Mediterranean climate (was Fritillaria raddeana)

Lee Poulsen
Sat, 15 Sep 2012 13:22:31 PDT
Adding onto what Mike said, I've come to think that, as far as bulb growing goes, any region that has what I think of as a 'smile' shaped annual average rainfall pattern can be considered to be "mediterranean".
(I hope this shows up correctly after being mailed. If it looks weird, then change the font to a monospaced font such as Courier.)

++++                            ++++
    +++                      +++
       ++                  ++
         +                +
          ++            ++
            +++      +++
 J  F  M  A  M  J  J  A  S  O  N  D     (N. Hemisphere)
 J  A  S  O  N  D  J  F  M  A  M  J     (S. Hemisphere)

It doesn't seem to be as important how rainy the winter rain amount is or how dry the summer dry period is, as long as there is a marked difference between the two. Also that the warmest temperature period is also the least rainy and the rainiest period is also the coolest period.

Now some species really do want pretty much zero moisture during the hottest period of the year, but usually because they come from mediterranean regions that really have pretty much no rainfall ever during the hottest month, year after year after year. From what I've seen of worldwide temperature records, this appears to only occur in Chile and California. Other species seem to want their roots to have a little soil moisture throughout the summer and those generally speaking seem to come from regions that get at least 3 or more cm of rain per month on average during the summertime. But remember these are only generalities. In any case, as Mike mentioned, the 'stan countries seem to have a lopsided smile pattern and you find some bulbs from there that act or can be treated as mediterranean. Iran and parts of Turkey are confusing to me because as you get closer and closer to the Black and Caspian Seas, the average annual rainfall pattern becomes decidedly not-smiley. Species that come from those areas don't seem to do as well for me here in southern California as those from the south side of Turkey, for example.

--Lee Poulsen
Pasadena, California, USA - USDA Zone 10a
Latitude 34°N, Altitude 1150 ft/350 m

On Sep 15, 2012, at 11:27 AM, Michael Mace wrote:

> Randy wrote:
>>> Most of Iran falls in the typical "Mediterranean climate" type, which
> extends very far inland in the eastern Mediterranean region than it does
> elsewhere in the world. 
> One of my favorite topics.  The concept of a "mediterranean" climate is easy
> to understand (dry summers), but when you get into the details of its
> official definition, things get confusing.  Even if an area has winter rain
> and summer dryness, if it gets too little total rain per year, it may be
> classified as "desert" rather than mediterranean.  And if it gets too cold
> in winter, it may be classified as "continental" or "steppe."  The official
> definition of mediterranean also allows a fair amount of summer rain (which
> is why some "mediterranean" bulbs can naturalize in lawns and other places
> that get watered in summer).
> I won't get into the details, but you can drag yourself through the articles
> on Wikipedia if you're having trouble getting to sleep some evening.
> As a result of the classification weirdness, the places that grow some of
> our favorite summer-dormant bulbs are not technically classified as
> mediterranean.  Those areas include the Sierra Nevada mountains in
> California (too cold), Nieuwodtville in South Africa (too dry), everything
> north of about La Ligua in Chile (too dry), and as Randy mentioned, most of
> Turkey and a huge chunk of Iran, the "stans" and other parts of the Mideast
> (too cold and/or dry).
> The lesson out of this is not to get too hung up on the official definition
> of mediterranean.  It was written for climatology, not gardeners, and
> definitely not for bulb growers.  And if someone tells you a bulb is
> "mediterranean," don't assume you know how to grow it.  Ask for details on
> how much winter cold and summer rain it expects.

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