Dart's Dash is a good one.

The good part:
a hedge of rugosas in bloom is something that makes people stop and take pictures, it is amazing.
Rugosas are very hardy and very healthy. There are some hybrids which are NOT healthy so a bit of care is needed (just ask in case of doubt).

The bad part:
However, the problem is the size you want. As far as I know, no rugosa is smaller than 4-5 feet and they tend to grow larger in colder areas. The so-called dwarf, roadrunner, minis etc easily grow to 6 feet or more!!
If you are thinking "ok, they'll grwo larger, I will just prune them with a motorsaw", NO: rugosas do not like to be pruned, and YOU will not like it, as there is nothing as thorny as a rugosas, cruel asymmetrical thorns of different sizes and shapes...

Some hope, after all:
You could try dagmar haartrup: I have 3 of them and they are all 3-4 feet tall after 3 years, never pruned, but I think that in a cold zone they might grow bigger...

Where in Washington state is it zone 3/4?
My experience is Rugosas stay shorter in colder zones and some may require a little tip pruning in spring. I provide no winter protection for my rugosas. Marie Bugnet is hardy to zone 2 and stays about 4 feet for me. Snow Pavement is hardy to zone 3 and gets about 3 feet.
The following stay four feet or less for me.
Pristine, Scarlet, and White Pavements are hardy to zone 6 but grow nicely in my zone 5 with just a little tip damage. Foxy (Buffalo Gal), Pink, and Showy are hardy to zone 3.
Dwarf Pavement grows 3-4 feet and is hardy to zone 3.

I grow all of the above so the heights are from my experience.
Rugosas are some of the first to show leaf buds in spring but one shouldn't worry if a cane or bush seems to be slow leafing out. About the time I think one or two bushes is in trouble, I see new growth.
The pavement series were hybridized to grow in the center strips of highways and along the side of roads, so they do well with minimal care and no winter protection.

Karl,

Technically, I am in zone 4, since it gets -27 F. many winters. I am in Eastern Washington, five miles from the Idaho border. We have a creek behind our house and we're in a small valley, so it gets much colder in our area than most of the surrounding area. The reason I started putting zone 3/4 is that some plants are listed zone 4, but only go down to -20 F. This is especially common with fruit trees, but I've also seen it on some of the old-fashioned roses. I guess the idea is that if they're cold hardy to -20 F, then they're zone 4. I would think down to -30 F. would be zone 4, but maybe I'm wrong. Away from the house, with the wind, I would guess it's at least that cold. The confusing thing is, according to my zip code, I should be in zone 6 :) I've lost too many plants that were zone 5 (and planted up against the house, in a protected area) to believe that.

Therese Bugnet is really pretty (there were pictures on the Antique Rose forum). Is Marie Bugnet white? Those would be pretty together. I've heard they get taller in the south, but Northland Rosarium (outside of Spokane, WA) says that Therese Bugnet stays about four feet here. I've heard Therese Bugnet doesn't have many hips, but I could make up for that elsewhere.

I'm also planning to add four roses in the herb garden next year. After talking to the people on the Herb forum, it sounds like Fru Dagmar Hastrup would be a good choice and has a lot of hips.

Thanks for the input and what do you think of Therese Bugnet and Marie Bugnet planted together?

Lavender, I can confirm you 100% that Dagmar Hastrup is one of the most generous hip-setting rugosas. Even more than foxy, and matched only by scabrosa (which is however very much larger and taller!). I have 3 DH and they are between 3 and 4 feet tall and large.

Karl, thank you for telling me the size of your rugosas. I have all those you mentioned (except Marie Bugnet), but here in Z8a the foxy-dwarf-pierette etc are now 5 feet and keep growing (and blooming and setting hips).

Therese ugnet is a very nice rose, but no hips. Very decorative purple canes in winter, anyway. Mine grow in the wind, in a shady area, poor soil, and is nonetheless ofer 6 feet tall and 4 large. Wonderful healthy monster.

I don't grow any of these, but I'm quoting from Lois Hole's Rose Book. I won't mention those that others have already mentioned.

1. Frau Dagmar Hartopp
FDH is an impressive rose, with silky-petalled, silvery-pink flowers that shimmer in sunlight. These highly perfumed, poppy-like flowers are large, from 3 to 3 1/2 inches across and cupped like a wine glass around creamy yellow stames. Blooms until fall frost, with the greatest profusion of flowers in early and late summer. It has large red rosehips, which look like cherry tomatoes, and glossy foliage which changes from green to purple-red to deep golden-yellow brushed with copper. Does well even in shade for half the day. Thorny. Highly resistant to BS and PM. Height 2-3tall 4-5 spread. Scent strong, clove-like. ARS rating 8.5

2. Red Frau Dagmar Hartopp - deep magenta. 3 feet up X 4-5 feet spread. Single flowers. Very showy rose. This rose makes a wonderful hedge, because its thorny branches create a formidable barrier. Blooms until stopped by fall frosts with cupped 3 to 3 1/2 inch flowers. It produces abundant cherry tomato-like rosehips and is one of the best roses for fall colour. Does well in shade for half day. Very vigorous and highly resistant to BS and PM

3. Schneezwerg or Snowdwarf - Disease-free, glossy foliage that turns bright orange and yellow in fall; sweetly scented flowers all summer; extreme cold-hardiness; and the ability to thrive for years and years under almost any conditions. Bright white, 3 inch flowers have pale yellow stamen and are borne in clusters of 3 to 10. Tolerant of shade and poor soil and makes a superb hedge. 3-4 spread. Semi-double This variety is one of the showiest roses in fall, with colourful leaves and abundant orange-red hips, often produced while the plant is still flowering.

Carol :)