Howdy,
In regards to this message
|
| I have a purple wisteria that I planted next to a
dead
| tree in my front yard last Spring - I'm planning
to
| train it up the trunk. It gets full sun all day
| (pruned all the big branches off the tree), and it
did
| spectacularly well last year. It even bloomed in
| April! I pruned it in September and now it seems
very
| unhappy. The new leaves that have come in since
| pruning are light green and now are starting to
turn
| brown. I gave it some ironite, thinking the light
| green leaves were indicating an iron deficiency --
the
| soil in our front yard is nice and organic down to
| about 8-10 inches, when it turns to caliche, but I
| didn't think this was a huge problem for Wisteria.
| I'm wondering if it's just in the process of
losing
| it's leaves for the winter and I'm worrying for
| nothing. Should I mulch it for the winter?
Fertilize?
| If so, with what? Help!!

The Wisterias are losing their leaves due to the cold, they are
deciduous, mine sheds it's leaves in November quickly, and is about
hald defoliated.
As far as the light green leaves, a couple of things may be at
work. Since it was pruned in September it was encouraged to put on
new growth at a time when it normally would not be doing so, and the
plant may not have the impetus to create more chlorophyl than it needs
heading into it's dormancy period.
In addition the rainy period we just finished up with may have
left more moisture in the soil than the plant could handle. The plant
discharges the excess water to the leaves and then sheds them as a way
of coping with the stress. In this situation the leaves turn yellow
uniformly.
Iron defieciency is very distinct in leaf coloration. Yellow
leaves but clearly defined dark green veins.
Since the plant is going dormant this is not a good time to
fertilize anyway ( Sort of like letting my teenager drink coke before
bedtime, one needs their rest )
If there was an iron defiecency I would not use Ironite. The '
secret formulation process', a proprietary secret that the producer
and the EPA believe you are better not knowing, puts it outside the
range of anything I would want in my landscape. The creator of this
product has a habit of sueing anyone who reveals what the complete
chemical analysis of this product is, which the EPA does not require
listed on the box ( Unlike food labels, fertilizers are not required
to have full disclosure )
You can find out all about this by reading Duff Wilson's book
"Fateful Harvest" ( Seattle times reporter, and Pulitzer runner-up )
What makes the Iron thing tricky is that very often in Austin
soils there is sufficient Iron but the PH of the soil is out of whack
making the plant unable to take up the Iron, giving symptoms of
chlorosis. ( Travis County Extension ) Adding more Iron may in fact
excaerbate the problem. In general it's worth getting a soil test
before the major addition of any soil additives aside from compost.
A good source of Iron is granite sand, which I was introduced to by
the head gardener at East Side Cafe who uses it extensively.
There is also a seaweed plus Iron mix that I have never used so can
not vouch for.

Hope this was of some help,
take care,
Steve Coyle
www.austingardencenter.com