What are the propagation methods for black pine? Learn how to grow seedlings in one article

Black pine is an evergreen tree with grayish-black bark, dark green needles, and a crown that is broadly conical or umbrella-shaped. It can be planted in roads and courtyards for landscaping, and can also be grown as a small potted plant for ornamental viewing. What are the propagation methods for black pine?

1. Propagation methods for black pine

1. Seed propagation:

① Collecting seeds: After harvesting the mature fruits of black pine, place them in a ventilated spot to dry in the sun, then rub off the outer fruit skin to thresh the seeds and store them in sand.

② Choosing the sowing site: For sowing and raising black pine seedlings, choose soil that is soft, breathable, and well-draining for sowing. First disinfect the land with ferrous sulfate, then apply fertilizer to the chosen land and deep-plow it once.

③ Seed treatment: Before sowing, first soak the black pine seeds in potassium permanganate for about 2 hours, then soak them in warm water until the water temperature becomes room temperature; the next day, take them out and spread them in a ventilated place to dry. The seeds need to be sprinkled with water once a day, and they can be sown after a week; the seeds can be mixed evenly with soil before sowing, which will give a very high seedling emergence rate, and one-year-old black pine seedlings can grow to a height of about fifteen cm.

2. Cutting propagation:

① Choosing branches: Before cutting, choose one-year-old fresh branches to cut; you can also choose young branches from older trees with a relatively long tree age.

② Branch treatment: Soak the selected branches in an indolebutyric acid (IBA) solution for 12 hours. Branches that have been soaked have a very high seedling emergence rate when cut and are easy to root.

2. Care of black pine

1. Black pine is a cold-tolerant and drought-tolerant plant that can be cared for year-round on a courtyard or balcony. Sufficient sunlight and a ventilated environment allow black pine to grow and develop well. Small black pine bonsai are not easy to keep warm and protect from the sun, so pay attention to preventing freezing in winter and avoid exposure to the sun in summer.

2. Black pine is drought-tolerant but not waterlogging-tolerant. Watering should be moderate, following the principle of watering when dry and stopping when wet. When the potting soil turns slightly white, or when you touch it with your hand and feel that the soil has no moisture, you can water it thoroughly. However, water must not accumulate. In summer high temperatures, you can often spray water on the leaves.

3. Black pine is tolerant of poor soil. During its growth period, it is enough to appropriately apply 1-2 times of decomposed dilute cake fertilizer water.

4. To maintain the beautiful and elegant tree shape of black pine bonsai, proper pruning is necessary. During the growing period, pruning is mainly by pinching buds, 3-4 times per year. When new buds have elongated but have not yet produced needles, about 1/2 of each terminal bud can be removed. For bonsai that do not need to grow more branches, all terminal buds can be removed. For branches that affect the beauty of the tree shape, pruning can be done during the dormant period.

5. Black pine only needs to be repotted once every 3-5 years, generally preferably in February-March. When repotting, it is best to keep the potting soil intact to avoid damaging the root system. When changing the soil, remember to remove half of the old soil and then add new soil. When changing pots, if the original plant is still growing, you can appropriately switch to a larger flower pot; if it is an old stump, there is no need to change it. When repotting, take the opportunity to prune old roots, diseased roots, residual roots, rotten roots, etc. among the root system, disinfect and kill insects, and repot after the wounds have dried.

6. The most common diseases of black pine bonsai are leaf rust, needle cast disease, pine gall disease, and twisting branch disease. For example, for pine needle rust and pine gall disease, you can spray 65% wettable ferbam; for needle cast disease, spray 0.5 lime sulfur mixture. For pests such as aphids, scale insects, and red spider mites, spraying insecticide is enough.

Black pine is easy to keep alive and easy to grow, and is generally propagated mainly by sexual reproduction for planting in batches.