My mom grows them and they seem to get most height when in full sun. They require constant watering in the sun then, and the height difference is not that significant. That's all I know.

Martha

Rec'd a large dinnerplate sized clump of The Rocket this spring from another gardener. Divided it into 2 clumps with a third that also separated. The 2 largest ones are blooming right now. One in a rich bed with lots of compost and the other in not so rich amended clay near the downspout.

All are in part shade with less than 2 hours of direct sun. I'm in western WA, so our sun is less intense.

Most of my plants are pass alongs from other gardeners. Perhaps, there is a garden swap near you. If not, you can organize one via Garden Web.

Other part shade bloomers here:

spring bulbs
lilies from bulbs (Asiatic & Oriental)
sweet william
Crocosmia Lucifer
Astilbe
Gold Heart bleeding heart
hostas
masterwort, Astrantia major
Japanese anemone
Siberian iris
Stinking iris, Gladwyn iris
Ajuga, carpet bugle, spreading groundcover, but easy care & nice blue purple spikes

smaller blooms:
London pride saxifraga
strawberry begonia, mother of thousands (might be annual for you)
fumewort, Corydalis lutea profuse, but small yellow tubular blooms with delicate blue green lacy foliage
serbian bellflower, Campanuala
hardy geraniums
lamiums, spotted dead nettle -- recommend only the pink, purple or white bloomers with some white on foliage (Aurea in a mixed hanging basket has attracted hummingbirds just outside my window. A definite keeper there.)
upright fuchsia (bring in to overwinter)

Thanks corrine1. I like such lists. Here is what I already have that you have mentioned:

spring bulbs
sweet william (I thought this was a 'sun' plant...mine is in sun)
Astilbe
Gold Heart bleeding heart
hostas
masterwort, Astrantia major (I planted 6 of these this spring/summer)
Japanese anemone

smaller blooms:

Corydalis lutea profuse, but small yellow tubular blooms with delicate blue green lacy foliage I have 'tons' of these around the garden
hardy geraniums I will have to experiment as to how much shade it can take

Glad you like the list of what blooms for us in our shady backyard.

Sweet William does in fact grow well in part sun/shade in my cool summer climate, so should bloom for you, too! Especially if your masterwort blooms you should have enough light.