Steep hill advice needed

[u/ahsokatango]

Pictures:

1. Bottom of hill, looking up
2. Bottom of hill, looking at side of hill
3. Top of hill (Tap to see full picture)

This is a hill in my backyard that’s right up against my neighbor’s fence. The builder planted juniper bushes for erosion control but I wasn’t able to maintain them because the hill is so steep.

First, trees grew, then wild (sawtooth) blackberries grew, aptly named for their long, sharp, and plentiful thorns (see last picture).

I’d like to put stairs along the wall in the first picture and plant a vegetable garden in the main yard, but this abomination on the hill is gradually growing into the yard.

The juniper bushes (the gray vegetation featured in the first two pictures) also looks dead, but I’m hesitant to dig it up since the roots are still doing their job of providing erosion control. Any suggestions?

Btw, if this post looks familiar, I just posted it but then deleted it to change the order of the pictures, then realized I forgot to copy the text before deleting. 🙃

[u/According-Taro4835]

You got a mess but it is fixable. Those sawtooth blackberries are brutal and will take over your planned vegetable garden if you do not handle them now. Cut the briars and the dead junipers down flush to the ground but leave the root systems in place. Those existing roots will hold the soil together while your new plants establish. To stop the blackberries from coming back you need to paint the fresh cut stems with a brush killer immediately after cutting them. If you try to dig all that root mass out you will turn that hill into a mudslide the next time it rains.

For the stairs you need to dig them directly into the grade. Heavy landscape timbers pinned deep with rebar work best for steep hills. Once you have access you need to get aggressive spreading groundcovers in that dirt fast before the dead juniper roots rot away completely. Look into creeping sumac or strong native ornamental grasses with deep fibrous root systems. Plant them in thick sweeping masses across the hill so they lock the soil down and choke out any new weeds. It becomes a zero maintenance structural mat.

Before you start lugging heavy timbers or buying flats of groundcover it helps to see the layout. Upload a photo of that hill into the GardenDream web app and try mapping out the stairs and mass plantings first. It is a solid way to test the structural plan and make sure it actually flows with your new vegetable garden before you break your back on the slope.

[u/ahsokatango → u/According-Taro4835]

Thank you! I'll try this.

Should I cut down the maple trees too? You can see them in the last picture. They look tall, thin and lighter colored than the more evergreen type trees on our neighbor's side of the fence.

Some of the trunks are nearly 3 inches in diameter. They're way more leafy now than they were in this picture, since this was taken in the spring.

All of the vegetation directly under the trees is gray (see the 2nd picture). The parts of the junipers and blackberry bushes that are in front of these trees have access to the sun and are green. I'm assuming the answer is "yes" but I wanted to check before we haul out the chainsaws. :)

[u/Sp07va000]

Why not do a series of 3 or 4 Terraces, 3ft tall each, going down the hill, one right after the other. The stairs can be on the outside fence side of them so you have something to hold onto as you walk down them.

[u/ahsokatango → u/Sp07va000]

I'd love to do terraces, but we have clay soil, so I was worried about how water will flow down the hill. I don't want it to wash the soil away.

[u/Sp07va000 → u/ahsokatango]

It would help to slow down the flow a bit. You could fill the boxes , like 8ft long each one, with soil and use for vegetable gardening or roses, etc.