If you grow fall-flowering clematis vine, you should learn to recognize the early signs of pest infestation. With the proper care, your clematis will be healthy enough to survive most invasions.
One pest that loves fall-flowering clematis is the aphid. Other potentially serious pests include clematis borers, which cause stems to die, earwigs and root knot nematodes. Since ladybugs will likely eat the aphids, the other pests are a bigger cause for concern.
If the autumn is particularly moist, your clematis may suffer from stem rot or wilt, caused by the Ascochyta clematidina fungus or powdery mildew. While you can treat mildew, which looks like a white powder, stem rot is most often fatal.
To prevent aphids and other insects, use an insecticidal soap on your clematis. Planting in well ventilated places in the garden should reduce the risk of fungal infection.