On 16/05/2012 20:10, Frank wrote:
I've always thought that alpines were fairly drought resistant. I have 4
of these growing in a container, in a 50/60 mixture of sand and
uni-compost. But despite being exposed to rain, I've noticed after a few
dry days that a couple of them begin to wilt notably a Helianthemum and
a Mazus Rwptans. The other 2 alpines are unaffected. I've watered since
and the 2 wilted plants soon perked up. But I'm surprised they wilted so
easily.

Many alpines appear to grow in dry areas, simply because it looks dry.
Even if you take those growing in scree - which may be several or even
tens of cm deep , it's what's beneath that scree which is important.
The soil may be quite damp from continuous snowmelt from above, thus
keeping the plant well-watered.

It's quite strange, but dryness at the roots and extreme cold in winter
are two things which alpines often can't tolerate. In the latter case
they are often protected by a couple of metres of insulating snow
throughout the coldest time of the year. That also protects them from
the very dry dehydrating winds at altitude, of course.

--

Jeff