The landlord's parents spent about two years building the terraces (according to them), but didn't seem to have any great plan in mind or even a layout idea of what plants would be where. As most of the retaining walls are merely pressure-treated wood with rebar bracing them, it's not surprising that some are bowed out with plant life pushing open gaps. The northwest corner of the yard didn't get even a couple of terraces, so it's a slippery hillside. I'm mostly dealing with the northwest section as it appears to be the least tended, adding at least two terraces and one stone retaining wall. There are two "garden boxes"... they're not so much raised beds as mini-terraces I've boxed off to grow veggies. Farther up the hill against the back fence is the original area I turned into veggie garden, this year expanding farther over and letting the chocolate mint take the lower edge of the older box. I'm planting pieces of chocolate mint in the clay along the steps I've made in hopes of it 'taking over'.... I'd rather have mint as a ground cover than mallow and those nasty burrs any day.
Also this year, I've expanded the 'poolside' garden box by removing all the plants from the edge of the stairs to where the strawberries were from last year. The strawberries survived the winter (I let the clover grow and protect them during the rainy season) and now are producing strawberries -- not many, as I still battle slugs, bugs, and birds to get to the fruit before they do, but we're getting a couple each time now. The rest of the box has a row of corn , two rows of onions (mostly gone now as I've pulled up the ready ones), a small sage brush, a couple of basil bushes, and heirloom pumpkins growing behind the corn. While I intended to do that, they kinda started without me.... I had the seeds from last years' pumpkins on the cinder-block wall to dry out, and a couple of windy/rainy days this winter got them sprouting, both on the wall and down in the garden box. An iron trestle and some garden wire is helping them grow vertically... one very happy pumpkin plant is even using a corn stalk to climb up the wall.
So now, I'm trying to get the drip-system installed and working in my hillside area.... it appears the landlords' parents had installed something similar, but since they buried the lines there's no way of knowing where the zones are placed and many of the lines are broken. If I could find where their system is hooked into, I might be able to repair it. Meanwhile, though, my little hillside never had those lines, and unlike the previous installation I intend to keep my water lines above ground where I can see them (and not cut them accidentally by digging). I also picked up some 'insta-flower' mats to cover the one section of 'pristine' hillside I'm not going to try gardening this year. Something to encourage the hummingbird family that hangs around, and hopefully add some stability to the nasty clay -- currently it's bare save for some sedge grass, which is almost as slippery as the bare-clay hillside.
We've gotten permission to do "whatever we wish" in the backyard, so in the next few weeks we are probably going to remove the giant banana tree that hovers by the house. It's in a bad place, and banana trees don't thrive in this climate -- in spite of any help the hummingbirds try to pollinate them. The side of the house is another rehabilitated area: aside from the banana tree, a lime tree, and the spearmint, all the other plants have been removed or relocated in favor of planting tomatoes and onions. This area is Bennie & Sue's little garden, so I only deal with it occasionally by watering the dwarf orange tree. This year we cleaned up the corner near the gate, which had a decrepit utility shelf holding pool supplies and other junk. After clearing the trash away, we pulled up the wooden boards and now it's bare dirt with some weeds growing in it, but it'll be turned into more garden in some future time. As for the boards, I carried them up to my chunk of hillside to use as part of the retaining wall-cum-garden box. Slowly but surely, it's looking less like wilderness and more like a garden.