Clematis is suitable for greening walls, arbors and trellises. Planting time for this popular climbing plant is August. With this planting guide clematis will grow safely.
There are several groups of clematis with different growth vigor and flowering time. The spring bloomers grow particularly vigorously, for example the alpine clematis (Clematis alpina) and the anemone clematis (Clematis montana). Clematis hybrids, on the other hand, bear the largest flowers. Some varieties even bloom twice a year, like modern roses. Clematis hybrids grow the weakest and rarely reach more than 3 meters / 10 ft in height. They are also somewhat more sensitive than the other groups.
The varieties of the Italian leather flower or purple clematis (Clematis viticella) are considered particularly robust. Like all wild species, they are largely resistant to root fungi that cause the dreaded clematis wilt. Purple clematis bloom exclusively on new shoots and therefore usually do not show their first flowers until the end of June.
How to plant clematis
When to plant clematis?
Clematis are offered as container plants and can basically be planted all year round. However, the best time for planting is late summer from August to October, because then the soil temperature between 14 and 22 ° C / 57 and 72° F is optimal and ensures good root growth. Thus, the plants can easily get through the winter. Planting in late summer also has the advantage that the already rooted climbing plants start the next year without delay in the new season and already bloom profusely in the first year.
The ideal location for clematis
Wild clematis grow in deciduous forests and climb through the treetops towards the light. Therefore, even in the garden, they like to have their heads in the sun and their feet in the shade. Therefore, choose a sunny but not too hot location for your clematis. West-facing house walls or climbing beds under taller trees with a light crown are ideal.
The lower 30 to 50 cm (12 to 20 in) of the plant should be shaded in any case. Dense, but not too spreading perennials such as alumroot, bluebells or funcias work well for this. If very dominant perennials such as lady’s mantle or rock crane’s-bill grow in the neighborhood, the root area of the clematis should be shielded with a root barrier, such as pond liner or concrete lawn borders.
What soil do clematis need?
Like all woodland plants, clematis prefer a humus-rich, evenly moist soil with good water drainage. On heavy soils, dig a hole large enough and deep enough, and fill the bottom 10 cm (4 in) with sand or grit to prevent water from accumulating. If waterlogging occurs, the roots will begin to rot and the plants will become very susceptible to clematis wilt. The excavated soil is best mixed with plenty of sand and compost, half-decomposed leaves or normal potting soil.
Planting clematis correctly
Submerge root ball
Carefully pot out the clematis. For heavily rooted plants, cut open the pot or foil bag so you don’t tear off the delicate shoots. Place dried out pot balls in a bucket of water for a couple of hours to allow the soil to soak up properly. Place the pot in it until no more air bubbles rise.
The planting hole should be deep enough for clematis so that the surface of the bale is later below ground level and the first shoots are thus well protected. Add a drainage layer of crushed stone to the planting hole. If necessary, mix the excavated soil in a bucket with sand and compost or potting soil.
Then fill in the excavated soil again and press it lightly with your hands. The ideal location is a deep, loose humus soil in a semi-shady place.
Apply a layer of mulch
Water the plant thoroughly and finally apply a layer of bark mulch, pebbles or pine bark about ten centimeters thick to protect the root zone from drying out and severe temperature fluctuations.
For a clematis growing under a tree, regular watering remains important in the future. So that the shoots quickly find their way to the light, they are guided into the crown on wooden sticks. When planting in late summer, you should refrain from fertilizing, it is postponed until the next spring.
The right climbing aid for clematis
All clematis hold on to their climbing aid with the help of elongated leaf stalks, so-called leaf tendrils. Wooden trellises made of horizontal and vertical strips with an edge length of about 2 to 2.5 centimeters (0.8 to 1 in) are optimal. Steel, for example galvanized structural steel mats, are often recommended as climbing aids, but are not the first choice. The reason for this is, that metal is subject to strong temperature fluctuations depending on the weather and can therefore cause frostbite on the shoots.
How to mount the climbing aid
The trellis should be mounted at a distance of about 8 to 10 cm (3 to 4 in) from the house wall, so that the back side is also well ventilated. The size depends on the particular clematis: for the weak-growing hybrids, a two-meter (80 in) wide and three-meter (120 in) high trellis is quite sufficient. Strong-growing species such as the anemone clematis, on the other hand, can simply be left to grow up a pergola. After planting, all you have to do is secure the shoots to the pole with a few loose binding wires. Once the plant reaches the pergola’s crossbar, it will do without any further support measures.
It’s important to install the climbing trellis right at planting, after just one year, it will be difficult to untangle the unguided shoots without pruning. After planting, remove the support rod and direct the main shoots through the trellis in a fan shape.