If you don't have a rock wall you can improvise. Here is an idea I saw. Buy several chimney liners, they are orange like clay pots and several inches across by about a foot high. Stand them on end, fill with soil and plants. If you want two levels just bury some in a trench partway up.
Make a false rock wall
Sis, building supply stores - we bought a whole chimney's worth last fall! I'm using the outside chimney blocks from the old chimney - there were 4 that didn't break - for garden seats, stand them on their sides and voila, a seat with 2 different heights possible. The liners are just heavy clay pots with no bottoms when you set them on end.
Mary, that's a great idea. You could dig them in at different levels and have something that looked like a pier.
I saw them along somebody's sidewalk and they were overflowing with plants that draped down their sides. If you have a slope you could put a row or 2 of them on the lower side and it would look kind of like a retaining wall.
Another thing that works for planting in areas like this is those big cement pipes. Some of them are 2' in diameter. You might find slightly damaged ones at construction sites where they are burying them. They are very heavy and you will need some help to bring one home. Stand them on end and fill with soil and plants. These combined with chimney liners and other odd cement "planters" that were designed to be used for something else would make an interesting wall. If you go to a lumber yard they often sell things like decorative blocks, think "planters" when you look at them.
BINGO' Have been thinking this over and came up with a great idea' We installed a timber(2ft high)16x5 planter. We haven't planted anything as it is under our very large sycamore tree and didn't want to cover any roots with soil' Thank you for that suggestion' My alpines should be fine now' What do you think??
sis, most alpines like full sun.. think of where they would live in the wild, at the top of mountains with no shelter from the sun! you could put in some shade loving plants like hardy geraniums or ferns, they would be great under that tree.
I have a plant that I think is called Snow in Summer that grows under a tree with just a bit of sun now and then, mostly dappled shade. It has small greyish leaves and white blossoms, it was planted behind a rock edging and draped itself over quite gracefully. Vinca minor grows next to it, did the same thing, has purple flowers. There must me more.
I'm about to make some raised beds that look like cut stone. I got a load of broken sidewalk slabs ( square and made of concrete) know what I mean? these will be cemented together with the rough broken edge facing out. when it weathers down it will look like they are made from stone.
Mark