Clary
Impatiens love cool conditions some morning sun is good but not hot afternoon sun. Impatiens as a whole come from montane forest or cool summer areas where they get a good amount of rain. Many of the bedding type have been bred to take more hot climates then they would normally grow in. You may want to try adding a water polymer to the soil so that it will absorb the water and release it slowly back into the soil as it drys. They will love you for it I am sure.

Hi
I grow them as a winter annual One way I've found that works for me is to get bags of topsoil from HD and mound it above ground level and plant directly in this with no fillers.Seems to hold the correct amount of moisture as long as the "dry" season doesn't flood lol
I'm not sure about freezes but find they tolerate frost quite well. I'm not sure how cold you get there but you could cover them with a sheet.
I plant them every year as they are spectacular during Dec-Feb.If the "dry" season is dry and the temps are anywhere "normal" lol
Gary

Hi Clary, I live in Mobile, Al and probably have the closest to the same conditions you are growing in. Impatiens will NOT overwinter in the ground here, you should take good strong cuttings now and root them in water over the winter, after the last frost date (here it's around March 15th) plant them in your garden; make absolutely, positively sure that the roots are not sitting in any amount of water for any period of time, they would rather die than have wet feet and they do. My impatiens look wonderful all summer, they never pout during the whole time. I have fed my beds with lots and lots of oak leaves, live oak has the best leaf shape and "heft" for the purpose, they do not blow about and look really nice when a thick carpet is laid down. I NEVER, ever let them try to stand up the the sun in this climate, they would fry in a heartbeat. NO sun at all is really best, but dappled is ok too.
HTH

we had our first frost this morning and mine have finally been put to rest for this year.
they have actually naturalized for me. the latest seed pods scatter about under the leaves in the beds (all under trees) and return next spring. i have not bought plants in many years. i guess they are the i. wallerana type; those six-packs you see at garden centers each spring.
hard to beat for color and length of bloom.
maybe you could try them from seed, clary, letting them establish themselves where conditions are to their liking.

Bright shade, or morning sun/afternoon shade, a continuous supply of moisture, and temperatures below 80F. They thrive! Mine will grow into mini-shrubs a couple of feet high in a good summer. All dead now from a few frosts.

It sounds like it is too warm and dry for them in LA.

shrubs-bulbs--My husband used to get quite a bit of mail from the UK which went to him by way of L.A.--that's Los Angeles. We live in LA--that's Louisiana. While we are both pretty hot in summer, it's not dry at all here; I haven't gardened in southern California but I do know it's not humid at all, as it is here, and cools off at night to the point you need a sweater if you're going out in the evening, which we don't here. A lot of people here grow beautiful impatiens, and the idea of 'not over 80' means, if we're lucky, at night. They seem to be pretty adaptable, at least in the more common bedding kinds, including double and variegated forms. Don't know about the giant ones in a previous post. And I grew some less-common ones too that did well. I hope I don't sound snippy--it's just we have such varied climatic conditions here. The only part of the U.S. with a climate like the U.K. is the Pacific Northwest, where I started gardening, and subscribed to English gardening magazines because U.S. ones didn't relate to where I was. I'm just jealous!

Oops, wrong coast! Anyway, I still think it might be too hot. I wonder also if they are getting overwatered? They will rot off in very wet conditions and just keep getting worse however much water you add.

It gets up to 38 degrees here and often 80 percent humidity (classed as sub-tropical) - mine look great at the moment growing in dappled shade. They wilt when dry and perk up when watered.

I've been successfully growing them in the ground for years. Actually, they love this climate. In New Orleans, they do best in deep shade. The ones on the north side of my house apparently grew wild from seed, because they are growing where I didn't plant them!(and a new color...a cross between the red and pink....very pretty) Very soggy location, right by the condensation runoff from the air conditioner. In my raised beds, I put some of the polymer crystals to absorb water, but they sometimes get droopy and I have to water in between rains. Make sure they don't get afternoon sun in the summer, or they will get leggy. As long as we don't get a hard freeze, mine stay around yearlong. Even if it does freeze, they usually come back. If they get leggy, just cut them back.

Ok, an answer from someone that lives in a hotter place than you do and loves impatiens, common impatiens withstand practically every kind of sun exposure, from full sun to full shade, what they can´t withstand is lack of moisture. The catch to have them in soaring heat conditions, like the ones we have here during spring with temps from 90-110 F, is WATERING. I water my impatiens twice a day, early in the morning and at mid day ( 2-3 PM ), that way they survive full sun exposure. For us they are perennials and only need a haircut in the middle of the winter.

Raul I did a test and grew impatiens in full sun just to see if it could be done,and yes they needed watering 2,3 times a day. They never looked as good as the ones growing in the shade, they had hardly any leaves,only a few tiny ones, and all the branches were a reddish colour,compared to the green branches from the mother plant. It didn't grow tall either. Although in winter it did pick up and actually look better in appearance,so I moved it into shade the following spring,and now the new growth is the usual green,and after a prun it looks like new.

The new seashell impatiens hardly flower in full sun. My regular impatiens do better the more sun they get, provided they survive, not that my sun is anywhere as near as strong as most on this thread. I plant them in just a few hours of morning sun because plants in my garden have to mostly fend for themselves or perish :)