseeding, and bare spots are inevitable in any lawn. I liked a blend of creeping fescues with rye grass and white clover for durableness and low maintenance - the clover reduces fertilizer and water needs, and creeps to fill in bare spots. So does using a mulching mower. I liked the eco turf too. Mostly dwarf fescues I think.

Any newly seeded or sodded lawn needs a period of time with no foot traffic. Couple weeks for sod, as long as several months for seed needing to tolerate heavy dog traffic.

When you suggest that you will be walking over the area several times a day -- this will wear a path in even an established lawn. Should you plan a path for the walkway area? This might be something to occupy you until it is time to seed.

Thanks for all the info. I will wait. I will be asking an arborist to look at the tree, so maybe I can get ideas about covering the roots then. I would like grass, because it's an old cherry tree and it would look a little like an old orchard that way. But that's just romance. I don't have a sheep to keep the grass short without mowing anyway!
Laura

Not sure where you are at. If you don't have an arborist already picked, you can always search online for the

International Society of Arboriculture

Their website has an option to search for arborists in your area by zip code or by city.

It shows whether they are certified in utility line clearing or as a Certified Arborist, or maybe municipal work too.