hort.net Seasonal photo, (c) 2006 Christopher P. Lindsey, All Rights Reserved: do not copy
articles | gallery of plants | blog | tech blog | plant profiles | patents | mailing lists | top stories | links | shorturl service | tom clothier's archive0
Gallery of Plants
Tech Blog
Plant Profiles
Mailing Lists
    Search ALL lists
    Search help
    Subscription info
Top Stories
sHORTurl service
Tom Clothier's Archive
 Top Stories
New Trillium species discovered

Disease could hit Britain's trees hard

Ten of the best snowdrop cultivars

Plant protein database helps identify plant gene functions

Dendroclimatologists record history through trees

Potato beetle could be thwarted through gene manipulation

Hawaii expands coffee farm quarantine

Study explains flower petal loss

RSS story archive

Re: Strange spots on leaves

Guess it's about time for me to put my 2 cents worth in here on this topic.
 I have found that during periods of heavy rain that spores which live
normally in the soil are splashed up onto the leaves and germinate (?)
sporulate (?) resulting in the brownish spots.  The causitive agent is
described in "Garden Irises", on page 106, as Heterosporium Leaf Spot (H.
gracile).  The same problem is described in "World of Irises", on page 340,
under the heading Fungal Leaf Spot.
While the spot tends to detract from the overall appearance of the clump, IT
IS NOT FATAL, and will disappear as soon as the weather changes to dry.  You
can spray anti-fungals but you would be better served to save your money.
 There are no iris that I know of that are totally immune to leaf spot but if
you search your garden you will find many iris that are less susceptible.

P.S. There is a picture of leaf spot on page 105 of "Garden Irises"

 Regards from Dave Silverberg where leaf spot is a way of life in the wet
Pacific Northwest.  But it all disappears when the weather dries up from June
15 to late October.

 © 1995-2017 Mallorn Computing, Inc.All Rights Reserved.
Our Privacy Statement
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index