What is the exposure? Sun, shade? How close to house? I think one specimen tree would be best, such as a dwarf citrus or a Japanese maple ( heat tolerant ). I would visit an independent nursery ( not HD, etc.) & ask for suggestions.

Here’s our Desert Museum Palo Verde, no way to keep it pruned to your space. There are some a little smaller but thorny varieties still to big. How about an arbequina olive? They are a smaller tree and beautiful in pots.

Look at Ceanothus, California Lilac. It has varieties in different sizes and can be pruned into any shape. Deep green leaves all year with blue flowers in spring. Drought hardy.

It would be nice with creeping Rosemary to hang over the sides and has blue flowers too.

@K Laurence This is facing East and gets full sun until about 12:30 pm. The rest of the day is in shade. I guess any tree would eventually peak up above the roofline and would get intermittent sun until sunset.

If I do use a tree, it would be nice to find something evergreen, or if deciduous then something like Palo Verde where the shape and bark color alone are interesting.

The Palo Verde, ceanothus and olive ALL require full sun exposure to do well. And the Palo Verde simply gets too large (also rather short lived).

Japanese maples are ideally suited to container culture, prefer a site that receives afternoon shade, are well-suited to your climate, often have a very sculptural growth habit and come in a vast range of leaf color, bark color and sizes. I'd start my hunt there.

luma apiculata, aloysia triphylla

@suzy jackson Luma apiculata is a gorgeous tree but it gets to 20 feet so it seems large for that container? Do you have any leads on a mail order nursery that has at least a 10 gallon specimen?

@tracefloyd Do you have a vendor who would stock mature specimens? It looks it starts out as more of a shrub and matures to a tree. I want something with craggy stems right from the start.

It's not a tree, a bush that can grow to 10-15 ft depending on the specimen. Every local nursery in the Bay Area will most likely carry them and advise. I think I remember seeing them even at Orchard Supply in bloom.

Don't know your location, If you want a native plant nursery, in Half Moon Bay in the greenhouses on 92 mile or so from hwy 1. Also one in the Berkeley/Oakland Hills. Used to be a smaller one San Antonio near Middlefield, Mountain View... could still be there. These are the ones I've been to but not the north or south bay.

Here you can see how some have been shaped. The last phot is a picture of how dense and green the foliage can get as a hedge.

They are not real slow growers so you can work on the shape yourself over time. If you get a large bush you can clear out smaller inner branches to get your effect with some bare trunks, so if your find one with many trunks it will take well to light pruning.

Make sure it is an upright variety with deep blue flowers. It blooms on old growth.

A tree is going to become very unhappy in that planter before too long, there will not be enough space for roots, soil etc.

That is not true! With proper care, including regular root pruning, soil refreshing and fertilizing, a tree can live indefinitely in a container. I have a full moon maple that has lived in a container for more than 25 years.

Of course not Valley Oak lol, but smaller JM can thrive in pots, just don't let them dry out since they are not native to California climate in pots can dry out quickly.

Most plants that mature to 15- 20 feet will not grow to full mature size in a pot with constrained root systems. The Bonzai effect --keep them trained to eave height.

Can you pull the pot away from the wall a bit for more room for the canopy and more light?

@AC M That planter is over 40 inches wide at the top. It's enormous. What I think is a more correct statement is that a tree may never reach its full potential in that pot. But you can use that to your advantage. I like the selection of Chilean Myrtle Tree mentioned by its scientific name below, and in the wild that tree might someday get 20 to 60 feet tall. In a container it probably won't go beyond 10 feet, which is where I want it.

@gardengal48 (PNW Z8/9) How often would a tree that grows to 10 feet need to be taken out and have its soil refreshed and the roots pruned? If that does not happen, then eventually the tree just starts to look malnourished?

@tracefloyd I can pull the planter a tiny bit from the wall of the home, but I want to select the plant and see what its growth habit is first. Some plants will grow only on the Sun side.

" How often would a tree that grows to 10 feet need to be taken out and have its soil refreshed and the roots pruned? "

As always, there is no simple aswer :-) It depends on the tree, the size of the container and the soil media. I root prune and refresh the soil in my potted trees every 3-5 years (sometimes more often).

Do NOT plant a tree that can grow to 60' feet tall...it will be very unhappy as mentioned. When someone says tree, they mean a tree of up to 10-15 feet max at full mature height and can take to pruning to keep it under the eaves. Some max out under 8'.

That's why I mentioned shrubs. You could look at bottlebrush, manzanita, toyon that are non-deciduous and trained to a small tree. They will lean out into the sun naturally. If this is truly deep shade then Japanese Maple is what you want but make sure it is on a watering timer unless you are home a lot to water it.

Go to local nurseries, not big box stores, and ask a lot of questions.

Planting trees in containers is a natural dwarfing process. A tree that grows to 60 feet tall planted in the ground under favorable conditions will never reach 60' in a container!! Think of it like a modified bonsai process. The only thing that actually limits selection will be suitability to the existing light conditions. And how easily one can handle the tree for required maintenance.

Sorry- it borders on lunacy planting a tree as large as an oak or eucalyptus or monterey pine in that pot.

Various sources indicate otherwise:

https://www.hardy-eucalyptus.com/how-to-grow-eucalyptus-in-a-pot-and-keep-it-alive/

https://www.houzz.com/discussions/6035969/should-i-grow-live-oak-in-a-container

Okay... but they did say dwarf to medium size is the best.

OP does not seem to have the experience for a very large tree, and I know I am way too lazy to keep a huge tree in check lol.

Acer dissectum variety will have lacey leaves. 'Waterfall'.

Acer shirasawanum Moonrise Japanese Maple | Conifer Kingdom

Tsuma Gaki Plant Details

Red fingernails in spring.

If you plant a big tree in a pot, eventually, the roots will displace pretty much all the soil and it will be hard to keep it well watered. Further, much of the nutrient uptake comes from small feeder roots, which will be crowded out as your tree roots fill the pot. If you want a bonsai, you'll need to repot it every 2 to 5 years, depending on what tree it is. If you don't do a good job, the tree will die. If you want an expert, it will cost you.

You really, really want to buy a dwarf tree that is not going to outgrow the pot. Although, frankly, I don't see why you want it in a pot at all. Plant it in the ground.

@gardengal48 (PNW Z8/9) And what are some signs you would look for that the tree needs to be root-pruned and have soil refreshed?

You may find the container needs watering more frequently or that water seems to run out the bottom as soon as you apply. The tree may also not leaf out as fully as it should. But it is always best to root prune and repot before you see any signs of the tree showing stress.