fungi

**Monarch mastiff@swbell.net>**

"Mary C. Weaver" wrote:
> No. The healthier the rose, the better it will do, although the vast
> majority of roses will have problems with blackspot or powdery mildew
> if environmental conditions are right. Blackspot is predominant in
> climates with lots of rainfall because the spores can't germinate
> unless the foliage remains wet (note: humidity has nothing to do with
> it) for at least 7 continuous hours. 

I hate to be disagreeable but here in south Texas rainfall has nothing
to do with getting black spot on the roses here.  We had no rain for 104
days straight from mid June to September.  Many days the humidity would
knock you down, I still had black spot.

Hence the warnings about not
> watering from above and not watering late in the day. Powdery mildew,
> on the other hand, is discouraged by the presence of water on leaves
> and tends to be more of a problem in dryer climates.

I get mildew on some of my roses, much less of a problem actually than
Black Spot.  The mildew comes when the days are warm and the nights
cool.
Once summer gets here and our nights are in the 80-90's, the mildew
disappears.  I learned to 'bathe' my roses when I water them, hitting
them with a hard jet to knock off the bad leaves.  This has been the
best solution I have found and had much less problems after I started
bathing than I did before.

> How do you encourage health? Plant the roses in good soil with plenty
> of organic matter. Make sure they have plenty of sun--most prefer at
> least six hours a day--and are not shaded in the morning (in order to
> avoid blackspot, you want the dew to be dried by the sun). Give them
> plenty of water and adequate fertilizer. Buy healthy plants in the
> first place. Maintain good hygiene in the flower beds, raking up
> diseased fallen leaves.

I think a lot has to do with the disease resistance of the plants to
begin with since some of mine planted in deep shade under a tree or on
the west side of something don't get fungi no matter what happens. (Cl.
Cecile Brunner, Cl. Old Blush) Others in full sun from sunrise to
sundown still get it.  I agree that the healthier the plant the better
it is able to ward off evil spirits.

I refuse to rake fallen leaves, way to much trouble for as many roses as
I have here (150+).  Hard to do anyway without loosing the mulch.  Plus
I use roses as perennials in a flower bed rather than adding perennials
to the rose bed.  Most of my roses are under planted with salvia,
artemesia, or something else so raking is nearly impossible without
destroying something else.  Actually I think the under planting has
helped the roses by keeping the fungi spores from being blown around as
much and the leaves compost faster.

> I recently wrote an article for hgtv.com on a dozen easy-care roses.
> If people are interested, I'll post the link when the article goes up.

Yes, please do!

This year will be the year of the shovel!!  I need roses who can take
the extremes of weather and fend for themselves.  Unfortunately it's to
hot here for Rugosa's, all I have tried have croaked in the heat.  The
China's do very well here thank goodness.

Linda
south of San Antonio, TX
zone 9 depending on the year

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