Most of the regions you listed have similar rainfall patterns as Socal - dry summers, wet winters. As long as you group them for their drainage requirements, and for the Aussie/SA plants - fertilizer requirements, you'll be fine - and for OZ/SA, that means no phosporous, ever.

You may want to do a 'jar test' to see if you truely have clay (which retains water, and is nutrious but needs to be amended for drainage) or if you have a mix of clay, silt and sand. If you don't plan on improving the drainage if your soil is compacted, the list of plants will get short.

Keeping them under 4' will be a bit of a challenge, as many shrubs like to get larger than the tags suggest (plants can't read). It's actually very easy to have a non-stop bloom in a drought tolerant landscape, although it takes 2 years for everything to really get established.

Suggestions are
california fuchsia - Zauschneria californica (cut to ground in winter)
rosemary
cape fuchsia - Phygelius
coeropsis
rudbekia
day lilies
some banksia
grevillea
leucospermum
kangaroo paws
crinum
australian fuchsia - correa
sollya
callindrenia (sp?)
salvia
penstemon
Perovskia atriplicifolia - russion sage
Artemisia
Cistus
Ceanothus
Caryopteris
Gaillardia
Galvezia snapdragon
jeruselum sage
Odontonema Strictum
Eryngium
isopogon
Helianthemum
Kniphofia
monarda
Monardella
mimulus
Lobelia laxiflora
lavenders
Tithonia

and that's just a bit of what's in my garden. Twice a week, all year, I cut a bouquet for the house.

There's a lot of wonderful 'peas' from Oz, but they are difficult to find in nurseries, and can be challenging to grow.

I maintain a running list of what I've planted and others that I'm interested in (all drought tolerant) with plant specs and care. You are welcome to a copy - just pop me an email.

=^,,^= diana

Agapanthus are from South Africa, rather common, but nice blues and white. Anigozanthos/kangaroo paws, from Australia, nice reds, rusts, yellow, about the right height. Are you not from around here? This is prime Mediterranean climate for everything you mentioned. Also look up Grevilleas, Arctotis, Leptospermum, Protea or Leucadendron (can be difficult), Bougainvillea, Gazania, Osteospermum, Kniphofia, too many to mention them all.

Go visit some of the local botanic gardens such as Quail in Encinitas, the Huntington or Los Angeles County Botanic Garden, etc for excellent visual examples of mixing medit climate plants from all over the world with succulents, which the Huntington especially features like no where else.

Best advice for planting these is to do so in late fall with start of fall rains, so plants get established at the coolest and wettest time of the year. Ever so much better for getting these plants off to a good start, and saving water besides...

I am presented with similar problems, but am in Bakersfield, CA, not LA. In BKF, things are even more scrubby and sandy.

I know however, that simply saying LA, does not mean mediterranean climate. LA is a big place and has several regions or zones with their own micro climates, depending upon whether you are close to the coast, inland or at a higher altitude up the side of some range of hills or low bergs ( mountains ). Heck, after they changed location of a weather monitoring station in LA, they found they had to change it back because the new location, completely threw off the mean temps and rain fall averages. If you are near the coast and have that Santa Barbara-like zone 8/9 weather, I envy you.

But what I am going to suggest may get me some hisses and cat call rejections from the bleachers, but let me give you the reasoning ...

Every well populated area uses hired landscapers. They in turn, know what will survive in the area and what won't. Further down that economic pipe are the suppliers, nurseries and the local gardening section of stores like Home Depot, Orchard Supply, Lowes, Wal-Mart, Target and humble K-Mart. If it sells, they stock it. There is no demand for plants that die.

Go to Home Depot or Walmart and you'll find that they even separate out the house plants and keep them indoors while the outdoor thrivers are ... fancy that, out in the outdoor area. Does that help to give you some clues about choosing outdoor plants?

It's when you order stuff over the internet that you can get in trouble. In those cases you get unique plants, but you take your chances whether they will thrive in your region. Going down to the HD or WM gets you some assurance based on experience and demand for plants that thrive in your area that you'll get exactly that. However, you pay a price. Your neighbor's plants will often look exactly like yours.

;-)

Might I suggest something that you probably can order over the internet and have it survive there in LA? Pacific Iris and the further north, Douglas Iris, the wild flower varieties of Iris native to the West Coast. These critters can flower in several color variations and are just the height you are looking for. Douglas Iris however, are always lavender colored. It's the Pacific Hybrids that vary in color.

I've found just the opposite from the big box stores and their "nursery" sections. I can't count how many plants I've purchased in the past from Home Depot, etc., only to have them suffer greatly and (usually) die, mainly because the plants had no business being sold in my zone(s). However, these stores are GREAT sources of cheap, popular annuals!

Locally owned, well-established, neighborhood nurseries have rarely steered me wrong, not only when it comes to knowledge of plants they sell, but selection, as well.

And that's 2 bits worth of my opinion. :)

Brenda

another voice from the bleachers...
Bog box stores grow plants that look good (right out of the greenhouse), remind people of where they grew up (one-shot tulips and suicidal gardenias) and propogate easily (invasive), but Brenda's spot on about annuals.
But back to the question... Bahia's suggestion to visit the nurseries will let you see not only what the plants looks like, but if they fit your height requirement. My garden has 8 protea, 6 leucospermum and 4 leucadendron, but they each topped 4'-6' in less than 3 years. Like Bearstate, I'm cautious about ordering over the web, and considering the fine quality of nurseries around here, don't really see the need. However, I've ordered daylilies off ebay with great success and cheap prices. =^,,^=

Here's another vote to avoid the big box stores whenever possible - too often the plants they sell do not, in fact, do well in that area. Patronize your local, independent, mom-and-pop nurseries because these folks make all their money from plants and not from a huge variety of hardware or household products, etc. Locally-owned nurseries will almost always have far more knowledgable and experienced staff who wouldn't want to sell you anything they don't think will grow well in your garden and who can take the time to find out what your growing conditions are.

There are lots of good books out there about gardening with California natives (one I like a lot is "California Native Plants for the Garden"), and also about Mediterranean-climate gardening. You can take classes at the L A Arboretum and learn what will grow well for you, or just visit there and take lots of notes.

If you like the look of succulents, which thrive on almost no water in much of the LA area where winters are mild, a good new book is "Designing with Succulents" by Debra Lee Baldwin.

Also, check out the Southern California Horticultural Society for their montly meetings, most of which are free. It's also a great way to meet other passionate gardeners. Their next meeting is July 12 and is about native plants.

Finally, look for suggestions at www.TheMulch.com

Here is a link that might be useful: Southern California Horticultural Society

Thanks folks, for your HOs on big box store garden center plants. Yes, nurseries are the better choice, I'd always thought, although I've seen some really poor nurseries too. But if you can find a good one, you can find good advise and plants there.

My own experience with big box stores however, has not been bad ... but then, I'm usually not looking for simple flowers ... more of the exotic, sometimes big, permanent stuff. I do make use of a landscaping service and I know that they source from both nurseries and the big box stores, depending upon what they require and in truth, I know that they cycle certain plants through certain places, depending upon the season. But then, this property is too damn big for me to be trying to get down on my knees and plant every little sprig.

You can find some things at the big box. Don't totally count them out. And as for the internet, well ... there are things that you can special order from your nursery, but not from the big box and then too, there are things that you can only source over the web. Just try finding those Iris Douglasiana down at the big box or the SoCal nursery ... you likely won't or will have to special order. Try special ordering certain bamboo plants ... and you'll quickly find that the Internet is your only option.

Seeds? The internet is your best bet for exotics and some heirloom and other types.

So, keep yourself open and try all the angles. My point is that you can generally get a feel for what does good in your area from the economic forces at work down at the big box ... or at your local nursery.

Cheers!

As far as fruit trees are concerned I see the big box stores selling some trees completely unsuitable for southern California due to the high winter chilling requirements. The one advantage of the big boxes is they usually give you a one year guarantee which many private nursuries won't.

Kathleen:
You might find it fun and interesting to visit Worldwide Exotics growing grounds in Lakeview Terrace (off the 210 fwy near Sunland) where they have lots of Australian, South African, Central American and Mediterranean plants. They are also uncommonly friendly and helpful. I am not a shill but half of my LA garden is from Worldwide's grounds. (818) 890-1915

I also believe in the neighborhood shops! I find it so funny to see many of my neighbors plant the same annuals they or their gardeners bought at HD or Lowes. Smaller nurseries have a different selection you just have to go out there and search for them. Pasadena has a great succulent store called Cactus Center. May I also suggest taking classes/workshops like at Descanso Gardens or the Arboretum in Arcadia. I just found out about a succulent workshop on July 22 posted on Craigslist in the Venice Beach area at In The Mix!