Need help finding a low perennial border plant

I'm landscaping off three 13ft. dia. circular designs in my front yard and would like to border all three with a same low-growing (6 or so inches in height - something easily stepped over to enter the gardens) green perennial. I've fallen in love with dwarf boxwood, but it's not hardy in this zone (Zone 4, by the way........ dead-center of Wisconsin).
Would like to stay away from something flowering, 'tho if I can't, something with small flowers that won't distract from the circles' design themes.
Any help anyone can give would be MUCH appreciated!!
By the way, I'm on kind of a limited budget.....
Thanks!
Kate in WI :-)

Are heucheras hardy in zone 4? The more subtle colors would work, and if heucheras won't work 'heucherellas' heucheras crossed with tiarellas which seem to do well in cooler areas. Or tiarellas themselves. These are all saxifrages, and are sometiems called coral bells, or foam flowers and some of them aren't grown for the flowers at all (see the dark bronze coral bells like 'Purple Palace'. The flowers are only part of the story in some of them, a brief thing that happens only part of the the year, and won't really distract from what's planted in the circle. Plus, as a low mounding plant, they're not going to get so tall you can't step over them.

Google image heucherellas and tiarellas to get an idea of what there is to choose from. youll see some are plain and green and some scream for attention.

Melis

Some heucheras are hardy in Z4 but I have not had much luck with them, I am pretty close to Z3 though. With the price I have to pay for 1 plant it would cost an arm and a leg to put around 3 13' beds. However that would apply to almost any perennial. A plant that spreads is the most economical way to go. I have Ajuga, 'Burgandy Glow' I think, that multiiplies and the babies are easy to remove and could be used to fill in between the more mature plants. Lots of different leaf colors ave available. Only gets to about 2 - 3" in height and flowering does not last long.

Is the area sunny, shady, partly sunny? Hosta would work, although it gets taller than you really wanted. You could start out with less than needed as they can be divided easily tp make more--or get a few large plants to divide yourself and save money. If you divide in the fall, they should look better by spring. A blue fescue could work. I have ovina glauca 'Glauca'. It is a neat mounding grass plant, full sun, 8 inches tall, spread 10 inches, hardy to zone 4, needing full sun. Blue green sedge Cares flacca is also hardy to zone 4, needs part sun/part shade, grows 6 to 12 inches tall with a spread of 12-24 inches. Variegated Japanese sedge Carex oshimenisis'Evergold' is a bright creamy yellow striped foliage with dark green borders. It grows in full sun to part shade, 8-12 inches high with a 12 inch spread,. It likes moist soil and is hardy to zone 4. These three have been successful for me in the Milwaukee area. If you check the garden centers now, they are having sales. You should look for ground covers or grasses if you don't want flowers. My grasses are mostly on the smaller, not larger size. Ajuga could work, but it will grow into your lawn, and you would be pulling it out. Hope this helps. Pat

Clump forming perennials are a good bet.

Like sun Hosta, mums, there are some perennial poppies, corydalis (yellow flowers all summer), dwarf iris, daylilly, dianthus etc.

Visiting public gardens will expand you plant palette and you can ask questions>

http://www.uwgb.edu/biodiversity/arboretum/introduction.htm
http://local.yahoo.com/results?fr=dd-local-more&stx=arboretum&csz=Appleton%2C+WI
http://uwarboretum.org/
http://www.arboretum.umn.edu/gardensandcollections.aspx
http://www.ilovegardens.com/Wisconsin%20Gardens.htm

The nearest is in Appleton, Green Bay has one too.

Some of the shorter bulb plants liks Siberian squill, or tete a tete daffodils (3" tall and short green leaves the rest of the year) maybe even English ivy! Zone 3, that's pretty extreme. I think that's a bit out of my area of experience, really. Most north I've lived is Pittsburgh. I think if I were you, I'd go hang out in the Canadian gardening forum a bit, see if there are any gardeners there with zone 3 experience who could add to the suggestions and rule out some that might not be hardy where you are. Also the propagating forum might be able to suggest some plants you can propagate easily.

Additionally, when it comes to being strapped financially, don't forget that all spring and summer long they have bargain shelves in places like Walmart, Kmart and Lowes, plants that have got roughed up and can no longer be sold for full price that they'll significantly marked down. This year so far I've bought 50+ roses from Kmart for under $5 and about ten heucheras that were originally about $15 which I bought for $1.99 and 3.99. Imagine what that'd all have cost if I'd spent full price for all of that!

Man, I *n e v e r* pay retail!!!

Also, just wanted to tell you, there's a giant bugleweed (ajuga) called Catlin's Giant with subtly different leaves (bronzy veins, dark-dark green inbetween) which might make a really spectacular border for you. I'd think if you can grow regular ajuga, you ought to be able to grow the giant one.

I hope it goes well and you find something you like and can afford!

Melis

Pachysandra will grow anywhere and it spreads, albeit slowly. From full shade to full sun and in zone 4, no problem. Stays about 6 inches tall and has insignificant white flowers early summer. Not at all messy, with a nice medium to dark green color, shaped like little umbrellas. Buy a flat, separate into clumps and plant 2 - 3 together about 8 inches apart and they will eventuallly fill in to make a nice full ground cover. To keep it where you want it to stay, plant inside of landscape edging that goes a few inches beneath the dsurface fo the soil.

Kate, are you there?