|Early this spring I bought a specimen of Clematis x cartmanii 'Blaaval'. Up until recently it appeared to be flourishing. Now it appears to be infected with Clematis wilt. It has all the classic symptoms. I have cut back all the wilted shoots meant basically cutting away the entire plant. At this time of year I am not too optimistic about it coming back. Since I love the display at the entrance to my garden I would like to try again with a new specimen.
1. Would you suggest the same cultivar? I do like the 'avalanche' display. Is there another Monrovia cultivar that will give me a similar display but be more resistant to Phoma clematidina?
2. What steps should I take before planting a new specimen?
3. How long should I give the existing Clematis before I decide to invest in a new plant and what signs should I look for to indicate it may survive?
|The cause of clematis wilt is really unknown but the most common theory is that it is caused by a fungus. Presumably this is a very selective fungus that can attack shoots, leaving the root system healthy.
Another theory is that snails or slugs attack the stem of the plant causing a portion of the plant to be cut off from its water. Other possible causes are genetic weakness due to hybridization or damage caused burrowing animals such as moles, chipmunks, or voles(mice) that disturb or feed on the root system causing the plant to prune itself accordingly.
Others have observed that clematis, even large flowered hybrids, that are planted in a spot where there is a subsoil water source such a spring, a stream or at a river bank, wilt is almost non-existent. The wilt is truly a mystery. University studies, supported by the British Clematis Society and others, into the exact cause(s) of clematis wilt are presently under way in England.
The good news is that wilt is rarely fatal to the plant. It might take up to a year, but the plant will usually sprout a vigorous shoot from under the ground to live another day. If you've cut away all the above-ground growht, make sure that the plant is well marked so you know that the new shoot that emerges next spring is not a weed. I think it will recover. Best wishes with your clematis!