what state are you in? Must be east coast or Arizona (or maybe northern Cal) since we don't get summer rains in southern California. Where you are will factor in on how you plant these plants, since zone 9b is a marginal zone for this species. A bad freeze could kill them all off overnight. If you live in Florida, you might someday get the hedge you wanted with Areca palms (Dypsis lutescens)... may take 6 years to a decade. Would take several decades, if ever, if you live in California. Would only take about 4-5 years in Hawaii, but no zone 9b in Hawaii that I am aware of (maybe a mountain top?). Frankly, there are few palms that make good screens unless you live in a tropical climate, at least in any decent number of years. But most palms grow a lot faster on east coast than west, so if you live there, might have better luck that I would. Rhapis or Chamaerops might be a better choice.

If I were going to be creating a screen with Areca palms, I would be planting them a foot or so apart at the most, and even then would not expect a good visual screen for some 10-20 years. Unless of course you are rich or have a source for dozens of 20 gal areca palms for cheap. Water well and fertilize often, particularly if you live in sandy soil (fertlize with a water based, or a slow release granular, but caution on the amount of slow release since fertilizer burn can be a big problem in palms). What is post planting?

Oops, sorry, I'm a little new to the landscaping stuff (but with 3/4 acre to rehabilitate, I'll be a pro before I'm done) and didn't even notice that 9b exists in several regions.... I'm in west-central Florida, south of Tampa Bay and on the coast (sadly not actually on the water).

I've attached a pic of the areca line between us and the neighbor. The clumps are 6 feet apart and the space between is nearly completely filled (there is one gap-- spacing is over 10' there). I don't need a physical/security barrier (there's a 6' stockade fence taking care of that), so it's really just for sight lines above the fence and to soften the look a bit-- that line of fence is over 100' long.

I think I'm comfortable with ~5 foot spacing, based on the look of the existing line, but you have me worried about growth rates. The existing line has been mature since we bought our house, so I have no idea how fast they might grow. I can't find it now, but I swear somewhere on the UF IFAS site they mentioned a 1-3 foot/year growth rate.

Thanks for the advice, esp on fertilization. Sorry, by "post planting" I mean "after planting." Meaning: are there different starter vs. long-term fertilization and watering regimens.

if you live south of Tampa, that should be a good enough climate to keep these alive for some time.. .and also a good climate to fast growth... you might get these to work out for you. Will definitely need a lot of fertilizer for you sandy soil. STill is going to take years and years... but eventually might be worth it.

There are also a number of different varieties of Golden Canes, some clump more than others, some will only produce a couple of stems. You'll not only need time, but will also have to make the right choices.

I'm not sure what your asking. I see some giant Areca palms in your photo already. Bigger then any California Dypsis lutescens- greener too!.
I don't see why young palms couldn't fill in as fast for you as a privet hedge for us.
You might even try your own native clumping palm-- Paurotis?

stanofh: Those palms in the picture are on the other side of my property. I'd like to duplicate them on the other side as it's a great hedge and arecas are obviously happy here. But since they were planted long before we bought the property I wanted to get some advice.

tropicbreezent: Thanks for the tip. I've had two different nurseries recommended, so I'll be sure to make sure I explain what I'm after.

lzrddr: Good to know about liquid vs. long release. So just get a palm fertilizer and follow the instructions, and I should be good? Will look for signs of over/under fertilizing as I've ready here.

I have a friend who has a line of Arecas planted along her pool for privacy. They were planted 10 years ago in gravel. She has never fertilized them or watered them. The friend is a snowbird who spends 4 months of the year there. Rest of the year, the house is vacant.

These Arecas must be 15ft tall and 10ft wide. She has the gardener cut them back as they keep growing toward the pool and hang over it.

Trust me, these can take neglect and probably thrive on it. I wouldn't worry about water or fertilizer.

Jane