HOW TO PROPAGATE CLEMATIS

Clematis are propagated nowadays mostly by cuttings, but not with a heel or a joint at the bottom of the cutting, which is just as well as clematis have such a long stem in between each node that cuttings with a node at each end would be far too long. Clematis root fortunately very easily on the stem, so all that is needed is a short length of stem below the node. So, as one cuts the stem in between the nodes they are known as internodal cuttings. Large-flowering hybrids are very difficult to root if taken from an established plant in the garden. The ideal wood is thin young wood from a one-year-old plant that has been forced on in a greenhouse and this is the way in which modern Nurseries produce their plants these days. May or June is the usual time of the year when cuttings are taken. Pots or seed trays are filled with sharp sand and peat in equal proportions. The cuttings are inserted not too thickly into the pots, ten of twelve to a 5-inch pot. They are then watered in well and put into frames in the greenhouse with some form of bottom heat. Keep them close and moist, checking every few days to see that no leaves have rotted off, in which case they must be removed. Shade them when the sun is out and in a few weeks time they will have rooted. They should gradually be hardened off and can then be potted up into individual pots.

The soil in this case should be a light sandy soil, John Innes No. 1 or Levington Potting Compost. They can be left in these pots for the rest of the year standing in the greenhouse or a frame, and during the winter potted on into larger pots and kept either in the greenhouse, or plunged outside in peat or ashes.

They are perfectly hardy and will stand this treatment even in a hard winter. During the following summer they will make nice plants of up to 3 or 4 feet high and can be planted out into their permanent place in the garden in the autumn.

Seed is another way of propagating clematis but as only a few of the species will come true from seed this is a very chancy business. Hybrids will not come true from seed at all and one gets all sorts of peculiar and uninteresting varieties by this method, but it is by this method that new varieties occur. One of the snags of seed sowing is that seed takes anything up to three years to germinate, except for some of the species which will come up the same season.

C. tangutica and C. davidiana, for instance, come up very quickly. Seed should be gathered in the autumn on a dry day as soon as it is ripe and kept in a cool dry place. In the spring they can be sown in a seed-sowing compost in seed pans or pots. Larger seeds can be sown fairly deeply, but small varieties such as tangutica or davidiana need only just covering. Most clematis have long tails on them which make up the attractive seedheads. The seeds are joined together on a tight ball with all the feathery tails sticking outwards. This ball of seed, when dry, can be easily broken up for sowing in the early spring. Seed with only small tails can be sown fairly easily but some of the hybrids are more difficult to cover and it is perhaps a good idea to dibble them in with their tails sticking up out of the ground. At least one would not sow too thickly by this method. Once the seed has germinated and the first pair of leaves appear, lift them carefully out of their pan and pot each individual seedling into a John Innes No.

or Levington Potting Compost. If nothing has appeared by the early summer stand the pans outside in a cold frame or on the north side of a building so that the sun does not bake them bone dry, and leave them there until the following spring, letting them weather with frosts and snow during the winter. This will sometimes encourage them to germinate quickly if brought into the warm greenhouse in the following spring.

Grafting is a commercial method now used less and less by Nurserymen. Before the Second World War most Nurseries employed the grafting method to propagate, but since it has been discovered that clematis will grow equally well from cuttings, grafting has fallen out of favour and most Nurseries rely on internodal cuttings to produce their plants. The one advantage of grafting is that a plant grafted in March will be a saleable plant in July and will flower well the first year. We always graft a certain number of plants mainly to get a good show of flower from July to September when many visitors are about in the coastal area of Suffolk, and call to look round the Nursery. The opponents of grafting have always suggested that this method encourages clematis wilt, but this is nonsense. They say that the grafted plant is not on its own roots to the great detriment of the clematis, but again this is not true because a clematis is not grafted permanently on to its stock. The stock is simply used as a nurse stock to get the scion over its first six months, after which it will develop its own roots, and by the time the clematis is planted in the autumn the scion will have taken over and produced its own root system, the root stock will be discarded and will die away during the winter. Provided of course that when potting on the young grafted plants from small pots into large ones, the union is potted well below the level of the soil in the pot.

Clematis are grafted on to native English clematis, Travellers Joy, or to give it its correct name

C. vitalba. Seed of this is sown outside in drills in the spring and the seedlings are fit for grafting in their second year, which means that the scion has a two-year-old root to supply it with all its needs for those important six months. These wild clematis are lifted in the winter and brought into a frame or cold greenhouse with the roots covered with peat or soil to encourage them into gentle growth. At the same time stock plants are brought into a warm greenhouse to encourage them to produce 3 or 4 feet of strong young growth. When this has happened, usually in March, they are ready for grafting and a handful of stocks are brought in ready for the operation. The young growth of the named variety is cut and prepared by cutting it into sections, one pair of leaves to each section, which will provide two scions each. The top growth of the stock is removed and a suitable straight part of the root is selected for grafting. A clean straight cut is made along the top part of this root about an inch long, just paring off the bark. The section of the hybrid is then prepared by cutting straight down between the pair of buds leaving the leaf on, thus giving you two scions. The cut is then tapered off to fit the cut on to the stock, a simple way of grafting known as whip grafting. Before this some thin pieces of raffia are prepared and soaked in water to make them soft and pliable. Then carefully fit the scion to the stock making sure that the bark fits on both sides, for it is here that the union takes place. Hold the stock and scion together and bind them firmly but gently with the raffia, taking a turn or two above the bud and then tying round and round until one reaches the base of the cut when one finishes off with a half hitch. Trim off any part of the stem and scion sticking up above the binding and your graft is complete and ready for potting into a 2^-inch pot into a John Innes Compost No. 2. Place the pots into a shaded propagating frame with bottom heat and keep them close for three or four weeks in a temperature of about 69°F, looking at them occasionally to see if they need watering or to see that the leaf is not damping off. Spraying with Benlate will prevent this. After three weeks look at the bud at the bottom of the leafstalk, which should by now be swelling. When it is V6 inch high it

is time to take them out of their close quarters on to a more airy bench in the greenhouse. Keep them shaded when the sun is shining as in March and April it can get very strong through glass and soon shrivel up the tender little shoot. When they are 3 or 4 inches high they should be given little sticks to support them and be stopped by pinching out the growing tip, to encourage them to break into two shoots. Clematis are very hardy plants and do not like too much heat, so as soon as possible put them into a cooler house and ventilate well on hot days. They are now ready for their final potting into 5-inch pots, which are known in the trade as ‘long toms’. Use a Levington

Compost or a John Innes No. 3, making sure when potting to see that the union is below the level of the soil in the pot. There is little else to do, except to stake the plant with a bamboo cane, see that it is kept well watered and fed at the proper time, and tie the plant to its stake as it grows. By July it will be at the top of the cane and in bud, you can either keep them in the greenhouse, or plant them outside in their permanent spots, and if you are not ready for this yet, they can be plunged outside in the ground in their pots, covering the pot completely, which will keep them moist for the summer, planting them out in the autumn.

The best and easiest method of all to increase clematis is by layering. There is no need for greenhouses, bottom heat, stocks or special soil. All one needs is a well-developed plant with several stems that can be lowered down to the ground and layered at the point of impact with the soil. This can either be done by layering them directly into the soil, adding a little sharp sand to encourage rooting, or to sink pots into the ground containing some John Innes No. 3 and layer directly into the pot so that when lifting them in a year or eighteen months time the roots are not disturbed. August is the best month for layering as the wood has ripened by then, and taking the method of sinking pots we will proceed. Sink as many pots filled with good soil as there are vines to layer, and at the point of impact bend the vine down to the soil, making sure that when bending too much strain is not put on to the vine which may snap. At the point in the stem where it touches the soil in the pot make a lengthwise cut along the bark and dust this with a hormone powder to encourage rooting. A twist can be made instead of a cut, making sure you break the bark and not the vine. Prepare some pieces of stout wire bent double to form a hairpin and peg down your vine in the pot. When this is done, cover with soil and place a stone on top to keep the layer from springing up. Then go away and leave the plant alone for a year or eighteen months! What could be simpler? Except for the fact that the plant must be kept well watered and fed every week and making sure that the pots of soil do not dry out either. At the end of this long period of time, which usually pass in a flash, try tugging the end of the vine which we have left sticking up out of the soil, if it stays firm then the layer is successful, and one can sever the vine on the plant side of the pot, lift the pot from the soil and lo and behold! we have a well-rooted plant to put in another spot in the garden or to give to a friend, doing the poor Nurseryman out of business! Actually, however, encouraging the recipient to get another different-coloured clematis, then to find out there are many more varieties, to get the clematis fever and buy more and more, and so the Nurseryman is able to survive after all in spite of our efforts to make him bankrupt!

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