I would consider ornamental grasses as the main plant species since it is full sun. There are some smaller ones such as Blue oat grass (Helictotrichon sempervirens) that might work. You could include some taller ones as an accent every 8 feet or so. You could also include a conifer or different type of plant as an accent. The full sun next to the driveway is going to require a tough plant. Here is a link that might be useful: Plant groups This post was edited by ja-gardener on Fri, Jan 18, 13 at 22:28

ColMuldrow, I think you have had a lot of suggestions here for things to do IN the beds and you were looking for things to OUTLINE the beds. No one has really addressed the virtue of your idea of outlining the beds, and I think the message in that is that outlining them may or may not be a good design decision. Could you maybe tell us what is driving your desire to outline them? That would assist in a design discussion... this being a landscape design forum. And in design, purpose often drives decision-making. For me there is some confusion, as I may have suggested in my post, between the image of what you have, and what you want to achieve. What you have is kind of hard to argue with, and because of its dominant nature, trying to put a different kind of landscaping underneath it would have a bit of a futile feel to it. And so, a tidily outlined bed would have a slightly surreal feeling to me in this setting. It is obviously your yard and your preferences will prevail, but given that you've chosen a landscape design forum rather than either a plant forum or a local nursery for advice, I'm afraid that does drive the kind of advice you'll get (unless the conversation turns to ivy...). That said, there are not many plants that will stay exactly where you want them to in the conditions you have here; at least, it may depend on the trees, but I don't think so. Plants travel in response to where they find moisture and light and nutrients. Areas under trees are notoriously short of these attributes, and you may find a carefully planted edge wandering from where you laid it. That is why I suggested a physical edge, which if nothing else would create moisture-retaining areas in the soil that would keep plants inclined to stay where you put them, and allow you to correct if they wander. Yardvaark, I thought we were all going to try to get along. The key to doing that is, I think, in your last remark where you characterize opposing advice as an attack. It is not, and regarding it as such will always lead where this thread has led. Opposing advice, even if it criticizes advice previously given, is just the way the cookie crumbles when you ask a room full of people who are not an organization or hierarchy of any kind for advice. You will not get a single answer, the answers may disagree, and as the asker, you simply have to sort that out and the people in the room have to come to terms with being disagreed with. You could have opposed my advice to use ferns on some basis, and I would not have regarded that as at attack on me, but rather as contextualizing the advice I gave the OP. I might have responded, or reiterated, but probably not if I thought your additional advice enhanced the OP's ability to evaluate the option. I don't regard it as an attack on me when someone denigrates my ingrained aversion to foundation planting; I simply see it as a good thing that the OP gets a variety of advice. If all else fails, we should all be addressing the OP, and not each other. Karin L

A lot of things will grow well in those conditions. The gravel base makes for excellent drainage. If you were planning to add soil as well- as in a slightly raised bed area-- that adds further. It also depends on what you have time & energy to do- so you don't " hafta" remove it if it's easier to work with it. You can also do some of both , depending on your planting design --it's not a toxic material, it just has some impact on the soil and moisture conditions.

If the current and future gravel is crushed and not rounded, then I would think the 4 inches would be adequate. If the stones are rounded, then no depth is adequate. I have crushed stone drive. The stones are pea gravel sized but they are faceted and not round. Once they are locked into place, they don't move around. Mine does not have a border, either.