What are the propagation methods for boxwood? A detailed explanation of the latest practical techniques
Boxwood is also called boxwood wood, Chinese boxwood, common box, etc. It is mainly produced in Shaanxi, Gansu, Hubei, Sichuan, Guizhou, Guangxi, Guangdong, Jiangxi, Zhejiang, Anhui, Jiangsu, Shandong and other places in China. The main propagation methods are seed propagation and cutting propagation. Let's take a look at the propagation methods of boxwood together!
The growing environment of boxwood
Boxwood mostly grows in high mountains and steep cliffs, as well as in mountainous and rocky places. It is shade-tolerant and likes a warm, humid climate and loose, fertile soil. It can grow in acidic, neutral and alkaline soils. It has a well-developed root system, strong sprouting ability, weak cold tolerance, and resistance to pollution.
Seed propagation of boxwood
1. Seedbed: In early September, choose loose, fertile, well-drained sandy soil as the sowing site, apply base fertilizer (organic fertilizer) and mix in insecticides and fungicides such as carbendazim, then deeply plow and level it to make a seedbed.
2. Sowing rate: The sowing rate is 50-60 grams per square meter. Mix the seeds with an appropriate amount of sand, then evenly scatter them on the seedbed, cover with fine soil 1-1.5 mm, and cover with a layer of straw curtain to retain moisture.
3. Post-sowing management: After sowing, the seeds only grow radicles in the same year and do not germinate. To prevent freezing damage, from mid-to-late November before the soil freezes, cover the straw curtain with 5-8 cm of soil. In mid-to-late March of an average year, remove the straw curtain and covering soil, and build a plastic arch shed on the seedbed, with the temperature controlled at 25-30°C. After about 20 days, the embryos grow out of the soil surface. After that, keep the temperature inside the shed between 20-25°C, and water appropriately. In late April, when the temperature is stable, remove the plastic arch shed. During the seedling stage, weed and loosen the soil, water in time, spray 2% potassium dihydrogen phosphate solution several times for foliar topdressing, and promptly prevent and control pests and diseases.
Cutting propagation of boxwood
1. Seedbed: For the cutting seedbed, choose a plot with high terrain, deep soil layer, loose soil, and good drainage and irrigation. After removing grass roots and stones, make a high bed about 1-1.2 m wide, and drench with 10% imidacloprid at 1000 times plus 5% mancozeb at 1500 times to eliminate underground pests and harmful pathogens. After leveling the seedbed, pat it flat with a shovel, pour on 10% decomposed dilute human manure, and then spread a layer of sieved burnt mud ash or yellow soil on the bed surface, about 5 cm thick.
2. Cuttings: Boxwood can be propagated by cuttings at any time, but using tender branches grown in the current year as cuttings in summer gives a high survival rate. Select excellent current-year lignified or semi-lignified branches as cuttings. After collecting the cuttings, cut them in a cool, wind-sheltered place, and use sharp knives or scissors. When cutting, for branches that have already grown small branches at the nodes, cut 0.5 cm above and below the node, then split the stem node into two halves according to the position where the small branch grows, and insert the two branches separately. For branches that have not grown small branches, be sure to keep 2 nodes, cut the upper end into a flat cut 1 cm above the bud, and cut the lower end into a horseshoe shape or flat cut 0.5 cm from the bud.
3. Insertion: Cuttings should be inserted shallowly rather than deeply. For small branch division cuttings, place the flat cut downward, with a depth of 1 cm into the soil for the mother plant as suitable. For large branch cuttings, insert the next stem node 1 cm into the soil. Insert the cuttings at an angle of about 45 degrees to the ground. Shallow and slanted insertion helps the cuttings take root and survive earlier. After insertion, compact the soil around the cuttings and immediately water thoroughly once so that the lower part of the cuttings fits closely with the soil. The row spacing for cuttings is generally 12-15 cm, and the plant spacing is 6-8 cm. When inserting cuttings, do not leave too many leaves on the cuttings, but do not cut them all off either. The lower leaves can all be cut off together with the petioles, and 2 leaves should be kept on the upper part. Then, depending on leaf size, cut each leaf by 1/2 to 2/3 to reduce excessive consumption of water and nutrients.
4. Management: After boxwood cuttings are inserted, a shade frame should be built to reduce transpiration and direct sunlight on the seedbed. When cutting in early spring or late autumn, plastic film should also be added to prevent winter damage. After cutting, water frequently to keep the seedbed soil moist, so that the surface soil of the seedbed does not noticeably turn white. Topdressing for cuttings can be done together with watering, or potassium dihydrogen phosphate plus urea can be sprayed on the leaves. Weeding must be done very carefully, without bumping the cuttings.
5. Transplanting: Roots can develop in about one month, and after about 2 months they can be transplanted into the nursery for cultivation. In the first year, proper shade is needed in summer and autumn. From the second year onward, general management is sufficient. During the peak growth period, apply nitrogen fertilizer water 1-2 times per month, and stop fertilizing after autumn. Seedlings cultivated for 2-3 years can be planted in small pots, and 4-5 year old seedlings can be used for flowerbed edging or ground planting.