Plant Diamantina Clematis in well-drained soil with full sun to partial shade. Ensure the soil is rich in organic matter. Water regularly, keeping the soil consistently moist but not waterlogged. Provide a trellis or support for climbing. Prune in late winter or early spring, cutting back to strong buds. Fertilize in spring with a balanced fertilizer. Protect from strong winds and ensure good air circulation to prevent disease.