I was wondering whether any URGlers have experience of keeping cacti in a
polytunnel?

Any info regarding ventilation, heating in winter etc would be good.
--
Jenny
(Rotterdam the Netherlands)
remove the squirrel to reply

JennyC wrote:

I was wondering whether any URGlers have experience of keeping cacti in a
polytunnel?

Any info regarding ventilation, heating in winter etc would be good.

Which species? If you can keep them dry and above 5C worst case most
(apart from obvious tropical species and succulents from Madagascar)
will hang on but may be marked. I keep very temperature sensitive plants
indoors for the winter since I cannot ensure reliable electricity in
winter storms. It is worth separating them and keeping the most touchy
ones at the blind end possibly inside a second skin well away from drafts.

It is amazing how well a bubble wrap curtain will help keep the warm end
a lot warmer than the end where the door is. My experience is actually
with a long thin greenhouse, but I think it will translate well to a
polytunnel.

Regards,
Martin Brown

"JennyC" wrote in message
...
I was wondering whether any URGlers have experience of keeping cacti
in a
polytunnel?

Any info regarding ventilation, heating in winter etc would be good.

Jenny,
Many cacti nurseries do just that. Just keep them dry and with as low
humidity as possible.

Many cacti in the wild survive naturally in those conditions - but not
all!
You will have to check on the natural environments of each species to
see which will cope and which will not. There will be some which will
require more TLC.

--
ned

http://www.bugsandweeds.co.uk
last update 09.07.2005

JennyC wrote:

I was wondering whether any URGlers have experience of keeping cacti in a
polytunnel?

Any info regarding ventilation, heating in winter etc would be good.


I generally keep my cactus as dry as poss in winter but 'frost free' in
our greenhouse.. Its bubble plastic lined & heated with a parrafin
heater.

I'd think condensation & humidity might be a problem in a polytunnel
tho?

Hardiness is relative but the most important thing seems to be keeping
them dry.

JimW
--
Plants etc on Ebay
Check it out
http://tinyurl.com/hi6g

"michael adams" wrote in message
...

"JennyC" wrote in message
...
I was wondering whether any URGlers have experience of keeping cacti in a
polytunnel?

Any info regarding ventilation, heating in winter etc would be good.
--
Jenny
(Rotterdam the Netherlands)
remove the squirrel to reply

If your question is - is it a good idea to devote years to
cultivating a wonderful and varied collection of choice cacti
which I will only be able to overwinter in a polytunnel, in a
region where the winter temperatures can fall below zero and where
it would be truly devastating for me to find large numbers of my
choicest 10 year old specimens turned to mush - simply as a result
of one really untypical cold snap, then the answer is probably no.

Well,,,,,,,,,,,, The loacation will be the Dordogne in France (if the house sale
goes through!)
It seems to be sligthly milder there than either the UK or Holland.

I have a glass GH at the moment, but was wondering whether a Polytunnel would
surfice until I can get myself organised properly (i'm not sure yet about
building restrictions as the house is in an area under monument rules)

possibility of moisture dripping onto the plants.

Right. hadn't thought of that.

Different authorities will give different answers as to the winter
hardiness of different species of cacti.

Photo's og my collection at: http://www.ljconline.nl/garden/Plantscacti.htm

Others such as Gordon Rowley have conducted their own
experiments overwintering various species of cacti and
succulents outdoors in the garden.
His findings which are more anecdotal than scientific tie in
with other work.

Are these on line ?
I'm a great fan of his :~))

Some species of opuntias for instance are surprisingly frost hardy -


Yes. Got one of those outside. It survives, but is not a thing of great beuaty.

.....- the only way to really find out might be the hard way.
michael adams

Ummmm. Perhaps not such a good idea after all :~(
Jenny

"JW" wrote in message
...
JennyC wrote:

I was wondering whether any URGlers have experience of keeping cacti in a
polytunnel?

Any info regarding ventilation, heating in winter etc would be good.


I generally keep my cactus as dry as poss in winter but 'frost free' in
our greenhouse.. Its bubble plastic lined & heated with a parrafin
heater.

Me too. I keep the GH at about 5 degrees C and the plants bone dry.
I bubble wrap the inside of the GH and have a small electric fan heater......
Jenny

In article , JennyC
writes


I have a glass GH at the moment, but was wondering whether a Polytunnel would
surfice until I can get myself organised properly (i'm not sure yet about
building restrictions as the house is in an area under monument rules)

I think your problem will be the damp not the cold. If you can keep them
bone dry in a dry atmosphere, they will tolerate cold better, if wetter,
then they won't be cold tolerant. So do whatever you need to avoid
condensation.

Trouble is that the damage isn't instantly visible. Plant seems to look
OK, it's only in the spring that the top falls in and you realise the
inside has rotted away long ago.

My greenhouse goes down to 40 deg F with occasional overnight drops to
34 deg. We always get a few losses, but only a few plants in a
collection of hundreds. We grow mammillarias, rebutias, astrophytums,
lobivias, gymnos, echinofossulocacti and a few other O&S


--
Kay
"Do not insult the crocodile until you have crossed the river"

"michael adams" wrote
,snip
There are tales of cacti in the old days being allowed to dry out
completely in the autumn, being removed from the pots, their roots
shaken out, then wrapped in newspaper, and stored in drawers in a frost
free atmosphere.
michael adams

So would a darkish shed be OK?
I thought they needed light, even un winter........
Jenny

"michael adams" wrote in message
...

"JennyC" wrote in message
...

"michael adams" wrote
,snip
There are tales of cacti in the old days being allowed to dry out
completely in the autumn, being removed from the pots, their roots
shaken out, then wrapped in newspaper, and stored in drawers in a frost
free atmosphere.
michael adams

So would a darkish shed be OK?
I thought they needed light, even un winter........
Jenny

There are most probably degrees of dormancy. Removing plants from
their pots - which presumably means fairly small specimans in any
case, and keeping them in the dark was presumably the lesser of two
evils as compared with any irreversable cold damage they might suffer.
Although presumably such plants might not perform as well as plants
which were overwintered in the light. It might also disturb the
flowering impetus etc and set that back a year or two. That might be
the main drawback. Or maybe precisely the opposite.

Any Southern hemisphere i.e South African succulents that haven't
been naturalised, and some cultivated epiphytes such as Christmas
Cactus would clearly be poor candidates for such treatments.

These "tales" never actually mentioned how many plants survived
such treatment. But providing the plants weren't attacked by pests
or diseases in the meantime, providing they had sufficient reserves
unless cacti can somehow "lose the will to live", I'd imagine
most would survive.

Or possibly trays of cacti could always be taken out of the shed
on any sunny days which could be guarenteed to stay dry.

Guaranteed maybe being the operative word.
michael adams

Thanks for all your excellent input Michael. I presume you have a collection
yourself?
Jenny