Good luck planting on that steep hill. The best thing to do is plant before weeds find themselves a home in it. There is also tulips or other bulb plants and hostas. They are great any where.

I envy you the large, mossy rocks. Phlox subulata is very effective in bloom, otherwise it's just a dense green mat. Tulips are deer candy and gradually seem to peter out. Clumps of daffodils are nice but they leave foliage to contend with after blooming. I like the minor bulbs in rocky areas - muscari, crocus, puschkinia, scilla (people love or hate those - I'm in the love 'em column). With the minor bulbs, the foliage tends to splay along the ground after blooming until it disappears entirely. Arctostaphylos uva-ursi "Manhattan" is a good creeper - greeny-bronzy foliage with pink flowers followed by red berries. Sedums of all types, colors and leaf shapes, ferns. A scant bit of soil in crevaces and succulents like hens & chicks do quite well.

Looks to be plenty of space for some blooming shrubs that wouldn't get overly large and hide the rock-work.

I would look into varieties of juniperus horizontalis which are good for holding soil; a specimen Bird's Nest Spruce would do well in a rock garden or a specimen dwarf Globe Blue Spruce.

Suppose the question that should have been asked initially is what kind of look are you going for? The potential is there for something really attractive.

Creeping Jenny is bright gold leaved with small yellow flowers, and it hugs the ground and will spill over the rocks.

Lamium has white and green leaves and purple flowers--although it does come in other colors of leaves and flowers--it grows about 1 foot tall.

Day lilies come in many shades and grow about1 to 2 feet tall. Look for the everbearing or repeat bloomers.

Hostas come in a multitude of leaf and flower colors and can be quite tall or quite short.

There are lots of things you could put in there. The only thing you have to do is decide what. I suggest you look at some landscape and plant books. There are some books specifically written for gardening on a slope.

here is a pic from 2 1/2 years ago.

Some ornamental grasses can definitely look weedy, but I think the larger and more evergreen ones tend to look less weedy. Some large evergreen sedges might be a good choice.

The little walls or borders of smaller rocks seem to me to be forming lines and a texture which is taking away from the strength of what is there.

Also thinnig or limbing up out some of the trees to the left of the huge boulder would add some more interest, as the house becomes more visible.

For plants, well it seems my favorite one recently has been leucothoe girards rainbow! Evergreen takes shade and slopes quite well.

I think you have received good plant advice, the only thing I would add in terms of grasses would be that you could try Hakonechloa macra 'aureola' - japanese forest grass. I think it was perennial plant of the year last year, its a nice low growing (18 in) bright grass that prefers part to full shade. It can also grow in the sun, but it bleaches out. I have found the color is better the more shade it gets.

In terms of design advice, my suggestion would be to pick 2 or three plant types and use groups of those. (For example 5 japanese grass, 7 hosta, 5 astilbe) That would ameliorate the small rock busy -ness that Isabella commented on.

Of course you have the rest of the winter to plan this, because although it was ridiculously warm yesterday it is too late to plant in all of New Hampshire now. At my house the ground is partially frozen.

Your idea will make for a pretty entrance to your property

My only question would be what did you do on the RHS of the driveway? You need to make sure you blend both sides of the drive rather than have 2 totally different "feels". IF it is just grass? then you can blend it in with the hill easily by putting in some other rock beds.

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