Clematis varieties come in three flowering groups. The group one varieties flower in early- to mid-spring, earlier than the other groups. These clematis vines flower on year-old wood, so pruning must occur after the flowering period, or the flowering canes will accidentally be removed. Group one clematis mainly require pruning for aesthetic purposes, not for continued health. Clematis varieties in group one primarily grow in areas that experience little frost, since the 1-year vines can’t survive prolonged freezing.
Group one clematis do not require yearly pruning and only require pruning when the plants become overgrown, crowded or start flowering poorly.
Do not renovate the clematis more often than every three years. Overpruning weakens the plant and may result in vine death.