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Emery Davis[_2_] · 11-05-2009, 07:58 AM posted to uk.rec.gardening

dina wrote:
'Spider[_2_ Wrote:
;843710']"Emery Davis" wrote in message
...-
dina wrote:-
Hi there,
do these fungus only atack roses or other plants as well? Or they are
different fungus alltogether? Can they be treated he same way?
Some advise,please.
Thank you.
Dina

-
Hi Dina,

At least some leaf black spot is caused by the Entosporium fungus.
Which
attacks roses, apples, pears, pyracantha, photinia and vitis notably.

An effective treatment is myclobutanil, also spray Bordeaux mixture
in fall and spring.

HTH

-E-

I concur. There are many other plant types that suffer,though, many
with
their own specific fungi. I can't say I know the name of them all, but
I see
black spotting on Anemones, Hebes, Hellebores, Aquilegia, Penstemon and

others. Rust is another common fungal problem, which affects roses,
hypericum et al. Unsurprisingly, it has rust-coloured pustules, so is

fairly easy to identify, at least in the early stages - later, it can
become
blackened.

I am still trialling the acid feed trick with rust and some forms of
blackspot. I can't say more than that I'm very hopeful. By all means,

follow Emery's advice for treatment. It is a good idea, though, to
change
your chosen fungicide periodically so that the problem pathogen does
not
become hardened to it, and thus survive. Also practice good garden
hygiene,
by clearing up fallen leaves. These will carry fungal spores which
will
reinfect your plant through wind dispersal or rain/water splash. With
a
serious infesation, it may be worth mulching the ground, so the spores
can't
reach the plant again. Similarly, if you spray a wall-trained plant,
spray
the wall thoroughly as well.

Spider

Hi,
thank you for your advise.
I receantly read something which has confirmed what I suspected about
Black spots. They like ph close to neutral and thats why your acid feed
is working as well as combination of water and skimed milk or
bicarbonated soda sprays. They change pH which black spots and mildew
don't like.
I will deffinitly try acid feed as well. I don't like chemicals and
prefere organic gardening if possible.

Dina, do note that Spider said "some forms of blackspot..." My soil is
quite acidic (5 everywhere, closer to 4.5 some places) and I suffer
from scads of the stuff. So I wonder about your statement.

Re Bordeaux Mixture, isn't it OK for organic gardening?

-E