Moonscape in Bermuda Grass

Meet our backyard.

Not a tree, not a shrub, not even a stump! -- rather boring and vacant. I don't know why the space is so unpopulated by plant life.
Sometime last summer I put in a little gardenia plant that a friend gave me. It was pitiful with dried, yellow leaves, but it's recovered nicely. That's it, in the front right of the photo below. Very little shrub, but one must start somewhere, right?

Then, you see three brown shrubs in a row. Those are old mums. For my British Isles readers -- no, those are not burial sites for deceased mothers. They are chrysanthe ... mums.

They look pitiful too, but each one has a little tuft of green -- new leaves -- at the base of the stalk. I put them in the ground Monday. It was a warm, sunny 73º afternoon. Should one transplant shrubs in early January? I guess it depends on where you live. Two of them were in pots anyway, and the third was being murdered by encroaching canna lilies in the front yard, so I did them all a favor by placing them in the moonscape. The moonscape backyard gets great morning/afternoon sun and lots of it.

Then, there is this poor thing, a euonymous. Can you see it? Its sun was blocked by those same canna lilies, and it nearly died. I'm hoping it will rejuvenate this summer, grow and spread out.

This is the plant I really wanted to rescue from the vicious canna lilies, my sole lavender plant. Will it recover and become healthy?

So there are my two little shrubs, next to a patch of weedy bricks that ought to be a patio, overrun with Bermuda grass. This area is so entirely exposed to all the other houses and people driving/walking/biking by, that we don't sit out there. It's just ... awkward. I do keep big pots of herbs and patio tomatoes there in the summer. The full sun there is wonderful and warm.

The house is a rental, so we don't want to spend money putting in trees or big shrubs, or building any kind of privacy fencing or anything else that might actually improve the living experience in our back yard, I'm sorry to say. It is what it is. So I'm trying to add itty-bitty improvements that don't really cost me much. When the canna lilies in the front yard became so dominating in that bed, I figured it wouldn't hurt anything to move the other plants back here.
I brought only one little plant, in a pot, from our last house -- a rosemary. It was nearly dead then.

For some inexplicable reason I placed it here, between the steps and the heat pump. I admit freely that I have ZERO sense of creativity or aesthetic talent when it comes to decorating with plants.
But my rosemary is alive!

We have at least another ten months in this house, so I will look forward to watching these plants thrive this summer. If anybody has any low-cost ideas of how you would improve such a backyard, if it were yours, I'm all ears! Believe it or not, this is the time of year (in the true South) to do real yard work. No mosquitoes. Great temperatures. Vines and other encroaching plants are at a minimum. No sweating. And the ground is not frozen. Just one of the advantages of living down here!