I forgot to add Alliums. Anybody grow those?

How much room the plant is going to take up is going to depend on the size of the plant. Saying they will take up 2.25 sq ft is assuming they are going to be 1.5 ft across. Maybe and maybe not. Given the size of the bed, this pretty much translates to a strip of perennials around the edge.

Alliums behave like most spring bulbs. The dying foliage can be a bit annoying.

For drifts of color at the feet of roses I like the lower growing Nepetas. Little Titch is a good one. They bloom all summer, bees love them, and the blue/grey haze they create is a nice contrast to the roses. They will spill over your wall quite nicely.

Cranesbill "Rozanne" blooms from spring until frost. It would trail over the edge of the wall if you want it too, mine grows up into the roses. If it gets too leggy, you can cut it back and it puts out new growth and keeps blooming. Homestead Verbena is a good plant for spreading(it really, really spreads) at the feet of roses and draping over a wall. I use all types of salvia and foxgloves. Oddly, my foxgloves bloomed all summer and I still have some blooms. I cut the stalks back after they finished blooming and they put up new stalks and bloomed again :-) I can't keep lavender alive here to save my life.

Carol

Debbie, you're going to have fun. Lavender doesn't like a lot of fuss, they're used to that Mediterranean sand and heat, almost thrive on neglect. I love them with roses.
You could do a couple daylilys.

Carla

Off the top of my head, I say you are going to need erosion control on that sunny steep spot. I would put sedum in right away. You have lots of choices there. Good luck.

Barbara

MadGallica - that is a good point, most perennials will take up about 1.5 feet eventually. Maybe I could move the roses back 6-12 inches, they will just have that back liriope at their feet.

Lindyb, I do like that nepeta. I have not tried it before but it would definitely be the right height and color.

Carol, if you can't grow lavender, I doubt I could. Do they prefer dry conditions? I do have Rozanne elsewhere, and you are right about the blooming time. I will look up the homestead verbena.

Carla, when you say mediterranean sand, do they prefer sandy soil?

Barbara, are there any other choices for erosion control besides the sedum?

Thanks!

Redsox, I'm dumb about companion plants, but I have had success with Spanish Lavender planted in total (builder's) sand - that way it drains well. It's supposed to be the only Lavender that does well in wet, humid Florida. I have even had success with Rosemary in sand. My problem here with companions is that they quickly become huge - bigger than my young roses. You probably will have nice petite plants that look wonderful. I also wouldn't go any closer to that Liriope than I had to. I found them to be a real barrier to the roots of roses I had planted near them. I finally moved the Liriope.

If you don't mind an unrelated thought, I think I would add more stones to raise the height of the wall at the low end. That would reduce the slope and the run-off and would give your last rose more level ground to settle into.

When are you going to plant? Can't wait to see more photos. Have fun with your planning!

Sherry

Debbie, from everything I've read, lavender likes a more arid climate (less humidity), dry feet and lean, well draining soil. I have humidity galore, clay soil amended with tons of manure, and the water requirements of the roses may be too much water for the lavender. I just know that I've managed to kill quite a few plants! Perhaps I tried the wrong varieties but I can get the same effect with other plants (sadly, not the fragrance) so I quit trying to grow it here. I do love the smell of lavender and it may do well for you in your garden. Give it a go. Try the kind that Sherry mentioned, if it thrives in Florida it should do fine in your garden. As always, you won't know how it will do in your garden until you try it for yourself. You can dig it up and plant something else if it doesn't work out :-).

Carol

Dianthus would spill nicely over your wall. I second the vote for short nepeta, it really does bloom all season and it attracts butterflies. Homestead purple verbena was a thug in coastal NC (It went crazy after getting a taste of Rosetone) but it probably isn't perennial for you, replanting every year would keep it small.It does bloom continuously and attracts butterflies. I have tried a couple of salvias and thought the foliage smelled yucky, YMMV (you'll look silly sniff testing salvia at the local nursery. Sorry).

What lavender wants, and has a hard time getting on the east coast is lime. So I can grow it in heavy clay. The lavender didn't even mind The Year It Rained, unlike the balloonflower which rotted.

I do have to stick to the hardier varieties - Hidcote, Munstead and Lady. It makes better shaped plants the more sun it gets, and it's important to prune it back in the spring after it starts growing. It's not a difficult plant at all.

Anything with roots can control erosion. The more, and more fibrous roots a plant has, the better it is at erosion control. So from my experience, the plant I'd put there is catmint.

Making the bed wider isn't an option? I have no idea how big those roses are going to get for you, but when I originally laid out what was planned as an HT bed, it was 4 ft, and HTs tend to be quite small here, and extremely narrow.

Debbie, when I planted my lavender I added play sand to the holes. I don't water them except when they are new. They get whatever rain provides or soak up what the roses are getting. Some of mine are on a hill and some are not. They don't like too much moisture or other amendments I know that.
I agree with what Barbara said too.

Carla

Erosion Control: Choices? Yes! Tons! I suggested sedum because it is also drought tolerant, virtually indestructible and easy to propagate. You can use most any plant that will take hold quickly and spread. On my slope I have sedum, daylilies, black eyed susans, prostrate juniper, moss phlox, coreopsis, berberry, globe arborvitae, lambs ear. The list is quite long. Campanula carpacta and siberian iris would work in the shadier areas. Nepata or Salvia would also look nice. A relatively new ground cover called Microbiota desscusata or Russian Arborvitae is supposed to be a great sun or shade evergreen ground cover. I'm planning on trying it next spring.

I agree that your bed is too narrow for roses AND perennials.

Barbara

Hmmm. Based on the choices and information I think I might try the nepeta. But if the bed is too narrow....I will have to think about digging out the liriope in the back.

mad gallica, thanks for the info about Lavender. My soil is limey so that must be why it's doing well. Does lavender work in the shade? I have some dry, limey shade that needs plants that like it.

Sorry for the hijack, redsox.

Sherry

Kay, believe it or not, I just recently, "finally", sent my soil to be tested. Everything is growing well here, except for lavender, but it will be interesting to know if I am "acid" or "alkaline" for certain and to see if I need to add anything to the soil this fall. I wasn't having any particular problem, just wanted to know :-)

Debbie, some of the nepata grows much taller than others, so make sure you get a variety that will be the size that you want in that bed. I have nepata growing near Belinda's Dream, I think it is Walker's Low, and it has to be cut back ever so often to keep it from overtaking her. It grew a bit larger than the stated mature size. It doesn't seem to mind a trim, though. I would dig out more of that liriope and give the roses a little more room!

Carol