Re: coming out/Tender Succulents Outdoors

Hello Paul,

I don't mean to sound like an authority on growing
tender succulents and subtropicals in your area, but
there are a few tricks of the trade that work very
well here for getting plants through the winter and
wet.  The key thing is probably keeping plants dry
enough so they don't rot.  (I have a similar problem
with keeping many of my hybrid echeverias happy in
winter)  Some practices that work well here in
northern California:

1. Covering winter drought lovers with temporary
overhead cover to shed the rain away, growing in
containers plunged into the ground in summer and
relocated to covered areas in winter, or planting in
raised sloped beds with very quick draining soil mix
and full sun
2. Planting these plants at the base of evergreens
such as Cupressus macrocarpa,(or similar), and limbing
up branches so that things get sun from lower angles
in early morning or late afternoon.  The density of
the tree's foliage tends to keep the area below much
drier, protected from frosts, and the tree roots dry
out the soil more efficiently than even the best
system of underdrains.
3. Using impervious sheets of plastic covered with
light colored reflective gravel around base of
succulents to keep drier in winter, and increase soil
temperatures in summer.  (The look of decomposed
granite as a garden wide mulch is very much part of
the look of the Sonoran desert habitat.)
4. Stringing Christmas tree lights(or similar) around
cold sensitive plants and tenting with agricultural
row cover fabric during bouts of cold weather.  I use
this method successfully with some tender large
Euphorbias, such as E. ingens here, along with
covering the surrounding soil to keep drier.  This
approach is also used every winter on a more
substantial basis at the Ruth Bancroft Garden in
Walnut Creek, where Ruth has amassed a national
collection of Agaves, Aloes and other tender
succulents which are not possible to keep alive in
this area without protecting them.

Lest you think that northern California is so easy for
succulents compared to your area, we need to take some
of the same protective measures here for the plants
only marginally hardy.  My 4 foot tall Euphorbia
tirucallii 'Sticks on Fire' is a good example, as even
under cover of a glass overhang and nestled up against
a stucco wall which reradiates heat, the branch tips
slowly rot and drop off, and I slowly lose about 1/4
of the branch density every winter, until it warms up
again in spring.(This plant would have rotted long ago
if left outside in the rains).  It just isn't as warm
as this plant would like in winter here, and I suspect
it is the temps below 5C which start the process.

Subtropicals like Trevesia palmata also essentially
stop growth here in my garden in the winter, whereas
they are in active growth in Los Angeles all year
round.  My plant is lucky to put on 6 inches of trunk
in a year, as opposed to maybe 3x that down south.  We
can't leave things like Pachypodium lamerei out in the
winter rains either, it will rot.  So there will
always be an element of wanting to grow things just
beyond the hardiness of our area, regardless of where
we garden.

I thought that there was at least one coastal garden
there in the southwest of England with a superb
collection of succulents, on one of the off
shore(Isles of Scilly?) islands?  I never got there,
but it sounds very much like coastal northern
California for climate.  I did notice that many of the
things I would have thought to be hardy in London are
only grown inside in the temperate house at Kew, which
felt very much like a California garden in some
respects.

Best of luck with the ongoing experiment with
succulents in your area,
David Feix


-

__________________________________________________
Do You Yahoo!?
Get email at your own domain with Yahoo! Mail. 
http://personal.mail.yahoo.com/?.refer=text
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index