Look into sedums, especially reflexum and oreganum. They are very drought tolerant and easy to maintain. They won't choke out everything, but they will help.

There are also some nice dense varieties of creeping thyme and wooly thyme that will make a dense enough cover after a year or so that most weed seeds won't hit the dirt.

Moss phlox might work, but mine is being a bit tempermental.

I am also experimenting with a low-growing euonymus called Kew Winter Creeper. I think it likes more shade, though.

How many to get depends on your budget and how long you are willing to wait for them to grow together. If you plant any of the plants above about a foot apart, they will probably achieve a 100% cover in two years. If you go down to eight inches, you can probably see nearly complete cover in a year.

I would probably draw two lines down the 15"-wide strip, each five inches from the edge, then stagger the plants at eight inch intervals (approximately... vary it a bit if you don't want it to look too regimented). Within a year or so, you will have conquered the strip!

If you haven't already been there, you might also want to ask the same question on the groundcovers forum.

Pianojuggler,

THANK YOU so much for all the information. These are the exactly what I wanted to know!!

I checked out all the pictures of plants you recommended, I really like wooly/creeping thyme the best.

Now, I'm wondering where I can get the grower flats of them in Seattle... If I can, I would like to plant them sooner than waiting for spring due to our rainy winter (I believe the rain will help them established better before the next drought, correct?).

I'll also look into groundcover forum.

Thanks again!
-b

A relatively narrow 60' length with only a single planting of a very low, ground-hugging groundcover may be a bit more boring than you expect :-) While creeping or woolly thyme are very nice and pretty rapidly spreading GC's, they are rather characterless when not in bloom (and not nearly as great a weed deterrent as a few other GC's). They offer a much better aesthetic if grown on a gradual slope or even on low, rolling mounds. I'd consider adding some hefty landscape boulders to create some contours (and take up some space - you have a lot of real estate to cover) or selecting something with a bit more oomph to it - Rubus calcynoides or Genista pillosa 'Vancouver Gold'. Both will grow and cover far faster than the thyme, have more of a profile and offer much better weed suppression. The Euonymus fortunei 'Kewensis' PJ mentions is also an excellent choice and tolerates sun very well.

Growers flats of GC's have become increasingly difficult to locate in recent years and even my best GC suppliers offer them only in the summer months and infrequently and very selectively at that. But with a very low growing, mat-like GC like the creeping thymes, you can easily cut up the typical 3.5" pot into 4 or more chunks, thus increasing your supply. I'd also recommend holding off on the planting of thyme - if that is your choice - until spring or after the worst of the rainy winter. Unless well-established and in extremely well draining soil, it dislikes the amount of moisture we receive in winter.

For a 12" spacing (and no boulders) you need 900 plugs/pots - for an 8" spacing, you need approximately double that. With either the rubus or genista, you can easily get away with 16-18" spacing or 400-600 plugs/pots.

Dang, I hit that "send" button faster than I meant to :-)

Another plant that I find more suited to this type of mass planting are Heliantheums or sunroses. Fast spreading, drought tolerant, sun-loving evergreen spreaders with a startlingly beautiful and long lasting flower display.

Finally, have you considered more of a mixed planting for this area? A few of those boulders carefully arranged will make an excellent foil for a few selected dwarf conifers and/or small evergreen shrubs. Add some ornamental grasses and groundcovers of your choice - with this type of planting design, you can select more than a single type of GC (doesn't work so well with a mass planting) - and you're good to go for a low maintenance, drought tolerant and very visually interesting planting strip.

Hey, I'm boring. What can I say? I have a section that's 10' x 40' of just wooly thyme. And I'm planning more.

But Gardengal is right... some boulders or other stuff might spice up the strip. Sections of WT as a foundation, and other plants to break up the monotony wouldn't be bad. Maybe a couple junipers or heather?

Anything but ivy.

-pj

gardengal,

Thank you so much for your input. I like the look of "Rubus calycinoides" and sunroses. It's great idea to mix some plants up. Do you think I should get sunroses in pots rather than seed?? If it's high enough success rate to start from seed, I would like to try it.

Btw, what all you think about using evergreen/semi-evergreen herbs for groundcover??

So far, my oregano, sage and italian parsly are mostly staying green during winter. Especially parsly were so easy to start from direct seeding outdoor. Just curious to hear your opinion about these herbs..

Thanks!!
-b