Jonno wrote:

"0tterbot" wrote in message
...
"Trish Brown" wrote in message
...
I have three young casuarinas near my fence line. I'm thinking of
adding more garden beds along there, but that would entail piling
about 40cm more soil on top of the casuarina roots to build up the
beds. My husband reckons this will kill them. Since the trees are now
about fifteen feet tall and doing well, I'd rather not do that. But I
want my garden beds too!

Any ideas? Solutions? Comments?

my first thought is that if they're the kind of casuarina that grow
incredibly tall, always look awful, drop seeds everywhere for people
to skid on & break their necks, drop needles constantly & defend their
root zone, what on earth do you want 3 of them in your yard for,
anyway? g

my second thought is that the trees are far more likely to ruin the
beds than the beds are to ruin the casuarinas. unless (or indeed, even
if) the entire root zone is buried, i imagine it's not a problem for
the vast majority of established trees. if most of the root zone would
be covered, think twice. to keep roots out of raised beds you probably
want a proper barrier at ground level.

mainly, i wouldn't do it because i can't see it working, with one
thing & another - if you can't choose between the trees & the beds,
nature will probably do it for you. although, you've probably gathered
that i don't think casuarinas are a good idea for backyard trees
anyway. (i'd chop them down now while they're still small ;-)

having said all that, i read recently (and i can't remember where!)
that longstem planting is surprisingly effective for more trees than
you would think, & i imagine being water-loving river trees that
casuarinas would adapt perfectly well to finding themselves buried
more deeply than usual - they would most likely just begin sending
roots out from higher up. an example of a tree that will never prosper
buried deeper, are those with grafts. a hardy native tree should be
ok. but as i said, i'm not convinced the beds would prosper. they
might be ok, though. if the beds are for a few sturdy perennials,
perhaps no problem. if they're for veg, i'd say do it elsewhere & give
the veg a better chance.
kylie
Why not gamble and find out.
My gut feling is that it wouldn't hurt them one little bit, as the roots
would compensate by growing into the garden beds.
Despite what is said, plants aren't suicidal, and can adept.

Thanks for the intelligent discussion! I'm going to take the gamble and
see what happens. I only wanted to grow a few annuals in the beds, just
for flowers indoors. Oh, and some dear old geraniums against the ugly fence.

Kylie, I hear what you say about not liking casuarinas, but I do! The
sound the wind makes as it blows through their needles is so relaxing.
The sound made by cockies as they gobble up the nuts isn't quite so
relaxing, but I like it anyway. And if they drop their needles, oh well.
Thing is, my husband (*not* a gardener) fell in love with these trees
and bought the three on special. They're 'his' contribution to the
garden, so - y'know - I hope they survive. I'll let you know whichever
way. All in the course of furthering the collective knowledge, eh? ;-D

--
Trish Brown {|:-}

Newcastle, NSW, Australia