Once upon a time on usenet David E. Ross wrote:
On 3/22/2015 3:55 PM, Boron Elgar wrote:
On Mon, 23 Mar 2015 09:21:04 +1100, "David Hare-Scott"
wrote:

Boron Elgar wrote:
On Sun, 22 Mar 2015 18:27:37 +1100, "David Hare-Scott"

One can have citrus come back from scale and almost total leaf
loss. It can happen.

Boron

Sure you can, never suggested you can't. The more stresses you put
on the plant the less chance it will reach anything like its
potential and the more chance that one more stress will be its last.

If one is growing potted citrus, the "potential" is not anywhere near
to that of yard-planted however. Lowered expectations, shall we say.



Dwarf citrus in a very large pot will reach its potential. My dwarf
kumquat is covered with ripe fruit. By the time I finished eating the
2013 crop, the 2014 crop was already ripe. My dwarf 'Eureka' lemon
has more than 3 dozen ripe lemons, most as large as any I see in the
supermarket. This lemon tree also has flowers, baby lemons and
maturing green lemons. Both the lemon and kumquat are in flower pots
that are 22 inches across at the top and 20 inches deep.
Fortunately, citrus fruit remains fresh on the trees for several
months after ripening.

A note about 'Eureka' lemons: Unlike most fruits, 'Eureka' lemons
have no season. They are everbearing. You should expect to find
flowers on and off year round. At the same time, you should also
expect to find small and large green lemons and ripe lemons at the
same time. If a lemon tree loses all its leaves, that will severely
impact its fruiting ability.

I've only recently started replacing my non-dwarf citrus trees with citrus
grafted onto dwarfing Flying Dragon rootstock. I have pots that are 20"
diameter and 18" tall, slightly tapered at the base. I still have two
full-size trees in these containers and some small self-grafted ones growing
on. I grow in containers as, sadly I find that, at the stage of my life I'd
planned to be in my own home starting a small orchard I'm in rental
accomodation. It's hard to plan around a catestrophic back injury. :-/

I gave up on trying to keep full-size trees pruned hard so they'd thrive in
these containers. The two I still have are a Meyer lemon - it too fruits all
year around and isn't a true lemon rather a lemon crossed with either a
mandarin or an orange. It's flavour is more subtle and complex than any true
lemon, there's a high-end cake shop in my local town and the chef there
can't get enough Meyers. Every so often I'd drop in with half-a-dozen fruits
and he'd trade me for a box of cakes and pastries. Because it fruits all
year round it's not grown commercially - commercial growers like a picking
season and an off-season.

It's always had some scale insect on it (I don't like using strong chemicals
on food plants, especially with this having ripe fruit on all year). However
two years ago the infestation got particularly bad and the trees was getting
too big for the pot anyway so I took drastic steps... I picked all but one
of the ripe fruit (67 to be precise), pruned it heavilly, unpotted it and
root-pruned it back to 50% size root ball, making six radial cuts through
the root ball almost to the centre and teasing the old soil out.

I put it back in the same pot with new soil. A few weeks later when there
was new growth on it I removed all of the old, scaley leaves. It was back to
its old self within a year, however I've kept it cut back and have been
removing about 60% of the fruit as it's days in a pot are numbered. (When my
grafted dwarf tress come in I'll need the pot for one of those.)
Consequently the fruit that are on it are huge - I just measured one and
it's 11.5" in circumference and nearly 6" long! I've also top-worked it as I
don't use all of the fruit as it is and so the centre branches are now Moro
blood orange. I'm going to leave some Meyer lower branches though.

The other full size tree in the same size pot is a Navellina. Last winter I
got 52 large sweet and juicy fruit from it but because it'd grown so big it
needed tying to the railings around the deck to stop the pot falling over
when it gets windy I pruned it hard after fruiting. Because of that there's
only 15 half-grown fruit on it now and I'm constantly removing new growth
(other than encouraging a leader as I'll want it taller when it goes in the
ground).

While I agree with Boron's comment "These aren't puppies...they are plants"
I'm quite attached to my trees. So much so that instead of just buying dwarf
citrus to replace them I got my hands on some Flying Dragon dwarfing
rootstock and have been bud-grafting my old trees onto new roots. It's
worked out to be the more expensive option as I had major problems getting
my hands on the rootstock, then had to pay as much for it as I'd pay for a
two year grafted tree. (Nurseries don't want gardeners grafting their own
and not buying their products.) I'm sentimental and this way I sort of get
to keep my 'old' trees but won't have to keep fighting against them to keep
them small.

Back to the scale insect issue though... I've recently been using Neem oil
and while it's too soon to say that it's a complete success I do have far
less scale insects than I used to. I really don't want to just blitz the
insect population of my trees as each one is like a mini ecosystem. Yes
there are a few aphids but there are also ladybugs. There are a few whitefly
but the trees also act as nurseries for young jumping spiders who feed on
the whitefly.

I think that for long term success we can't simply remove one component of
an ecosystem (the fruit tree) and grow it in isolation. It's not good for
the tree, the planet or us. The secret is not letting any one 'pest' get to
the stage where it threatens the tree's health.
--
Shaun.

"Humans will have advanced a long, long, way when religious belief has a
cozy little classification in the DSM."
David Melville (in r.a.s.f1)