How to Propagate Hydrangeas from Cuttings? A Detailed Guide to the Latest Cutting Method
Hydrangea is a common potted ornamental flowering shrub. Its propagation methods include division, layering and cuttings, among other common methods. Among these, cuttings are what flower enthusiasts most want to use, as the operation is simple and the survival rate is relatively high. Below, the editor will introduce the cutting method for hydrangeas!
The Cutting Time for Hydrangeas
The most suitable time to take hydrangea cuttings is during the plum rain season.
The Cutting Method for Hydrangeas
1. Choosing the cutting medium: this refers to the nutrient soil, river sand, peat soil or other materials used for rooting cuttings. For home hydrangea cuttings, it is difficult to obtain an ideal cutting medium due to limited conditions. It is recommended to use a pre-mixed and sterilized cutting medium; medium-coarse river sand can also be used, but it should be rinsed several times with clean water before use. Do not use sea sand or river sand from saline-alkali areas, as they are not suitable for the growth of flowering plants.
2. Choosing the cutting stems: when taking softwood cuttings from hydrangeas, from late spring to early autumn when the plant is growing vigorously, select sturdy current-year branches as cuttings. After cutting the branches off, select the robust parts and cut them into sections 5-15 cm long, each section bearing more than 3 leaf nodes. When taking cuttings, note that the upper cut should be made flat about 1 cm above the topmost leaf node, and the lower cut should be made at an angle about 0.5 cm below the bottommost leaf node; both the upper and lower cuts should be smooth (the blade must be sharp). When taking hardwood cuttings, after temperatures rise in early spring, select healthy branches from the previous year as cuttings. Each cutting usually retains 3-4 nodes, and the cutting method is the same as for softwood cuttings.
Post-Cutting Care Methods for Hydrangeas
1. Temperature: the optimum temperature for rooting cuttings is 20°C-30°C. Below 20°C, cuttings root with difficulty and slowly; above 30°C, the upper and lower cuts of the cuttings are easily infected by pathogens and rot, and the higher the temperature, the greater the proportion of rot. When low temperatures occur after cutting, the main measure for keeping warm is to wrap the flower pot or container used for cuttings with plastic film. When the temperature is too high after cutting hydrangeas, the main cooling measure is to shade the cuttings, blocking out 50-80% of sunlight; at the same time, mist the cuttings 3-5 times a day. On sunny days with higher temperatures, mist more frequently; on cloudy and rainy days with lower temperatures and higher humidity, mist less frequently or not at all.
2. Humidity: after cutting hydrangeas, the relative humidity of the air must be maintained at 75-85%. The basic requirement for cuttings to root is that, before the cuttings root, they must be kept fresh and tender so they can carry out photosynthesis to produce rooting substances. However, cuttings that have not rooted cannot absorb enough water to maintain their internal water balance. Therefore, misting must be used to reduce water evaporation from the cuttings: under shaded conditions, mist the cuttings 3-5 times a day. On sunny days with higher temperatures, mist more frequently; on cloudy and rainy days with lower temperatures, mist less frequently or not at all. However, excessive misting makes cuttings susceptible to infection by pathogens and rot, because many kinds of pathogens exist in water.
3. Light: hydrangea cutting propagation cannot do without sunlight, because the cuttings still need to continue photosynthesis to produce nutrients and rooting substances to supply their rooting needs. However, the stronger the light, the higher the temperature inside the cuttings, the more vigorous the transpiration of the cuttings, and the more water they consume, which is not conducive to rooting. Therefore, after cutting hydrangeas, 50-80% of sunlight must be blocked. After the root system grows out, gradually remove the shade net: on sunny days, remove the shade net at 4:00 pm each day and put it back on before 9:00 am the next day.