Jute erosion netting

So would we shape the sand how we want, then cover it with jute erosion netting, then place topsoil on top of the netting, and cut holes in the jute to plant things? Or do we shape the sand, try to get topsoil to stick to it somehow (maybe make it into mud so it will stick?), and then put jute netting over both, cut holes in it to plant stuff, and cover that with mulch?

Forget for a moment about what you could or should do. When starting you had to have some vision or goal in mind, or you would have just left the hill alone. What were you trying/hoping to accomplish? We need to see not just the hill, but the surroundings. Step back a ways and give us a big view. Or take it in slightly overlapping shots while YOU STAND IN ONE PLACE with the camera.

@Yardvaark It's my partner's house. I don't think he thought this through to the very end when he started. His only goal was the "cut back the hill for more flat lawn in the back and use the sand to make the lawn level up front".

I can take more pics when I'm there next time. I wish I had before pics so you could see the difference. This used to be a very closed-in mostly grassless pine and hemlock grove with a house plopped down on the edge of it. There were trees everywhere, very little sun reached the back (west) or side (north) of the house. Once he got the trees removed (some of the big 100-200 yr old pines were professionally removed, but we've done the hemlocks ourselves), the grass started growing, and once he saw he could have a real lawn, he hasn't stopping digging and moving the sand around. It started as digging out the stumps, and it's been non-stop digging anything that can be dug and spreading the sand in other places for over 4 years. It's only now that he's gotten close to the line of driveway reflectors that he used to mark where he wanted to stop digging back to that he's considered that a sheer drop off of sand under an azalea that is floating at eye level (with roots sticking out at chest level) isn't going to be easy to landscape.

He saved the last couple of Hemlock trunks we took down so he has 6-7' logs he can possibly use to make a retaining wall, but I'm getting the twitchy (skeptical) eye looking at them. I'll take better pics next time I'm there. It's truly a landscaping nightmare.

He will not invest much money into landscaping. It took 5 years of deliberation to buy the birch trees he'd wanted all that time, and only then because they were discounted at the end of the season (the road is called Birch Lane). He refuses to buy any annuals (waste of money, he says). Perennials need to be 95% sure to survive and come back, so he will only buy 1 or 2 plants a year until he's sure it will come back (so creeping phlox, virginia spiderwort, chives, chocolate mint, periwinkle (which is invasive but he doesn't care), hostas, solomon's seal, lily of the valley, azaleas, rhododendrons, maidenhair ferns, lilacs, and day lilies are the only proven plants so far - most of them shade plants and he's reducing the shade more and more). The exception is if I can find it for free (like on freecycle) and the western red cedars he planted for privacy screening after we removed the hemlocks from the back. Something that can be started from seed would be great since seed is cheap, I can just buy it for him and he's not stressed out about wasting his money on things that won't be successful - with a caveat that he's also reluctant to water things as much as they really need because "water isn't free".

So, that's what I'm working with, and I admit I am pretty over my head right now because I have no idea how to deal with the sand. The erosion problem is, in my mind, a serious one, but apparently the town doesn't mind that part of his hill (in the front, the road frontage, not back here where this project is) washes out into the road when it rains hard, so we're concentrating on making the back yard nicer since the front hill is basically impossible to fix without a huge investment in retaining wall (which he will not do - he already invested $30,000 in replacing the windows and he doesn't plan to keep this house since it is just his first starter home). I'll get more pics!

Jules, what would help a lot is to take pictures that show a large amount of surroundings. It's very hard to orient one's self with close ups of dirt and weeds. Especially, try to get the house in the picture, too, with the hill, so we can have some perspective about the scale of things. Right now, it looks like a hill of dirt in no man's land so it makes one wonder, "Why bother?"

Arctostaphylos uva-ursi, Bearberry could be perfect for this slope. Hopefully it is a common groundcover in your parts which could make it Cheap and easily available.

https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=j380

I agree. Bearberry sounds perfect. You may need to add little or no topsoil.

@Yardvaark, I added more photos to the post, as you requested.

I see how a small "cliff" has been created. You guys would need to put some soil back to create a smooth slope, or add a retaining wall. But I think slope would be your better bet. Anyplace else in the yard you need to get rid of soil?

@Yardvaark yes, we plan to build a new retaining wall and fire pit down in the cliff area, but we need to plant the part more behind the back door, the original sloped area I posted. We got some juniper cheap at Walmart to try (it was on clearance) and we will keep an eye out for the bearberry.

Hopefully, it's a low growing juniper. You might try bearberry from seed as that is a known possible way to get it. Ebay is the go-to place for oddball seeds & plants.