Propagation Method and Technique for Softwood Cuttings of Golden Privet

Softwood cuttings of golden privet

Golden privet (Ligustrum × vicaryi) is a small shrub of the genus Ligustrum in the family Oleaceae. Its young leaves are golden yellow, while the older leaves are green and glossy. It is highly adaptable and requires only extensive management, making it a commonly used tree species in landscaping today. A brief introduction to the softwood cutting propagation technique for golden privet is given below.

1. Site selection and land preparation: Choose a loose, fertile, flat plot with good drainage. Apply 125 kg of superphosphate per mu, deep plow 15 cm, then break up the soil and rake it level. Make raised beds 1.2 m wide with furrows 20 cm deep.

2. Cutting selection: First, select good mother trees. Generally speaking, the older the tree, the more difficult it is to root. Therefore, cuttings should be collected from young mother branches; it is best to use semi-lignified branches of the current year to increase the survival rate. After collection, the cuttings should be placed in a cool, damp place or wrapped in moist material to prevent water loss, and cut into cuttings. Do this by collecting, cutting and planting in immediate succession. The cutting length should be 5 to 20 cm, with 2 to 3 leaves retained. The upper end of the cutting should be cut flat 2 cm above a bud, and the lower end should be cut at a slant. Cutting methods include single-bud cuttings, double-bud cuttings and multi-bud cuttings. Single-bud cutting: cut the cutting into one bud node, keeping the leaf at the upper bud and removing the leaf at the lower bud. Double-bud cutting: cut the cutting into two bud nodes, keeping the leaves of two buds at the upper part and removing the leaf at the lower bud. Multi-bud cutting: cut the cutting into three bud nodes, keeping three bud leaves on the two upper bud nodes and removing the leaf at the lower bud.

3. Cutting method: Softwood cuttings should be taken when new shoot growth is slow, that is, from June to September, and preferably during the rainy season. This is because the high air humidity in the rainy season favors rooting of the cuttings. Single-bud cuttings should generally be inserted to one-half of the branch length, while double-bud and multi-bud cuttings should be inserted up to the upper leaves. Do not insert them too deep. The density should be such that the cuttings do not press against one another, and the base of the cuttings can be seen when viewed from above.

4. Strengthen management: Softwood cuttings require relatively high air humidity and suitable substrate moisture content, and appropriate shading is essential. Excessive sunlight will raise the bed temperature and lower the humidity, which is not conducive to the survival of the cuttings. Reed curtains, bamboo curtains or shade nets can be used for shading, generally at a shading intensity of about 70%. The temperature of the seedbed substrate should be kept within the range of 22°C to 28°C; under this temperature condition, the cuttings root most easily.

How to Increase the Cutting Survival Rate of Golden Privet

The golden leaf color of golden privet and its tolerance to pruning have led to its widespread use in landscaping. To propagate golden privet rapidly in large quantities, increasing its cutting survival rate is crucial. The following is a summary of years of cutting experience for your reference.

Use new shoots of two-year-old golden privet; it is best to cut the lignified part into cuttings about 15 cm long. Remove all the lower leaves and keep 2 to 3 leaves at the upper part. Make a flat cut at the upper incision 1 cm from the upper bud, and make a slanted cut on the back side of the bud at the lower incision to form a horseshoe shape. Use coarse sandy soil as the cutting substrate, disinfect it with 0.5% potassium permanganate solution for 1 day, then use it for cuttings. Before inserting, first make holes with a wooden stick slightly thicker than the cutting; after inserting, press lightly to firm it. The cutting density should be such that the leaves do not touch one another and are evenly distributed. After spraying thoroughly with clean water, cover with plastic film, press down half of it firmly with soil, and press the rest tightly with bricks so that water can be sprayed. Then shade with reed curtains. Before rooting, spray water twice a day, from 10:00 to 11:00 in the morning and from 13:00 to 14:00 in the afternoon, to lower the temperature and retain moisture, keeping the temperature inside the shed at 20°C to 30°C and the relative humidity above 95%. Ventilate appropriately at noon every day. In summer, to prevent rot, spray 800 times carbendazim 3 days after cutting, and spray once more after 10 days. About 21 days after cutting, ventilate slightly at both ends for 2 days, then the plastic film can be removed in the morning and evening, with shading by reed curtains at noon. Pay attention to spraying more water, and remove it all after 3 days. After hardening the seedlings for 4 to 5 days, transplanting can be carried out on cloudy days or in the evening. Immediately after planting, water thoroughly once, and water again after 3 days. The survival rate can reach 100%. In winter, a small arched shed is needed for overwintering.

Special attention should be paid to the fact that the cutting survival rate is greatly related to the cutting substrate, the concentration of rooting powder, the degree of lignification of the cuttings and the cutting time: coarse sandy soil as the cutting substrate gives a higher rooting rate than fine sandy soil; dipping in a one-thousandth solution of rooting powder gives a higher rooting rate than lower concentrations; lignified cuttings give a higher rooting rate than semi-lignified ones; and summer cuttings give a higher rooting rate than autumn cuttings.