Clematis - pronounced "klem-a-tis" - from Klema, the Greek word for vine - are prestigious members of the Buttercup family. This family is botanically known as Rununculaceae. Don't try and say that with your mouth full! These exquisite climbers, which can be deciduous or evergreen, are so rewarding to grow and will delight with their beautiful buds, stunning blooms and fabulous fluffy seed heads. There are over 250 species in the Clematis family made up of scramblers, ramblers, climbers and perennials ensuring there is a Clematis to suit every garden temperament.
Situation - Clematis prefer their heads in the sun and their roots in the shade i.e. they need a cool root run with the ability to climb up towards the sun.
Soil - Plant deeply in soil that is humus rich and that does not completely dry out in summer. You may need to add a layer of mulch in summer to ensure the soil and root area stay cool.
Water - During the growing season and during summer water deeply (at least once a week) if there is no or little rainfall.
Feeding - Clematis will benefit from regular feeding with a balanced liquid fertilizer from early spring (just as the leaf buds are emerging) until flowering or if you prefer side dress with a balanced slow release fertilizer - you can use the same fertilizer you use on your roses. Clematis will also appreciate a little Lime being forked into the soil in late winter.
Cultivation - Though Clematis are very deep rooted plants take care when weeding close to the root area as the roots and also the plant stems are vulnerable to damage. The stems can be quite brittle and will split easily. Clematis are rapid tendril climbers and will need a support system in place prior to planting even if this is just a tree or rose for them to grow through, which will look fabulous BTW. Sometimes hybrid Clematis, especially the large flowered varieties can be susceptible to a fungal disease called "Clematis Wilt" AKA Phoma clematidina. The best prevention for this is growing your Clematis in the right conditions and avoiding root damage by planting deeply. A small amount of Trichopel incorporated at the time of planting can be a worthwhile preventative. If your Clematis does start to look a bit droopy and the leaves and stems have black discolouration cut back to a healthy part of the growing stem, making sure you destroy all the infected material. Clean up carefully around the base of the plant. A spray of sulphur may assist in killing the fungal spores and try not too worry this disease is not necessarily fatal.
Pruning - There are 3 main groups of Clematis and they are pruned according to the Group they belong to.
Group 1 - Prune lightly, if at all - Group 1 consists mainly of early flowering species and evergreen Clematis plus the Montana hybrids. These Clematis need little if any pruning other than the removal of dead flowers and a general tidy up if and when required.
Group 2 - Prune lightly - Group 2 consists of early flowering large flowered hybrids. Flat, single, semi-double or double flowers will appear on previous season's wood/stems and on new shoots from early to late summer. Generally the second flush of flowers is single even on semi-double or double varieties. Prune before new growth starts in early spring. Remove any damaged stems and cut back all other stems to where there are obvious new leaf buds. In general prune with a light hand and in fact this Group can be left un-pruned if preferred.
Group 3 - Prune Hard - Group 3 consists of late large flowered cultivars with outward facing, flat, single flowers that are borne on new shoots in summer or early autumn. Flowers can vary but are often star shaped. Prune in early spring before new growth starts removing all of the previous season's stems down to a pair of leaf buds approx 15-30cm above soil level.
Wairere Nursery 826 Gordonton Road, R D 1, Hamilton Ph: (07) 824 3430 Email: Open 7 days 8:30am-5pm