The foliage is about a foot tall until the flower stems start elongating. In my climate it is evergreen but I usually trim it back because it is pretty scruffy in winter. The leaves are fairly large and coarse but unobjectionable imo. You can see them in the picture. Until they flower that foliage is a bit shorter but you can see the general appearance here.

I find the foliage attractive the entire growing season - lush mounds of rich green foliage, reminiscent of maple leaves, unbothered by pests or disease. It stays a foot or less in height (usually less in the areas I have it planted, maybe 8" or so). The flowers are borne on long, thin stalks as shown in the photo above - a nice airy effect when in bloom.

I am a huge fan of Japanese anemone. Can't imagine a garden being complete without them :0)

I have 'Honorine Jobert' in northeastern Pennsylvania zone5. Foliage emerges mid-spring and it is starting to bloom now. It spreads and overtakes other plants in my partial shade garden with rich soil. I pull out 1/3 from here every year.
In a sunny bed with no amendments and only thin mulch layer,1/2-1", it does fine. No invasive traits. I have to do nothing with it.
Leaves are med-dark green, thick, 3 palmate toothed margins and get about 3-4" diameter.
Blooms are so pretty, I thought it was an artificial flower the first time I saw it-pristine white petals and vibrant yellow stamens surrounding pale green center.

This plant is beautiful but don't plant it too close to other perennials because it spreads over time with tenacious roots. I have been pulling out leaves and roots popping up all summer from a huge plant I dug out this spring. The root of the main plant was 3" thick. It keeps putting up leaves all over a 4 foot space and I pull them everyday to try to get rid of this.

I planted it out in a meadow where it can do what it wants. I love the flowers but the bloom only lasts a few weeks and isn't worth the space it takes up in my average size garden. Leaves are nothing significant, just green. The flower stems are very tall even in full sun. Where I live it dies down over winter with ratty looking leaves, and I have to cut it back to the ground.