Thanks, Vic. Over fertilizing is one of my
scenarios as to what is happening. As I rework the barrels, I will be more
careful about that. The irises clearly are happy for several years before
declining growth sets in. I believe you are right about the foliage
needing to be above water. I have seen giganticaeruleas in a swamp go
dormant in a long drought. Then, when the water rose again and there was
not the usual foliage, massive numbers did not come back.
Patrick
----- Original Message -----
From:
v*@msn.com
To: i*@yahoogroups.com
Sent: Monday, July 04, 2011 4:57 AM
Subject: RE: [iris-species] Vic -- Iris
virginica --
Patrick,
I don?t understand why the roots of your Louisiana irises
roots do not extent more than six-inches deep in your barrels. My tubs
are approximately 23? x 16½? x 15? deep and when I have emptied tubs, the
roots appear to go all way to the bottom of the tubs. I don?t believe the lack
of oxygen in the soil would limit the growth of the roots. In flooded
soil (non-flowing water), oxygen is usually depleted throughout the soil
profile. Louisiana irises have the ability to transport 02
from the atmosphere through the leaves into the roots, as long as some
parts of the leaves are above the water surface. Keep the leaves completely
flooded for any extended period of time and I believe the irises will
die. It is possible that you are over fertilizing and salt is building
up in the containers.
Vic
From: iris-species@yahoogroups.com
[mailto:iris-species@yahoogroups.com] On Behalf Of Patrick
O'Connor
Sent: Sunday, July 03, 2011 8:16 PM
To:
iris-species@yahoogroups.com
Subject: Re: [iris-species] Vic -- Iris
virginica --
Thanks for your
response. I think my containers may be larger than
yours. Mine are half barrels. I am not sure how many gallons
that translates to, but they are around two feet in diameter and I put about
18 inches of soil in them. When I set them up, they did
great, and the Louisiana rhizomes for some varieties multiplied so well
that it was difficult to pull a rhizome out. Last year I began to rework
some of the barrels in which the plants were not doing as well as
previously. When I dug out the rhizomes I noticed that the roots did not
extend down more than about six inches. It was like a kind of dead zone
down there. My thought was that over time the oxygen below a
certain point was depleted. In shallower containers that may not
happen.
I have fertilied each year
with Osmocote. It seems to work well for several years, and then the
growth in the barrels declines regardless of fertilizer. In a couple of
instances, I have noticed that after a year in this condition (and inadequate
time to rework the barrel), good growth starts again. This has made me
wonder if I over-fertilized. I really don't understand what occurs when
there is no flow of water through soil.
My efforts now are directed
to reworking the barrels on a rotating basis. I take out all the soil
and start again, and the old stuff gets mixed into the
compost.
I would appreciate any
reaction based on your experience.
----- Original Message
-----
Sent: Friday, July 01, 2011 3:48
AM
Subject: RE: [iris-species] Vic -- Iris virginica
--
Patrick,
According to my records, the I. virginica in the photo
were transplanted into no-drainage tubs in April of 2006.
However, I have other I. virginica in my garden growing in no-drainage tubs
for approximately twice as long. I usually fertilize my irises once a
year; occasionally twice a year, except I. tridentata which receives no
fertilizer. And, I have missed fertilizing during a year. I reside in
a high-rainfall area and, I assume, that some flushing out of the tubs
occurs during high -rainfall periods. We also have long dry spells, like the
one we are now just leaving. I have not observed any problems with
salt buildups. The only problem I observe is that over time, very
occasionally, a problem with overcrowding might develop. I also grow lots of
Hymenocallis, Crinums, and other plants in no-drainage tubs.
Vic
From: iris-species@yahoogroups.com
[mailto:iris-species@yahoogroups.com] On Behalf Of Patrick
O'Connor
Sent: Thursday, June 30, 2011 10:30 PM
To:
iris-species@yahoogroups.com
Subject: Re: [iris-species] Vic --
Iris virginica --
Over how long a period have
you grown virginicas in no-drainage tubs? I grow Louisiana irises in
half barrels with no drain holes. I find that they do really well for
several years, then decline in some cases. I have never been certain
how to fertilize in that situation and don't know the extent there is a
build-up of byproducts. Fertilizer recommendations generally assume
that the soil is flushed out over time, but I really don't know what is
going on in those barrels.
I would be interested to
know your thoughts and those of others.
----- Original Message
-----
Sent: Thursday, June 30, 2011 7:19
PM
Subject:
[iris-species] Vic -- Iris virginica -- Emailing:
CIMG0692.JPG
Mark,
Your recent email asked if Iris virginica would grow okay
in no-drainage
tubs. The attached photo taken 6/29/11 shows I.
virginica growing in
no-drainage tubs in my garden. They appear happy
to
me.
Vic
CIMG0692.JPG:
|
