Chinenses section irises

John Lonsdale
Sat, 03 Sep 2005 17:08:56 PDT
Alberto wrote:

"A few comments. Do give your clumps-to-be-divided a drenching with a
systemic insecticide one week  before the actual dividing. Second, do 
not touch the main clump: dig a sideward hole and remove the offsets as the 
roots become visible. Third and so obvious: repot the fans individually and 
move to a place with very good light and no direct sun. I have used pure 
Perlite (no other ingredient) and rooting has been amazingly fast."


Many thanks for your comments.  Do you mean an insecticide drench, or
systemic fungicide?  You don't say whether best in fall or spring - my
divisions that didn't do well were taken in late spring.  I'll increase the
perlite in the pots I pot the fans up in.  They do come fairly easily from
seed (if you catch it) and hopefully next year I'll start to see any
variation in the seedlings.

The neighbors got a treat today - they got to watch me vacuuming the
greenhouses.  With the forced ventilation, even with mesh over the intakes,
a good number of leaves got sucked in over the years, and the dead foliage
that drops off various dormant bulbs, corms and even rhizomes (but not
cormous rhizomes) can build up.  I don't generally get much in the way of
fungal problems but figured it was time to clean up.  The shop vac did the
job, although I'd have preferred the house cleaner but my wife was in.  I
then washed down the glazing and sprayed the whole structure with ZeroTol,
including benches and newly repotted plants.  I'm going to try the latter as
a foliar spray through the winter to keep botrytis at bay during any damp,
dull cold spells, particularly on the cyclamen and western US frits that
emerge early.  I've heard many good things about it and finally put out the
considerable amount of money that 2.5 gallons of concentrate cost.  I think
it will be worth it.  It works as a peroxide but at a tenth the strength of
hydrogen peroxide and without phytotoxicity.

The bulb and cyclamen repot was finally finished today and the first of the
Cyclamen graecum are already in flower, as are more hederifolium in the
garden.  I just have 30 new snowdrops to plant in the garden tomorrow, as
well as about 30 different South African bulbs/corms that Rachel Saunders
sent me as seeds in 2002 that were likely hardy here in SE PA.  They are
flowering size or close enough now so we shall see!  I also have 4 new
Crinums to plant out, after last year's experiments with Cecil Houdyshel and
Mrs. James Hendry proved successful.  The former was beautiful about 3 weeks
ago and adds a touch of something I never knew I was missing.  

Colchicum macrophyllum showed up yesterday in the onco bed but not the front
of the house, the hot and dry weather has pushed the early bulbs back a bit,
which I prefer.  Merendera (Colchicum) montanum is also just popping through
and Leucojum (Acis?) valentinum is undoubtedly hardy, coming back for a
third year outside with 9 strong scapes.  The flowers are over 1" across,
crystalline white and almost flat when fully open, and lovely. 

Enough rambling.



John T Lonsdale PhD
407 Edgewood Drive,
Exton, Pennsylvania 19341, USA

Home: 610 594 9232
Cell: 484 678 9856
Fax: 801 327 1266

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USDA Zone 6b

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