Clematis in April: monthly care

Clematis 'Jackmanii' thrives in full sun or partial shade, ideally with its roots in cool shade and its head in the sun. Choose a position against a wall, fence, trellis, or pergola where the plant can climb freely. This cultivar tolerates both loam and chalky soils, but the ground must be well-drained yet moisture-retentive. Before planting, dig a hole roughly 45 cm wide and deep, and work in plenty of organic matter such as well-rotted compost or manure to improve soil structure and fertility. Plant between March and May or in September and October. Set the rootball about 8–10 cm deeper than it sat in its pot; this encourages new shoots to develop from below ground and helps the plant recover if clematis wilt strikes. Space plants 200 cm apart if you're planting more than one. Spread the roots gently in the planting hole, backfill with improved soil, and firm in carefully. Water thoroughly immediately after planting to settle the soil around the roots. Apply a 5–8 cm layer of mulch such as compost, bark chips, or gravel around the base, keeping it a few centimetres clear of the stems to prevent rot. This mulch keeps the roots cool and conserves moisture. Install support at planting time—clematis 'Jackmanii' climbs by twining leaf stalks, so provide canes, wires, or trellis with gaps of 10–15 cm. Tie in the main stems loosely with soft twine to guide initial growth, and water regularly during the first growing season until the plant is established.

Water clematis 'Jackmanii' regularly during the growing season, especially in dry spells. The roots need consistent moisture but must never sit in waterlogged soil. In spring and summer, water deeply once or twice a week if rainfall is scarce; in autumn and winter, natural rainfall is usually sufficient. Mulch helps retain moisture and keeps roots cool, so top up the layer each spring if it has thinned. Feed in March or early April with a general-purpose balanced fertiliser such as blood, fish, and bone or a slow-release granular feed, scattering it around the base and watering in well. Apply a second feed in June, ideally using a potassium-rich fertiliser such as tomato feed to encourage flowering. Avoid high-nitrogen feeds after spring, as these promote leafy growth at the expense of blooms. Clematis 'Jackmanii' is fully hardy in zones 4a–9b and needs no special winter protection in temperate Europe. The hard pruning in late winter naturally removes any frost-damaged growth. However, young plants benefit from a thicker mulch layer in their first winter. Watch for clematis wilt, a fungal disease that causes shoots to collapse suddenly, usually in late spring or early summer. If it strikes, cut affected stems back to healthy tissue below ground level; new shoots often emerge from the base thanks to the deep planting. Aphids, earwigs, and slugs can damage young growth—check regularly in spring and remove pests by hand or treat with an appropriate organic control. Powdery mildew may appear on leaves in dry summers; improve air circulation and water the roots, not the foliage.