Sammy, This is a significant problem for us as well, as we have steep ground and deep clay: our various slides revealed five feet of clay at least, and no rock yet at the bottom. I don't have any tried and true solutions, but can at least share what we're trying. Maybe some of it will be useful. I've gotten really cautious about disturbing the soil by plowing or earth moving: if it's more than can be shifted by a shovel or a hoe, we leave it alone. All our slides have been in areas in which the soil had been disturbed. And more and more I'm leaving herbaceous plants--weeds and grass--until I have something to put in their place, since, as Elemire pointed out, the ground benefits by the holding power of their roots, as well as by the organic matter they add. (However I totally agree that the poison ivy has to go.) We do a lot of minor terracing (to a height of about a foot in the garden) with boards and rebar, which are very plain indeed but work to define beds and paths, and make the former field look much more like a garden by giving it flat areas. I would use rocks for terracing if we had any. And we have deep-rooted trees scattered through the garden, hoping that they'll be well enough established in a few years to prevent slides, as so far seems to be the case. In the case of ground that requires restoration, particularly in the case of the slide areas that have lost their topsoil, I leave all herbaceous growth (that means weeds) of course, and intend to plant native colonizing shrubs. We've planted seedling trees with minimal success, so I think we need to back up to colonizing plants. The heavy mulch we keep on the ground slows down runoff and allows absorption of rain; at least I think it does. All of these strategies are thoughtful, but we have no training in soil conservation or related topics. I'm returning to Italy next week and will be able to see what my garden looks like after a month and a half here in Florida. My husband tells me that we got two inches of rain last week, which is excellent for August, and makes me hope that we might enjoy a decent fall flowering this year, the first in some years. Florida has been really hot and humid this year, so much so that I've hardly gone outside except to go swimming; and if I had a garden here I can guarantee you I wouldn't have been out working in it. This week the heat has finally eased up a little. In a climate where summers are hot and dry by this time gardens often look really ratty, young gardens especially. Yours looks like you're off to a good start: the roses look robust and healthy. I know that when I pass the summer in Italy I dedicate my garden time to pulling bindweed and Bermuda grass and it's no fun at all, but fall is on the way. I think that when our trees and shrubs get some size on them the whole garden is going to look a lot better, and will be more comfortable with the shade. These things just take time, as I keep telling myself. ...

Update (2013 follow-up) of successful steep slope plantings on a dry sandy slope in So. Calif. In my previous post, I listed drought-tolerant Calif. natives used in my initial plantings. But the fire department does NOT like summer-deciduous plants such as sages. And as water was reduced, plants such as Wooly Blue Curls did not survive. It has been a 10-year project and this is how I turned a steep dry sandy slope into a drought-tolerant garden: 1) Basic Calif-native trees & shrubs were planted (a couple of Coast Live Oaks, lots of fire-resistant Toyons, McMinn Manzanitas, Sunset Manzanitas and the wonderful Hollyleaf Cherry are good choices). At the driest upper areas, Palo Verde Trees were planted for their deep tap roots and provide 25% shade cover when leafed out during the summer. 2) The slope is very steep. As I worked the sloped while planting and watering, a curvy informal foot trail started to form. As the trees and shrubs took hold of the soil, these foot trails were gradually deepened. Most native ground covers are sold as tiny little things that can't get a hold on steep slopes or are buried under a shovel of dirt unless planted at the base of an agave for protection. Tip: Buckwheat prostrate is a great steep-slope ground-cover that drapes down and hides the vertical cut edge of pathways. 3) The native flower shrubs (Wooly Blue Curls) died. Calif. Fushia is very dought resistant and is best if tucked under an agave to brighten up the driest desert plantings at the upper level. As the trees, shrubs and trails became established, lots of agaves were added to hold the surface soil. Cabbage-sized boulders were often used to hold new plants into the slope. 4) Erosion: A line of three monster Blue Agaves were planted in a horizontal line whenever a "dam" was needed to divert rainwater from running straight down the slope. The maturing slope contours (trails) were gradually deepened and dirt bermed up so that rainwater would travel across the slope and flow into collection basins behind trees and shrubs along the way. The pathway/contours took a lot of time to evolve but was well worth the effort. Instead of walking "on" the slope, the deepened pathways amongst the plantings now gives the feeling of a nature hike. 5) Gradually, non-native plants (aloes) were added to the semi-shaded areas. For the upper "desert" area, tons of barrel cactus and agaves were used as a ground cover alongside uprights such as pony-tail palms and colorful upright non-native Sticks on Fire & Crown of Thorns. This large (1/2 acre) hot dry, sandy steep slope was a real challenge and still is not finished. To make things look right on a large steep slope, you will need dozens of each plant to form groupings. You can use dozens of spikey Agave Geminiflora to give the illusion of a "meadow". Dozens of Golden Barrel cactus planted in an informal "swirl" along a switchback gives the impression of a flower garden from a distance. With a little imagination and a lot work, a steep slope can become a beautiful garden. Take courage, though, because it takes YEARS before others are able to "see" what you have planted. And on difficult slopes, it is better to overplant your basics of trees & shrubs because on a contoured steep slope, a sprinkler grid is too complex and you will lose some trees/shrubs when hand-watering is reduced.

Those wildflowers at the top of the slope look like mallows of some kind, maybe Lavatera. I like your palm tree. Looks like Trachycarpus. Very hardy and has flowers when it's taller. It also drops fronds, but not often. What you put on your bank really depends on how much time you have to stay on top of the care needed for the first year or so until any plantings get established. There have been some lovely suggestions offered already: the iceplant and the local Ceanothus. There are varieties that spread beautifully to smother. Otheres are taller and more bushy. They come in a small range of colours, mostly blues and purples and they can provide a succession of flowers over weeks. I liked the idea of the California poppies. They are so tough! And there are colours other than the standard 'orange'. You might want to plant 'pools' of them among Ceanothus to give a fairly strong visual impact. A 'Pacific' colour scheme suitable for strong sunlight. Pastels tend to get a bit lost in hard light. The iceplants can be very effective - big sheets of colour usually in 'hot' tones, although there are softer pinks available. And, for seriously tough sites - Gazania, Arctotis, Anigozanthis (kangaroo paw - which comes in a pleasant range of flower colours dark red to interesting green.) They're usually perennial. Climbers and sprawlers - Bougainvillea, Campsis, Trachelospermum (which smells delightful). Instead of climbing a trellis they can sprawl down the bank, needing only a trimming with shears to stay civil. Bougainvillea has thorns, however. As do the carpet roses and Rosa 'Nozomi'. That's a fairly steep slope so work across it rather than 'up/down' to reduce the risk of rain damage. Leave strips of grass to catch the run-off and protect your pool from mini-mudslides. At least until your plantings are spreading out. Before planting ANYTHING - check with your local garden centre to see if it's safe for newbies. Some things look so innocent when you see them as a cute little cutting in a teeny pot... and then you find they have rule-the-world tendencies. English ivy would be one. Cortaderia would be another. Many South African bulbs, such as Watsonia, can happily fill acres. So can Ornithogalum. And, if it's not too hot where you are, asparagus fern and ginger plant can take over in no time. If you should chance to like them - and don't mind some spiny-ness consider bromeliads. There are many hardy varieties that happily live outdoors, flower fairly regularly and make a good groundcover. And aren't fussy.

We have a steeply sloped backyard too. It is south/southwest facing, gets a lot of hot sun during the summer. Most of it is planted in junipers except for an empty patch that is really an eye sore. We had more junipers planted in that spot because we just can't get down there to trim or weed unless we tied ourselves up to a post and propelled down. There is a zigzag pathway down our hill but the owner/builder really should have added an extra 'zag', because it's really steep. My dream would be to tear everything out, put in retaining walls, a seating area at each turn, a fountain or two too, and for my husband...a zip line all the way down! He's crazy. Because at the bottom of the hill a creek runs along our property and it's just breathtaking! In fact, before we even walked in the house we took one look at the back yard, as steeply sloped as it was, and we knew we couldn't pass this property up. Our slope looking up. Our slope looking down. We've cleared the area by the birch tree and along the creek in the first pic, but on the hill there is still planting to do. Not only that, but the old rail ties that were used are rotting. It may not look like it, but there is a lot of work to do yet. These pics were taken in spring before we moved in, so the hillside looks pretty good only because the weeds in the middle of the hillside are green!