4ft. hedge in So Cal - what do I plant?
Newbie here. I bought my first house last year, and with it came a backyard full of dirt - no grass, some weeds here or there, and one very large avocado tree (yum!). My first project was building a large patio with red paving bricks. I want to plant a thick 3 - 4 ft. tall hedge around the patio to enclose it, but I'm new to gardening and have no idea where to start.
The soil in my yard (if you can call it soil) is very dry and hard, so I need a hardy hedge. We have full sun in the backyard. We live in SoCal, but near the beach where temps range from 55 - 85 all year.
Does anyone have any suggestions for the type of hedge I should be looking for?
I'm also wondering how far apart to plant the individual plants. I know that it will take some time to fill out into a full hedge, but is it typical to plant them 2 - 3 ft. apart, further, closer?
Can I buy plants that are already pretty large, or will re-planting them hurt them? Maybe I need to start with really small plants?
The image I attached (pulled from a google search) is what I have in mind (except a little taller).
I obviously need a lot of help!!! Thanks in advance,