The main breeding method for peonies is division of rhizomes... This is a highly branching underground shoot, on which renewal buds or ocelli are laid. Shoots of the next year develop from them. The rhizome also has large adventitious roots, in which most of the nutrients accumulate. On the adventitious roots, small thin suction roots grow and die off annually, which take all the nutrients necessary for the plant from the soil.
Best dividing and transplanting times peonies - this is the period of growth of the suction roots. In our conditions, this happens twice - in the spring, in late April and early May, and at the very end of summer and early August. It is very good to divide and replant peonies at the end of summer when the air and soil temperatures drop. The last planting date is determined depending on the weather, the plants must take root reliably before the onset of cold weather and freezing of the soil. Later on September 15, it seems to me that this should no longer be done. Better to just dig in the delenki until next year. In our conditions, spring division is also undesirable, since in this case the division, not having enough time to take root, goes into the phase of active growth of shoots. As a result, the plant, at least in the first year, does not develop well and may die.
The growth of the underground part in peonies is slow. For division, specimens at least 3-4 years old are suitable. These plants are easy to dig up and divide. Older peonies, which have not been divided for many years, are difficult to dig up, pieces of roots remain in the ground, which can later give rise to a new plant. The site becomes clogged when it is difficult to determine which variety it is and where it came from.
By the way, you never need to transplant an entire adult plant. It is obligatory to share it. By dividing, we rejuvenate the peony. In addition, a transplanted peony with a large rhizome and a large number of eyes takes root much worse and can also die. The best standard cut should have approximately three well-developed buds and at least two adventitious roots from 5 cm long and one centimeter thicker. Such a division provides the supply of nutrients necessary for rooting.
Cut off the stems of the peony intended for digging, remove the earth around the bush and remove the rhizome, trying to damage the fragile adventitious roots as little as possible. It is better to cut them, leaving no more than 10-12 cm in length. The soil particles are gently washed off. The rhizome is placed for 1-2 days in a dark, dry place for drying. During this time, the rhizome loses its fragility, and the remaining earth crumbles.
Sometimes the rhizome disintegrates itself into its constituent parts, but mainly requires division. Cut the rhizome with a sharp knife. If the peony is very old, then a chisel and a hammer may be needed. When dividing, care must be taken to maintain a balance between the number of buds and the volume of roots (more buds - more roots), and the cut area is minimal. Rotten places are cleaned to healthy tissue, the cuts are sprinkled with crushed coal.
The finished cut is kept for 2-3 days in a cool shaded place in the air, so that the wound surface dries up sooner. If it is required to keep it longer without planting, then it can even endure long-term transportation in sand or moss.
Peonies are exceptional long-livers among ornamental herbaceous plants. Many varieties of peony lactobacillus can bloom beautifully without transplanting for 25-50 years. In hybrids of medicinal peony, the period of active growth is much shorter - 7-15 years.
To pion for many years it has grown successfully and bloomed well, enough fertile soil is needed. It is good to use rotted manure.Since the peony prefers neutral soils, it is necessary to add ash of at least a glass (I usually put ash about a liter can), about 1-2 glasses of phosphorus fertilizers. The pit is at least 60 cm deep, but the roots of an adult plant should not reach the groundwater level. All fertilizer is poured into the lower part of the pit, and the cut is placed in the upper layer without fertilization. The planting depth should be such that the renewal buds are buried no more than 3-5 cm from the soil level. Otherwise, the peony will not bloom for many years.
Another way of breeding peonies is root cuttings... In the spring, a peony bush is dug out on one side and the adventitious roots are at least 1 cm thick. They are cut into pieces 5 cm long and planted to a depth of 3-6 cm in loose nutrient soil without fertilizers. Water well all summer. Renewal buds are laid and germinated in 2-4 years. However, not all peonies are capable of forming renewal buds on adventitious roots. In this way, some interspecific hybrids (Carol, Helen Cowley, Karina) and varieties of medicinal peony can be propagated. I remember once sharing a peony "Baroness Schroeder". There are many adventitious roots left. One friend of mine was very sorry that she could not get this peony. I suggested that she take the leftovers, not hoping, however, for a result. Imagine my surprise when, 5 years later, she told me that her peony did not just grow, but blooms perfectly.
Can also be used for breeding pruning method... This method can be used for peonies over 5 years old with a lot of shoots. In the usual terms of division, the plant is dug up to such a depth as to expose the rhizome to a height of 5-7 cm. The entire top is cut horizontally with a sharply sharpened shovel. The resulting small cuttings are grown on the garden bed, and then transplanted to a permanent place. The cut of the remaining plant is treated with wood ash and covered to the previous level with fresh soil without fertilizers. After two years, the peony is fully restored.
There is also such a fairly simple, but I would say, not quite a cultural way of breeding - cutting off part of a bush... True, it was with this division that I got the magnificent peony Sarah Bernhardt, which has been blooming for more than 10 years, and I myself also had to resort to this method once. And yet I don't really like him. So, about the method. At normal times, the surface of the rhizome is exposed. A part of the plant is separated with a sharp shovel vertically, the rest is sprinkled with earth, having previously processed the cut with coal. This method is considered not very effective, since little planting material is obtained, and the remaining bush can hurt. True, I did not notice this in my peony, but nevertheless it is a big trauma for the plant.
Thus, there are many ways of vegetative propagation of peonies. Their choice depends on the goal. It's one thing when you need to get a lot of deals for implementation, and it's another thing to give someone a very favorite peony variety. It seems to me that the usual way of dividing pions is the most physiological and simple and gives a good effect when used correctly.