I don't recall ever hearing. I bet landscapers don't stress this!
>> thick and fairly tall ... I need a good, tropical -looking screen quickly.
I think F. rufa would do well for you, if your variety in your climate acts the same way mine did. When I said "a few inches per year of spread" I meant the diameter of the
soil patch from which culms emerge. It is a very slow-spreading "clumper" in my poor soil.
HOWEVER, its "droop" means that
the diameter that is screened by foliage is something like 1/2 of the culm heights, and each year they come in MUCH longer for me. I would say that the new erect culms have been 8-18 inches taller than the previous years bowed-over height. I'm not sure what that works out to in width-per-year, but my 2-year plant sprawled around 5 feet wide.
I don't have a photo of my three-year plant in the fall after new culms "sprawled", but I have a photo of it 4.5 years old, pre-new-growth, that suggests
my 3-year plant must have been around 8 feet wide . At that point, I stopped watering it and fertilizing it, And started pruning it back from the sidewalk.
>> 10' on center, estimating full coverage in approximately 3 years.
Hmmm, that means each plant had to sprawl to a diameter of 10 feet? I THINK that my 3-year plant was around 2 feet short of that goal. But my soil stunk! Very low organic content and thin mulch. And I put it in a raised bed that dries out too fast around the edges, so in effect it was only intermittently watered. And now that I know it prefers shade, I might be giving it too much sun , which is NOT something a coastal PNW gardener says very often!
I bought it as a
tiny clump in July 2009, from Home Depot, in a
2-3 quart pot. It wasn't MUCH bigger the second year, perhaps it "only" doubled or tripled the size of its foliage. And July might have on the late edge for planting it out. If you start with bigger, more expensive plants and give them better soil, yours may take off faster than mine.
I guess you don’t want to wait an extra 3-4 years to screen your neighbor’s trash completely. But you could buy fewer clumps and divide each 3-4 ways after 2-3 years. Replant 1 or 2 or 3 clumps between each original clump. And then you would have a uniform hedge, instead of 18 umbrellas in a row.
>> Arundo donax
A runner? You are a naughty person!
There is a PNW Chapter of the ABS:
pnwbamboo.org
This is 4 years old but BEFORE it's Year Four growth spurt. So this is how wide it must have been late in Year Three, after drooping.
