On 22/07/2013 09:17, Charlie Pridham wrote:

"Jeff Layman" wrote in message
...
Just had a "Vyvyan Pennell" curl up as it was about to flower. :-(

A couple of weeks ago a small x triternata rubra went down. Not sure if
that was wilt or not, but the hot weather won't help matters with
early-morning high humidity.

Anyone else had their clematis suffering from wilt?

(A question for Charlie. Is there anything the professionals can use to
prevent or treat it? Or is there nothing available even to commercial
growers?)

--

Jeff

Hi Jeff,

Wilt as a disease has no known chemical cure however is a relatively rare
disease that only affects those clematis with far eastern blood (typically
those with large flowers) most clematis that wilt have suffered some other
event not to their liking. Nurseries don't need a prevention treatment as I
have never known a plant suffer from it, probably because we water every day
and keep the wind and rain off the plants!

Wilt the fungal disease is an air borne fungus that cause minor leaf
spotting on European clematis like viticella, it does not survive in soil
(hence the plant deep advice) so its OK to replant but I have to say it
rarely if ever actually kills plants. However the far eastern clematis have
no natural immunity to it and it travels from the leaves to infect the stems
blocking the sap flow causing the wilting we see.

Your Vyvyan Pennell probably did have wilt as it is the number 1 wilter and
very prone
Triternata Rubro Marginata is just an annoying plant that is difficult to
find the right spot for but once found grows like a weed, here the problem
seems to be that it gives up very quickly if attacked by snails/slugs.

Nick, sadly Florida is only really going to do well under glass it just
doesn't like weather and needs very sharp drainage round the crown of the
plant

Things that help

If you suffer a lot stop buying group 2 clematis and switch to group 3!
If you already have plants, heavy watering in May helps, as does very strict
slug/snail control from January on and making sure that the plant is
properly tied in and cant move in the wind.

Growing large flowered clematis in pots for a couple of seasons to get a big
well established root system can work well.

Plants often grow out of it and this is more likely due to their increased
root systems coping with water stress better rather than becoming resistant
to the fungus

Hope all that helps


Thanks, Charlie. Useful info.

We inherited the Vyvyan Pennell when we moved here; I would guess it is
at least 5 years old, probably more. The previous owner said it had
never done well. It's at the base of a north-facing wall (about 18
inches high). Gets full sun most of the day, and was soaked throughout
May with all that rain. It's well supported with a frame. Out of
interest I'll dig it up when it's dormant next winter, wash the soil
off, and move it somewhere else.

The X triternata rubromarginata was in a largish pot in full sun, but
very exposed to the wind. We had it in the ground in a sheltered
south-facing position in a previous garden, where it climbed through a
Chamaecyparis pisifera, easily attaining 10 ft each year. Never saw
slug/snail damage even though they ate everything else in the garden!

We'll take your advice to stay away from the group 2 clematis from now on.

--

Jeff