From: br105@cleveland.Freenet.Edu (Jeffrey A. Del Col)
Subject: Re: Roses:Fungus control
Date: 13 Jul 1993 11:53:03 GMT

In a previous article, Barry_Carlson@mindlink.bc.ca (Barry Carlson) says:

> I am growing my roses without using any pesticides or herbicides and
> I would very much like to hear from other people who are trying the
> same approach.  I would particularly like to know what methods you
> use for controlling the fungal stuff- black spot and powdery mildew
> in particular, and how effective you feel these methods have been.
> Have you tried garlic?  horsetail?  baking powder? How important is
> just "biting the bullet" and only growing resistant varieties to
> your way of thinking?  What cultural practices to you think are
> important?  The majority of the rose books are absolutely awash in
> chemical sprays and I know there must be other answers and other
> experimenters out there.  Thanks for your help.  -Moira Carlson

Garlic?? Never heard of that technique.

Anyway, to treat fungal infections without resorting to polysyllabic
megadeath mixtures, the tried and true approach is to use lime/sulfur
dust or spray. You garden will smell like Hell's waiting room for a
couple of days, but the stuff does work.  Don't try it on rugosas;
their leaves seem sensitive to almost any spray, but then rugosas are
pretty resistant to fungal attack anyway--at least mine are.

Lime/sulfur dust is widely available.  Orthrix is a proprietary
lime/sulfur liquid concentrate.
===

From: J.VanZijll@massey.ac.nz (J van Zijll de Jong)
Date: Tue, 13 Jul 1993 22:17:02 GMT

I have heard of baking soda being used for powdery mildew, but don't
know how effective this is.
===

From: dm055@cleveland.Freenet.Edu (Rebecca A. Jone)
Date: 14 Jul 1993 04:08:42 GMT

The white powdery stuff is mildew.  The rust colored stuff is --
rust.  Both are fungi.  You can spray with Funginex to help control
the fungi.  You can also use Orthenex which contains Funginex along
with some insecticides that are useful with other rose problems such
as thrips, aphids, and spider mites.  Either should really be used on
a regular basis (I spray once a week) to prevent a serious outbreak of
mildew or rust or blackspot (another popular rose fungi).
===

From: jhb@cvsd.cv.com (Jim Bishop)
Subject: Re: Roses: Problems on leaves  (help)
Date: 16 Jul 93 06:15:20 GMT

rutten@kits.sfu.ca Jacqueline Maria Rutten writes:
>> Also, small 'rust' spots have developed on leaves that do not have
>> the 'dust' on them.  On the under side of the leaves, there is a 
>> VERY tiny fuzzy, bright orange spot that is more spherical than 
>> flat.  Fungus??? Pest???  OTHER????????  Is it curable and how?????

klier@iscsvax.uni.edu writes:
> One of the leaf rusts, also a fungus.  Fungicides again.  Actually,
> neither powdery mildew or rust is a real rose-killer for most
> cultivars, though they can make the plants kinda ugly...  I prefer
> to plant rust-, mildew-, and blackspot- resistant roses and let them
> duke it out with the fungi without my intervention...

Yes, disease resistant roses are the way to go.

I heard the following about rust years ago.  I can't verify it, but it
seems to work for me.  Rust is spread from the soil below the roses.
Hence splashing water on the lower leaves can start the spread of rust
up the plant.  Also, annually removing all the leaves from roses,
including the dead ones below the plant, is very important it
preventing the return of rust from year to year.

I tend to believe this, since I rarely get rust on the roses that are
watered by drip irrigation.  I've also noticed that rust always seem
to start from the bottom of the plant and work its way up.

Jim