A brief discussion on the principles of root germination
Today's sharing of small experiences: content about common sense of flower cultivation, a brief discussion on the principles of root germination. Next, the editor of this site will introduce to everyone.
There are several basic principles of plant root growth, here are some simple discussions:
1. Suitable air humidity, air humidity does not refer to soil moisture. When humidity is relatively high, such as reaching 99% saturated air humidity, plants can even germinate roots in the air without needing to contact soil media. Many people fail in humidity because it is not due to insufficient air humidity (generally, the humidity of a balcony environment can reach 80% during the plum rain season, usually around 55%, and it may be drier in the north), so closed greenhouse plants are easy to propagate by cutting. Many people fall into another misunderstanding, which is high soil moisture. Soil moisture does not need to be very high because the roots do not absorb water at that time or even do not have roots. The soil maintains a certain period because it provides high humidity for the attached air of the plant.
2. Suitable hormone levels, we often properly dry the plants in the early stage to heal wounds and let the plants shrink appropriately. When plants shrink, they lose water, but the concentration of hormones in their bodies increases. Root germination requires hormone levels. Some plants have low hormone levels and need to be supplemented with naphthylactic acid root powder, such as Echeveria cuttings, which can improve the effect when coated with root powder. On the other hand, some plants have very high hormone levels and can easily germinate roots, such as Sanjigon. Even if you apply root powder, it does not germinate because excessive naphthylactic acid can inhibit root growth.
3. Appropriate lighting, we all know that light promotes the flow of plant sap and transpiration. However, as mentioned earlier, hormone levels can cause plant hormones to flow to the top of the plant rather than the base needed for root growth when light intensity is high. This can cause some plants to germinate easily, such as Sempervivum and cacti, while Agave species may germinate better with some light intensity, so it depends on the specific variety. Light intensity also causes plant transpiration, which means the plant gets dried out. Therefore, for plants that have shrunk to a certain extent, such as Benikusa (also known as Shokijusa, the Chinese common names are usually very informal), the hormone levels are sufficient, but without roots to supplement water, the sap almost solidifies, and the high hormone levels are ineffective.
4. Suitable tissue, everyone knows that taking a petal to cuttings will not root, but we often think that many positions that can be cut are difficult to cut, such as old lignified stems. I once had over 40 selected Dongxing plants rot last year because I used old lignified large plants to cut. After a few months, the base still did not germinate roots. The plant tissue there was too old and it was difficult to germinate new root buds. In that post, I also saw a pretty big head, and actually these big heads without a bit of base are not easy to germinate roots. In greenhouse propagation, this is very clear. For example, with the leaf cuttings of Akebi, roots usually germinate after 2 weeks, but when making the head, it looks like there are more leaves in better condition, and it takes a month to start rooting. Conversely, overly small tender tissue is also not easy to survive, although these tissues are稚嫩 and active, but when they are too small, they do not have enough stored nutrients and may die before the roots germinate. Therefore, it is important to choose suitable tissue. Now, it is often seen online that small Sempervivum buds below 1 centimeter or Agave seedlings with 2-3 leaves are difficult to keep alive. Even if they survive, the recovery period is very long. For example, with a 10-centimeter-long Jixie bud, you can make it grow very vigorous within a year, but with less than 5 centimeters and 2-3 leaves, you may only see it grow 1-2 leaves in a year, still as a bud. It is already difficult to keep such a small seedling alive, and it takes at least 2-3 years more than a 10-centimeter seedling to grow into a standard plant.
5. Good healing, after the wound is cut, various bacteria may infect the wound. When they infect severely, the tissue becomes necrotic. Although you may only see a little infection on the surface, there may be many internal菌丝. The toxins produced by these bacteria affect healing and germination, so good wound treatment is crucial. Infection sometimes has a significant impact on germination. Sometimes cuttings do not grow roots for a long time and even rot suddenly due to infection. The reason is infection, so post-cut treatment is very important. Tissue with roots, when the roots shrink, heal, or fall off, the remaining wound is smaller and easier to heal, while the reason leaf cuttings are difficult to survive is that leaf wounds are easily infected. Cut tissue must be dried, which is different from cuttings. At this time, dry air is beneficial for tissue healing. For plants with a lot of sap, you need to dry the wound with paper towels in time to avoid unhealed sap flow that causes bacteria and mold to thrive and affects the wound. Properly drying the plant, even to a certain degree of shrinkage, before cutting is good for both Sempervivum and cacti.
Finally, here is a safer solution for a balcony: first, let the plant tissue dry to an appropriate degree of shrinkage, then use a flower pot, and place some medium-sized vermiculite on the surface of the soil that contacts the tissue because vermiculite has few bacteria and less decomposable organic matter. (I do not recommend disinfecting cutting soil because although the soil is clean at first, mold may爆发 later because there are no other microorganisms to inhibit mold. The dominant mold is the first to arrive. If conditions allow, planting EM bacteria in the soil is recommended.) Then, water thoroughly, cover the pot with a plastic bag, and remember to puff up the plastic bag with your mouth. This breath is important because high concentrations of carbon dioxide are food for plants, as everyone knows who grows hydroponic plants. Place it in a semi-shaded area and wait. This cutting method has a high success rate, creating a local high carbon dioxide, high air humidity, and relatively safe medium environment.个别 unsuccessful cases can only be blamed on personal luck, and this failure probability cannot be avoided by anyone, including the most professional nurseries.
The full content of the discussion on the principles of root germination is provided above, hoping it is helpful to green plant enthusiasts!