Planting in fall...

[Breaktheory]

Any thoughts on planting in fall or even early winter....I’m in LA although a part w extreme temps - I’m looking to plant in September or October when temps will likely be high 70s to mid 80s

[Merlyn]

As a general rule of thumb, I don't plant "vulnerable" plants any later than November here in central Floriduh.  So, for example, I am in borderline 9b/9a.  Typically I get 1 or 2 nights in the upper 20s, and rarely a dip to about 25F.  I would have no problem planting a Butia in November or pretty much any time of the year, since they are hardy into the upper teens.  The risk of damage in a "typical" winter is pretty low.  But I wouldn't plant an Areca Triandra, which is not particularly hardy below 30F.  I'd plant something like that in the spring or summer, but not past around mid-October.

[Breaktheory]

So assuming we have a mild winter, there wouldn’t be any reason to think the palm wouldn’t thrive as well as a spring plant?

[Dusty CBAD]

So far I only plant in the spring, but that’s mostly because I try to give myself a break from this hobby and I don’t feel the need to rush. Winter is for surfing. I know for sure spring is good so I don’t bother with winter. But there’s lots of older posts from very experienced members in so cal that say they plant all year long.

I think it’s palm dependent. I don’t think planting a bottle palm, bentinkia condapanna, or clinostigma is probably a good idea in winter (these are just examples of marginals). I think I’d stay away from planting a royal in the winter too. But I think most of the new cal stuff and the hardier dypsis are probably fine. 
 

The time frame you gave for planting is right around our Santa Ana time. I’d be more worried about planting a palm in more sun than it’s used to since most palms in pots are grown in at least a little bit of shade or even worse, straight from a greenhouse (just the nature of growing large amounts of palms at nurseries). Then it will burn. Then let’s say we have a gnarly multi-day Santa Ana event. Now your palm looks like shit for a year or two, or can’t recover and now a colder than normal winter takes it out.

Just something to think about. Again, a lot of experienced palm growers plant year round, but I bet they’d tell you the same thing about palm specific. 
 

good luck,

Dustin