I think a lot of CA natives will grow fine with nearby summer water. I know salvias such as black sage (Salvia mellifera), Cleveland sage (Salvia clevelandii) and many cultivars or hybrids of these two would do fine and both are in the purple or blue range with grayish foliage. Orange Monkeyflower (Diplacus aurantiacus) would also do fine, and of course has orange flowers. They key with more sensitive natives is exactly how far from the water they are planted. I understand that extra summer water can make some natives shorter lived than they would be without summer water, but in the short term (first three or five year, at least) many will grow better with a little moister soil. i think if you are five feet from a drip irrigation line, you'll have fairly dry summer conditions, depending on how much water is dripped and which way it runs off, and if you're ten feet away it should be almost as if there was no summer water.

I guess if it was me I wouldn't hesitate to use most natives as long as I kept the more water-sensitive ones at least five or ten feet from the irrigation. Most natives I'd plant within a couple of feet and not worry about it. I am willing to risk the chance that a plant like a ceanothus will die in several years, as long as it grows well in the mean time.

I think sages are a good idea and I would throw S. leucophylla and S. greggii in as possibilities, although neither is a CA native. Lavateras and rockroses and gauras would take the full sun and variable summer watering and clay soils.

Some salvias, cistus (rockrose), and teucrium all do well in my transition areas. I also grow thyme, lavender, penstemon (some varieties are thirstier than others), buddleia, rhapheolis, westringia, and bearded irises (flowers will be smaller than you're used to) in my transition areas that get some irrigation; careful planning is important, because some of these are thirstier than others. I have not yet planted one, but I'm planning a cercus as a small accent tree. The drought tolerance of new zealand tea tree is highly debateable.

I'm somewhere between zones 18 and 21 with a big south facing sunny slope. Ceanothus looked like such a natural for me (blue flowers! beautiful! no water!) but I've never had any luck, and the ones I see in the wild are all on north facing slopes.

What does work on the hillside (absolutely no summer water) for me: Matilija Poppies! oh I love those big fried egg flowers! Echium, aka the butterfly resort; sugarberry rhus; creeping acacia, although far from the house because of the fire potential; toyon (aka the "Holly" in Hollywood), oleanders (yuck), various trees. Some years the California poppies work and some years they don't. I have a severe rabbit problem so my plant palette is more limited than most others'. For your mediterranean look, a fruitless olive might be nice.

If you're new to Cal. natives, it is critical to wait until October to plant them. Go to Theodore Payne (or its website) now to look and plan, but don't buy until October. Good luck. Our natives (and the plants that harmonize with them) can be beautiful.

All Great suggestions. I do already have a lot of Salvia Gregii...mainly because everyone sells it! I really would like to add some Penstemons and def. Cleveland sage. I do like plants for the B, B, & B's. I do have some cuttings that are doing well from a Butterfly bush, that I was not sure where to put (problem solved)...so good idea there. I love the flowers on the Rockrose... too bad they don't have a longer blooming season. Some of the flowers and plants suggested I am not familiar with, so I am off to do some research.

Thanks Again!
Las Pilatas says natives can be planted anytime... I do not have alot of natives... but do have a big slope I want to plant them on. I think it is pretty much North Facing.
I have had the same problem with some CA wildflower seeds I scattered...actually I though the rabbits and birds got them all and low and behold 2 springs later... I have a mass of desert Bluebells, some Lupins and a few CA Poppies.
Bearded Iris, I have a ton of! Well from all the suggestions, it looks as though I do have a few things I can move from other locations or transplant in that area...then with a few (Ha Ha) purchases from the nursery... I will be set! Easy Huh... Just give me several hours of backbreaking work digging planting holes in my wonderful Rock & Clay!

Inkneedeep, the reason, I believe, that bluekitobsessed recommended that you wait to plant natives until October is that most natives are going to go dormant or semi dormant in the summer. They do this to conserve water. Their "spring" is really fall. If you plant now, your young plants won't have had time to develop a root system that will sustain them through the hot, dry summer months.
Young unestablished native plants DO require regular water until they are established. And yet, natives cannot take too much water in summer or they can rot or the moist, hot soil causes pathogens to grow.
If you wait until October or even November, your rate of success will be much better.

Thank you for the clarification, buddyben! That totally makes sense!!!

You mentioned wanting yellow. The best native yellow is Dendromecon Harfordii. It does not mind a little water. The flowers are bright yellow and the foliage is gray green. Plant this next to where you sit so you can enjoy the fruity fragrance of the flowers, Once mine got established it blooms most of the year.

The bush poppy is a good choice for yellow flowers. Another I forgot to mention is Tagates lemonnii, lemon marigold, which is undemanding and always gives me bright color in summer and winter, but some people don't like the fragrance.

Here's a Jerusalem Sage that has circles of bright yellow flowers. It's a lot like my purple native sages. It's beautiful. I found it at Rainbow Garden Nursery on Grand Ave. in Glendora, CA.

Here is a link that might be useful: Jerusalem sage

I love that phlomis (Jerusalem Sage) It is one that jumped in my cart when I was at Peppertree Nursery in Wildomar a couple of months ago. I planted it in one location, where it just didn't work...looked lonely and out of place, so I have recently moved it to a hot, low water bed in the front yard with some Mexican Sage,Purple Fountain Grass and some purple and yellow Lantana... I like the combo... The Purple fountain grass really makes the Yellow of the Phlomis "Pop", Although as usual, I may have crowded things a bit close together. Also I may use the Purple Fountain Grass too much, but I love the way it showcases other plants, as a background.
Dis & Dicot..Thanks for the added suggestions...I think those are great too and have added them to my ever growing list! Today I am going to try and get some of the dirt in that I need to get this area finished. Wish I could quit my job and spend all my time in the garden!!!