Parallel regions

Kenneth Hixson khixson@nu-world.com
Fri, 20 Nov 2009 13:46:33 PST
Rodger wrote:

> It strikes me that a deeper, and possibly more interesting, question is the 
> identification of hardiness indicator plants. A good start on this issue would 
> involve those interested listing plants that don't quite make it, rather than 
> those that do survive.
> 
> Also, let's define hardiness more broadly than just frost-hardy. For example, 
> in my former marsh, a great many Japanese plants are not hardy because they 
> cannot handle the wintertime sogginess. There is an obverse to this, plants 
> that demand summer water to survive.

	In addition, plants that may grow in, for instance, the Pontic region 
of Turkey, may include plants from sea level, and plants from alpine 
peaks.  They are not equally hardy.  Some may grow submerged
in water from snowmelt, and be completely dry and dormant a month later.
Trying to grow them in standing water here would be foolish.
There are numerous instances of plants that survive under a snow cover
that not only insulates and protects the ground from freezing, but also
keeps plants from being wet while cold.  Such plants moved to a milder
climate that doesn't keep them dry in winter, fail at warmer
temperatures than they withstand in their native area.  One example from
this area would be Lewisia--they can take cold, they can't take cold and
wet--or, often, warm and wet.  Lewisia rediviva can die under either
condition, but will tolerate something like minus 30F if kept dry when
dormant.
	I'm not sure this really comes under the heading of "hardiness"
but perhaps something like "growability"?  Apricot trees are another
example.  Adapted to a continental climate, they can withstand severe
winter cold.  Yet in my mild winter area, they start to grow when the
weather first starts to warm, then can be killed in a later frost much
less than they withstood in the middle of winter.  Gladiolus
callianthus/ Acidanthera are hardy here, but they only start to grow
after the soil warms, so do not grow long enough to flower.  Potted and
taken inside in the winter/early spring, they grow long enough to flower.

> Teucrium fruticans is another indicator. It thrived for years, but last winter 
> put paid to it, even though we only had a couple of nights of seriously cold 
> weather.
	I gave up on Teucrium, the three or so species I tried seemed hardy,
but they couldn't take winter wet--and/or winter wet and cold?  They
survived, but looked so bad I finally gave up on them.


Jim Shields wrote:	>Crinum bulbispermum, variabile

	I admit to not being sure if you mean Crinum variabile may be hardy for
you, or Crinum bulbispermum is variable in hardiness depending
on location.  Crinum bulbispermum grows well here, but is somewhat
variable in performance--in summer 2008, some of them reflowered three
times and were starting a fourth in September when the days started
cooling and shortening noticeably.  In summer 2009, flowering started
almost a month later, and there was only one--fairly long six week or
more flowering, with no rebloom.  I didn't deadhead, so seed set may
have reduced rebloom.  'Burgundy', which started in late July in
2008, didn't flower at all in 2009.  Amaryllis belladonna didn't flower 
either, though leaf tips are coming up now the fall rains have started.

Ken






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