You want plants that have strong and/or deep roots, but not invasive roots.

Ornamental grasses, especially along the bottom, are good because they will hold the soil and you can find them in any imaginable size (the really beg ones may shade your roses). Crape myrtles also shade the roses and they have invasive roots, so I would stay away from them (Plus, it is not fair to a plant to "keep it small;" find a plant that doesn't grow big). Nandinas are good and give you year-round color. Also [carpet] junipers. Lirope. Small hollies.

What plants are native to your area? Some regions have deep rooted grasses that will, if allowed to grow tall, put down deep, deep roots. If you have to cut them (and your city may require it at least yearly) they will still be well-adapted to your area and not require constant attention.

Rosefolly

Here is a link that might be useful: Native grasses of Oklahoma

I have a hill in the front of my house where I mixed perennials with roses. I chose plants that spread fast, so I kept everything pretty short to make it easier to maintain. My favorites here are nepeta (perfect for roses), blue oat grass (helictotrichon), daylilies, snow-in-summer (cerastium) and geranium macrorrhizum (fantastic for dry shade), and sedum dragon's blood. I bought most of these perennials from Bluestone.

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Of course, your hilly situation might be very different from mine, just thought I'd share my hill just in case. You probably don't need a crosswalk sign :)

Maureen

That is really a lovely hill garden. I'm quite impressed.

Some more information would be helpful. Is this slope by the creek? I'm with rosefolly in using natives, especially by an environmentally sensitive area like a creek or other waterway. There are many native grasses to your area that put down deep roots, I would go that route rather than the "ornamental" grasses that are not native to your area.

You may need to put up temporary erosion barriers until the supporting plants take hold. Any kind of barrier, whether landscape timbers or conifer prunings or what have you just to slow the erosion process, especially before the spring rains come.

I'm wondering why the city cleared out all the brush but that is another matter altogether.

Rosefolly, thank you for the link to the grasses. I need to find out what else has deep roots that will hold the soil.

Maureen, that is about the slope of my yard now. It used to have so much more soil, but it can quickly erode if nothing is done. I forgot about sedum, and that will maybe hold the soil and look pretty.

That bed is very pretty.

Catsrose, I love crape myrtles. I will plant a number of them. Once I cut what I have, they will create many more for me. Right now I have 15 of them. Every year I cut them back, and they bounce back just like a rose does.

Thank you for the suggestions. I am making a list since I am not that familiar with many plants.

Sammy

Linrose, the entire area is a creek built for flood control. The area around the creek became too full of willow trees and ugly cottonwoods. They haven't been through for over 20 years, and when they came, they had giant machines that ripped the trees out of the soil. They then drove them up the slope and shredded them. It was quite a sight, but I was at work and couldn't see it.

When they pulled out the trees, they just took the dirt with them. Also that manner of ripping them out, and the heavy machinery made a lot of the dirt fall to the bed. I will take a picture of it.

Technically we don't own that area, but we, the neighbors around us and across from us take care of the property as if it were our own. The result makes it very pretty.

Sammy

Sammy, this might not easily apply to your situation and might be too much trouble too, but just in case it might work for someone...

We once had a large amount of dirt added to our yard to make a long berm, which, looking at it from one side, was maybe six feet high and very steeply sloped on that side. But we ran out of dirt before the berm was sufficiently wide and more gradually inclined on both sides, so the steepness of that slope, especially on one side, was a problem for planting all the various plants I wanted to put there (mostly azaleas & rhododendrons).

What I did was to create multiple shelves by adding more dirt at each spot a new plant was to go in, making the dirt below it even steeper. All along the surface below that new plant, I stuck into the dirt a ton of twigs from our deciduous trees, mixing them up with the leaves from those trees, leaving the twigs to stick up and fan out quite a bit with leaves resting against them. ("Ton": maybe one twig with its small branches stuck into the dirt every 5 inches or so in each direction.) Then a 3-4 inch layer of mulch to help stop the most pounding aspect of the rain when that sometimes happens. The mulch was somewhat intersperced with the hardwood leaves in many spots. The twigs eventually rot away but by that time the azaleas (or whatever) have sent out their roots all along the surface to help hold the dirt in place.

I do think that ideally what you most need there first are plants that will send out roots on the surface, since it's always dirt on the surface that gets washed down the hill first when it rains. That's easier said than done, though, unless you have the capability of watering through a drought whatever surface-rooted plants get planted there. But a lower area of azaleas, rhododendrons, camellias, and kalmias would be beautiful, if you might have a little bit of shade to make that work.

Assuming that it will take a long time for whatever plants you select to put there to hold the dirt sufficiently, I'm thinking that if you have available lots of twigs from hardwood trees or nearby woods, you might augment things inititially with heavy doses of twigs, leaves, and mulch, in as long and wide an area as you feel like working on.

Best wishes,
Mary

Why not do some terracing with landscape timbers? I think it would be charming.

Kate

What about groundcover roses?? Heirloom once had a very low growing groundcover rose called 'Green Snake' that intrigued me for the longest time. It was a mass of white. Less than one foot tall but a spread of ten to twelve feet. In fact, it still intrigues me.

You have great ideas. Mary, I totally understand what you wrote, and I intend to try it. We cannot get trucks back there because we have a rose arbor that they cannot get through. So, we have to pull wagons and wheel barrows through to get the dirt.

When I plant a rose, I put in a 40 lb. bag of top soil, and one of compost. I intend to put any clay in that area, then when I plant something, I will add the mixture mentioned above.

I already have 15 roses in that area, but some are on the top. I was going to ask if rose roots will hold the soil, but I should know. I have 3 or 4 Penelopes, and would like to learn how to take cuttings, and plant them. They seem to have rather large roots, but they are old. I am afraid that new roses won't do much good for about 5 or 6 years.

Kate, that is what my husband wants to do. I am reluctant to use the timbers because a few years ago we had a terrible infestation of ants. Even with the house treated for termites, they could infest the timbers, and create a huge mess. We have considered using cement block, though and forming terraces. I just don't know how to hold the soil even with terraces -- except for the good advice you have given me here.

Marcy, I want to look that up. That might hold the top, but I wonder if it will hold the lower soil. I have never heard of that rose.

We also have the ground cover firs, but again I don't know how big the roots are.

Sammy

Sammy, I have always adored the looks of terraces! If I get a vote, I vote for terracing! :)) Terraces especially look good if you can plant some loose weepy things to hang down over the wall edges here and there. I am envisioning a winding path circling down the hill, with a bench near the bottom... :)))

You are so lucky to have a large sloping area now to be planning, and I'll bet it's going to look really good when you get your things done there.

What you use for terracing (if you do terrace) to hold the dirt in ought to take into account the looks of your house and the materials used in the rest of the landscaping in your yard and in the area.

If you end up choosing cement blocks for terracing, you might consider putting a textured surface onto it. There are (or at least used to be) products that you can smear onto a cement block wall to make it look like stucco or other textured surface, or to simply seal it off (to help keep your basement dry with a cement block house foundation, for instance). Some of these products come with coloring built into them, so that you never have to paint the wall (if you don't want the regular grey color with white cement for the joints).

I have also seen pictures of a wall that looks a good bit like smoothed adobe (and might have actually been adobe) topped by red bricks, and it looked spectacular. Cement blocks with a surfacing material applied to them could mimic this look for a lower cost.

I could be wrong, but I don't think termites go after landscape timbers that have been treated. I know for sure that there are termites around here, but we so far haven't had them working on our landscape timbers that lie directly on the ground. We use the 6" x 6" kind and like their looks a good bit. They are becoming increasingly heavy for my husband to manage, though; buying the shorter lengths to get the job done might be worth the extra cost.

You can also have a beautiful, beautiful bank without going the terrace route, of course. I'll include a link to one such gorgeous sloping garden. It comes from Carolyn Parker's website.

If you end up looking for some roses to use as ground covers, a couple that I've seen people praise are Alberic Barbier and Blushing Lucy. I haven't seen Renae used that way, but I'm planning to try using Renae as a ground cover here. That one is fragrant, nearly thornless, and likes to bloom a lot if she gets a reasonable amount of sun.

Sunset Magazine has some books out that you might enjoy as you think about what you want to see on your slope. Two books you might want to look into that I just found at Amazon: "Sunset Hillside Landscaping" by Susan Lang, and "Hillside Landscaping: A Complete Guide to Successful Gardens on Sloping Ground" by the Editors of Sunset Books. We don't have these particular books, but the other Sunset landscaping and gardening books we do have are very, very practically oriented for building things and have been well-used around here.

A slope is so much more interesting than a flat surface! If your yard were all flat, ideally you'd be trying to create some slopes, wouldn't you? It's wonderful what you have to work with now! Best of luck with it!

Mary

Here is a link that might be useful: Red Rose Ridge, a garden on a slope

I always love seeing Pam & Michael's roses. It is a beautiful garden indeed.

They are contemplating doing the same to our creek--er--digo--drainage ditch. They cleared the creek bed a block downhill from us and planted a bunch of grass and put in some huge ugly concrete blocks.

1. All of the deer & other varmits moved into "my" back yard. Goodbye tomatoes to say nothing of the roses!
2. I hope that the grass they planted does not have to be burned every three years or so.
3. I hope they did not put in an ugly access road along your ditch!

A good friend retired this last year and signed up for the gardening duties for his church. He was rather upset that he could not get a fire permit to burn the native grasses that someone had planted many years ago. The church was in the city limits. He said it was not any fun digging up the native grasses with their deep roots.

Granted it would be nice to get rid of our mulberry tree, but the trees add a certain charm to our valley. Where would the Mallard ducks live? What about the groundhogs, the wrabbits, and the posums?

On second thought; bring on the bulldozers!

Sorry about your loss. I feel your pain.

I am sure you can find some nice trees like Cleveland Pear, Willow, or Mulberry etc.

Here is a link that might be useful: Nine sacred trees

I don't know if they work where you live, but I have had good luck with daylilies. They eventually spread to choke out anything else (with the exception of the occasional bindweed) and they have held the slope below my driveway for years. Plus you get to dig up and divide every few years - or not; there are plenty of old farms around here with a thick choking border of old fashioned orange ones that have been ignored for decades.
I don't use the orange ones much - there are so many interesting pastels. I am partial to Lime Frost, which looks great with pinks and mauves.
I don't water, after the initial few weeks after planting, because I have a well, and the roses get first shot at water, after me and the laundry.

There are such great ideas here that I thought I would revive this thread.

We have lost more dirt than I thought we would while I have been thinking.

I need to refer back to these posts, and thought you might also enjoy reading them. Feel free to add anything.

Sammy

If the slope is unstable plants will just go down it along with the dirt. As mentioned, a slipping slope needs to be tamed with some kind of engineering solution before planting is attempted. If you don't own it you may not want to put enough into it to firm it up adequately. Talking to whoever is in charge of this patch of ground would probably be a good idea.

Part of my family lives in the place with continental dunes, so they have to maintain their hillsides, otherwise whole hill would move a few miles further. What they do is some sort of terracing, basically you put in low stakes in the ground, every 1-2 feet from each other and then twine left over branches from pruning in between of them. I don't have a picture of their terraces, but here is some from the Baltic seaside, that's how they prepare beach for the storms, so sea does not wash out sand of the dunes.

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Good plants for this sort of situation are all sorts of mountain pines (those grow quite low and have deep roots), iris tends to develop huge root system, daylilies, hydrangea arborescens, rudbekias, thistles, sea holies, peony (both tree and normal ones), cottoneasters are good also, since they can crawl the slope and root in along the way, honeysuckle can do the same, if grown not as a climber, but as ground cover, also ferns are good if there is some shade.

i would second pines such as pinus mugo, pinus koreana. Also phlox - stolonifera, subulata. saxifrages can be good, shrubby honeysuckles, roses such as macrantha, R.sancta, R.paulii, acanthus (although it can be a thug) herbaceous clems (integrifolia such as arabella, durandii) bidens, grasses such as elymus magellanicus, deschampsia, molinia, various stipas, heleniums,alstroemeria. Have a look at alpine plants such as pulsatilla (if you have an alkali soil), rock jasmines (androsace) aubrieta, campanulas (many creeping types such as portenschlagiana, pulla, barbata, sarmatica, cochlearifolia), helianthemums, some of the ground cover roses such as Grouse or nozomi, a lovely tiny sorbus reducta, symphoricarpos (can also be a brute though).
If you do go for some sort of retaining wall, the cheapest method is to use rendered cement blocks sitting on a generous footing, capped with timber or sideturned bricks or slabs Or you can simply render the tops too, especially if you use PVA in the render mix.

i would second pines such as pinus mugo, pinus koreana. Also phlox - stolonifera, subulata. saxifrages can be good, shrubby honeysuckles, roses such as macrantha, R.sancta, R.paulii, acanthus (although it can be a thug) herbaceous clems (integrifolia such as arabella, durandii) bidens, grasses such as elymus magellanicus, deschampsia, molinia, various stipas, heleniums,alstroemeria. Have a look at alpine plants such as pulsatilla (if you have an alkali soil), rock jasmines (androsace) aubrieta, campanulas (many creeping types such as portenschlagiana, pulla, barbata, sarmatica, cochlearifolia), helianthemums, some of the ground cover roses such as Grouse or nozomi, a lovely tiny sorbus reducta, symphoricarpos (can also be a brute though).
If you do go for some sort of retaining wall, the cheapest method is to use rendered cement blocks sitting on a generous footing, capped with timber or sideturned bricks or slabs Or you can simply render the tops too, especially if you use PVA in the render mix.

Landscape Timbers aren't what they used to be. DH has used them a lot and the da##ed things are rotting in five to six years- even the ones that are up in the air- the ones that should be drained dry first. Then I read the little plastic tag on the end- it doesn't guarantee any longevity at all.

Re daylilies: they don't call the ones gone wild ditch lilies for nothing. We have one very steep slope and they and periwinkle keep it stable.

R. sancta seems happy to spread in the worst dry red acidic clay on our property; so so the spinosissimas (except for the rebloomer that sulks). Also the spreader R. wichurana spreads wonderfully.
Spreading deeper is Alika, the gallica- vibrant red orange blooms, it's my longest blooming gallica.

And (God help me) for the really uncontrollable, Creeping Charlie can hold a slope (and looks deceptively good from a distance.) (But it's only for isolated places that you never intend to reclaim.)

LIRIOPE comes to mind...the stuff has the thickest, strongest grass-like turf imaginable. My DH spent one whole day digging out a bed of it for me where it threatened to extinguish all the other lifeforms that were planted in it.

We dumped it in the compost pile in the back meadow, and I noticed the other day it is STILL alive and now blooming happily...even though it was dug up one month ago and hasn't rained since and the temps have been brutal.

ann,
you are so right re.timber. These days, timber is barely seasoned at all before being tanalised - weeks or months then they get stuffed in drying kilns instead of being stacked and turned for a couple of years at least. - not only do they rot, they twist and deform because they are still practically growing!

Agree with those who suggested terracing. Also agree that ornamental grasses and Crapes would probably end up shading the roses (since I've had it happen). If you simply want a groundcover to suppress weeds and hold the soil, might I suggest Buffalograss (especially since you live in OK)? Drought resistant, deep rooted, builds the soil if you mulch the clippings. Only probably is that it needs a little maintainence to keep it thick and it may occasionally need mowing.

ProfessorRoush (www.kansasgardenmusings.blogspot.com)

I have moved this subject to Hillside photos and slope.

Elemire, that is fascinating. After the storm does the barrier wash out in time, or do you leave it there permanently?

I appreciate all of your responses. I live in Tulsa, OK, where our summer heat is way too hot. Thank you for your suggestions, and the pictures are on the other post.

Sammy

Sammy, normally they leave it there permanently, because the dunes are suffering the erosion. However, it gets pretty much covered by the sand and generally looks like some sort of decorative fencing.

With the soil, the branches decay eventually, providing the organic material and they do not get infested by ants and other bugs that much. You can renew it later of course, but by the time it decays, plants usually can hold the whole hillside already.

I'm grateful for the search function that actually worked this time. Lots of good ideas for my problem. Hope no one minds my hijacking with a variation on the problem.

This long and narrow woodland garden is along the main path to the back garden. It is prime real estate, so its appearance is important. It has about a 30% slope in some spots, less in others. Over the years soil improvement and organic mulch has raised the soil level above the bottom retaining border of cobblestones. Also we've gotten rid of a number maples and the soil has fewer roots to hold it.It is thickly planted with spring and summer perennials, but in early spring when heavy rains come there's no foliage to help retain the soil.
This really is a display garden, and there aren't any agressive plants for erosion control. And this early in the spring there no foliage yet to help hold soil.

When I heard the forecast for heavy rains tomorrow I remembered last year that my beautiful top dressing of compost washed away. Tonight you would have laughed to see my husband and me gathering rocks in the dark. I quickly constructed a half dozen small terraces around my most vulnerable plants and to hold the soil on the steepest area. I reiforced the cobbles with a taller line of stones.

My little stopgap retaining wall of rocks along the cobble edge looks really silly. I want something less obtrusive. It really only needs to be an edge 2.5-3 inches above the cobbles.

I think another row of cobbles on top would look massive, and would be unsteady unless mortared.

I wondered about wood shingles on edge, held by ...what?
If I stained and polyurethaned them they should last awhile even in soilWhat do architectual shingles used on roofs look like up close? That should last 20 years.

I loved the look of the twiggy fence, though it is hard to imagine weaving branches on something only a few inches high
I suppose I could just make thick twig barrier backed with leaves.I just thought of short willow edging, but I know that has a very short life.

I'm interested in more of your creative solutions. Fire away!
Thanks so much,
idabean

Sammy,

Would you be opposed to using landscape plastic? On my hill I have the thick plastic (not landscape fabric) running from right to left. I started at the top and each piece added (below the one above) is overlapped by 4 inches.

What happens is..well first, GREAT weed control...but also, a good bit of the water on the hill sheets off on top of the plastic. A large amount also runs under the plastic because of the overlap. I have discovered that my plants NEVER need to be watered in the summer (saying a lot for SC here) because the plastic traps in the moisture for long periods of time. I use pine straw for mulch but leaves would work too. My hill is not too steep that this is slippery.

My erosion is pretty much under control. The water that runs on and over my dirt is diminished by half...and that was enough to curtail the soil run-off. I have used daylillies where I thought I might still have a problem and they work great.

This is an older picture but the best to show the slope of the hill:

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Ronda

With all the slopes in my garden, the most important thing has been pathways that make the slopes accessible for maintenance. Blocks of stone I can walk on that are securely in the slope so I can step on them confidently. If you can't walk easily, you can't maintain it. Even if it is only once or twice a year you need to get up there, a stable, safe way to walk on the slope is really, really helpful.

It is so interesting to read after a year what you have written.

I decided to maintain roses at the top of my hill, and crape myrtles on the slope. I have not decided exactly what else to put in, but not roses.

I cleard out all the older roses, and now have 3 entrances. I have a bed of 3 Souvenir de la Malmaison, under that Bubble Bath then Duchesse de Brabant.

In the middle I have Madame Antoine Marie and Lady Pamela Carol and under them Star of the Republic.

On the other end I have FJ Lindheimer and G Nabonnand, under them is Penelope (the only rose left in the hillside.)

On the far end before SDLM I Have 2 Cramoisi Superieur, and another Duchesse de Brabant. I also have Monsieur Tillier if it lives.

In the hillside I will have some steps and three crape myrtles.

Ronda, did you bring in dirt to put over the plastic? We have no truck access to our slope. The city did, but theirs was for flood control. My slope is about like yours, but our access is at the top. At the bottom we have a level area that will fill with water at times, then it goes down to a creek.

I appreciate this thread appearing again, and I wanted to respond and thank you for posting. I agree about being sure footed, and making the area safe.

Since I still work full time, this is a terribly busy time for me. I purchased some Stela de "oro" lilies, but have not planted them yet. I like the bushes you have in your picture. I ended up having to fight poison ivy before I took out my large unruly roses.

Sammy

Sammy,

Pine needles and leaves are all my hillside gets on top of the plastic. I replenish this annually where it is thin.

I don't have many mature trees in my neighborhood so I will use pine needles until our trees mature.

HTH