Wormwood -
Artemesia species
My favourite wormwood is the tree wormwood, Artemesia aborescens, because it has such beautiful silver foliage, and grows really well from cuttings. The plants in the picture above were grown from cuttings a few years ago, and are excellent ground cover.
These plants are great for filling in difficult areas, or hiding fences, as in the picture. Luckily, they are very hardy, and don't seem to need much care, which is great in hot dry conditions. They will appreciate a little water however.
They'll need to be pruned to prevent them getting too big and straggly, but they make great mulch.
Wormwood is supposed to be great for discouraging garden pests, and I did notice that a cherry tree growing next to an Artemesia aborescens had no pests on the side near it, although there were insects on the other branches furthest away from it.
Sometimes I put some wormwood clippings amongst the straw in the chicken coop, as it seems to repel mites. My chickens certainly look healthy! Artemesias also seem to stop weeds growing beneath them, which is always a bonus.
One thing you should watch with this species, is when you use them as mulch, they are inclined to grow, just as if they were cuttings. They are very easy to remove though, so it isn't really a problem.