Re: Soil pH

Chris,
 
The only report of *increase* in SA trait _expression_ with more acidic conditions was Bill Burleson's experiment with MESMERIZER.  Ordinarily, SA _expression_ seems to increase with higher pH.  Bearded irises are native in mildly alkaline to neutral (7) pH, and perform very well at 7.5.
 
Soil tilth and fertility--available micronutrients--are especially important.  There's quite a shift in profile of what micronutrients become soluble or available moving from 6.5 (mildly acidic) to 7.5 (mildly alkaline).  Bearded irises generally thrive best in warm, dry mildly alkaline conditions where moisture is available seasonally.
 
This isn't universally true--but one might note the distribution of *I. aphylla* for example.  In Poland it is reported found in "xerophytic" grassland areas.  I assume "xerophytic" is relative--Poland generally being in a climate zone that receives ample summer moisture.
 
None of the bearded iris sites of origination resemble your area at all, something that is also true for my climate and soil.  Colleen is in an area that one might describe as "Iris Heaven" if she is located where I think she is.  Her conditions resemble those of the southern half of California to a high degree, I believe.
 
I am amazed you have the success you do with them at all.  I would expect spurias and siberian iris to be more adapted to the climates in Quebec.
 
Neil Mogensen  z 7  western NC mountains

Yahoo! Groups Sponsor
ADVERTISEMENT
click here

Yahoo! Groups Links
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index