Alex, there is an extremely talented gardener here in my area who has done some gardening similar to your zone - although I haven't seen her posting in the last few months. I attached a thread she responded to a while back about growing hydrangea in the Laguna area. 'Macs' - hydrangea macrophylla. But, be warned, if you are not seeing them at all in your own neighborhood, there may be a reason. The florist type hydrangeas you mention are varieties of hydrangea macrophylla. Sometimes they are perfectly acceptable planted in the garden in mild zones like my own 8b....after being acclimated to being outdoors, these are greenhouse grown plants. The problem with them is they have been bred and raised for the flower trade, and grown under a strict regime of fertilizers, hormones, lighting and temps so that they will bloom to coincide with particular dates, like Valentines Day, Mothers Day etc....often grown with no regard to long term plant health. Sometimes they recover from the treatment and do well, other times they do not. If you were to receive one as a gift, I'd say go for it and plant, but if you have a choice, choose regular nursery stock, not florists stock for your garden. Your seed choices look good with a couple of exceptions. Hellebores sown in Feb may take 15 - 18 months to germinate. They need to experience a period of warm moist, followed by a somewhat lengthy moist chill, then will germinate while conditions are still cool. If I sow them fresh by Aug/Sept, I will have germination approx March into April. If you were to ask around June, someone could probably send you fresh seed (like me) that you could sow - much more reliable than dried commercial seed. Alstroemeria can be similar, they self sow like crazy in my garden, can be stubborn or at least very slow (many months) from dried commercial seed. And do you know they go dormant around August, leaving a blank space in your garden? The hummingbirds love them while present, but they spread, become a little messy, disappear until Fall rains begin or the weather cools. Here is a link that might be useful: Hydrangea, California

"Tiny Towers" Italian Cypress are superb for tall and narrow. They don't get gigantic like the big ones do. Spearmint Juniper is also great. Beautiful green color and takes to shearing very easily. "Purple Pony" purple leaf plum is also excellent as a small tree. Only gets about 12' tall. Doesn't get huge like the big ones do... There are also some smaller Cassias that do well as small trees and have nice flowers as well and are only briefly deciduous.

Poppy cock I say to the liquidamber haters. Different strokes and all, but to me the beautiful fall folliage is every bit as breathtaking as any flowering tree. Yes, the balls are ouchy, so not recommended where one might go barefoot. Yes, the roots can show above ground, but not very noticeable except in the most pristine lawn. Our forty year old neighborhood also has many near the sidewalks and none are damaged at all by the roots. Not sure, but believe the rotundaioba are quite slim and look best planted in duplicates. You can keep your fabulla-tabula. :). I'll always love my LAmbdrs best! Below are my two and neighbors behind. They " bloom" from late Oct. Thru late December.

Don't listen to the guy above about ditching the arches, use them to make a new orleans style courtyard out of them, google "new orleans style courtyard". Put a small water feature on the patio. I would then drill in some eye ancor bolts directly into the brick and use some wire to train 5 bouganvilla "20$ each large", Purple, Red, Purple, Red, Purple going up the brick and espalier them off to the brick. "est 150-200$" Take that windmill palm to the left, remove the ciruclar pavers, take the bed about two feet wider, replace with a tan rock to match your house and use fabric underneath "est 50$". I will also say something, so many people put shrubs and trees right up against the house and its a huge no no more often than not. You can use stratigic stuff like cannas, dwarf promgranite, ginger, etc to get the same look of whatever your going for without blocking your view from the house. In saying that, I think you need to have something that gives your house some mystery. That large tree is a huge focal point. I also don't like the hedge in the front which kind of looks like legustrum. I agree with the bottle brush row between the neighbors house out the right side as I think it would be nice to have the privacy. I would go from the large tree to the black driveway and take the grass out from there to the street. Then would add in daylillies, coleous, sweet potatoe vine, birds of paradise, amongst other things. I would also put a couple of orchids on the iniside wall of the arches so you could see them from your house.