How does the grafting of plants work?
Most gardeners have certainly heard the term "grafting". But what is actually meant by grafting plants? Grafting means that a new plant is created from two plants. Trees and shrubs are propagated in this way. Roughly speaking, the gardener takes a branch with buds from one plant and attaches it to the trunk of another plant to create a new plant. This is known colloquially as grafting - although it is only one of many grafting methods.
Why are plants grafted?
Now the question arises as to why gardeners should graft their plants at all? After all, plants can reproduce independently using seeds. This is true, but some ornamental plants, fruit trees and shrubs are not able to grow strong young plants from their seeds. On the contrary - natural propagation often results in the plants becoming weaker and weaker, so that they are ultimately unable to survive. When grafting, the gardener ensures that the good characteristics of the respective plant are passed on in their purest form. If noble plants are to be preserved over several generations, there is no way around grafting. Or if a noble but susceptible plant needs a robust root system, the gardener will graft the plant with a frost-proof base, for example, so that the plant as a whole is more stable and healthier. Advanced gardeners can also create completely new varieties with grafting.
But first things first. Let's first take a look at which plants are suitable for grafting. Fruit trees, vines and roses are plants that are suitable for grafting. But also vegetable plants such as tomatoes or cucumbers. Typically, only plants of the same genus are grafted together. So pear with pear and apple with apple. However, crosses are also possible - here it is important that the genetic material is as identical as possible. Quince and pear, for example, harmonise quite well with each other.
Scion and rootstock
Gardeners need two plant parts for grafting: The rootstock and the scion, which is a one-year-old, unbranched shoot about 30 centimetres long and as thick as a pencil. The new plant grows from the scion. Gardeners can obtain this shoot from tree nurseries or fruit and horticultural organisations. There is also nothing to stop you from harvesting scions from your own apple tree - preferably with sharp pruning shears or pruning shears. This is done during dormancy, i.e. from December to February, if grafting is planned between late winter and spring. It is important to store the scions in a cool and moist place after harvesting. A cool box is recommended even for short journeys. At home, the scion can be wrapped in foil and stored in the fridge.
The rootstock, also known as a wildling, helps the plant to develop vigorously and healthily. Gardeners often choose rootstocks that are frost-resistant, attract few pests and form a strong root ball - characteristics that are transferred to the entire plant when it is grafted.
Grafting, copulating, oculating - methods of plant grafting
There are three basic methods for grafting plants: copulation, oculation and grafting. Grafting is a simple and widely used method that quickly leads to success, even for amateur gardeners.
Grafting
In short, grafting involves grafting a scion during dormancy (can be artificially extended in the refrigerator) onto a sap-laden rootstock. The best time for this is from April to May. First, the rootstock is cut off close to the ground and as straight as possible, then the bark is opened up at one point with a cut using a grafting knife - this is relatively easy because the rootstock is already in sap. The scion is then inserted into this opening at an angle and then fixed and sealed with grafting wax - as is the tip of the scion. The grower wraps the rootstock with raffia or adhesive tape.
- Time: April to May
- The rootstock is in sap and is significantly thicker than the scion
- Suitable for propagating noble varieties
Copulation
The second grafting method, copulation, helps to graft young fruit trees. The most important prerequisite is that the rootstock and scion have the same diameter. This grafting method usually takes place from February to April. The scion should be dormant, the rootstock can already be in sap, but does not have to be. The scion and rootstock are now each cut at an angle using a copulating knife or a pruning knife. The two parts of the plant must then be joined together as well as possible. A raffia string or adhesive tape is again very helpful here. Finally, the tip of the scion is sealed with wax.
- Time: February to April
- The rootstock and scion are the same thickness
- Scion is dormant, rootstock can already be in sap, but does not have to be
Occulation
The third and most complicated grafting method is occulation. It is used in tree nurseries and garden centres to obtain a large quantity of young plants - mainly fruit trees. In contrast to the other two methods, this takes place in summer. In addition, oculation does not require the entire scion, but only the buds (eye). The scion eye is carefully removed from the rice using a oculation knife. Cut it flat and add a small shield of bark and wood at the top and bottom. Then cut a T-shape into the bark of the base so that the eye can be attached to it. Fasten the two together again (raffia or adhesive tape) and seal the top of the base with wax.
- Time: July - August
- Scion and rootstock are in sap
- Suitable for producing large quantities of fruit trees
There are many specialised books on grafting plants, the optimum pruning and pruning fruit trees - gardeners can read up on the subject in detail here.
As so often, the same applies here: Just try it out!
