Detailed Explanation of Key Points for High-Yield Cultivation Techniques of Forsythia

Forsythia (Forsythia suspensa), also known as Lianke, Qingqiao, Luoqiao, Huanghuatiao, Lianzhao, Huangqidan, etc. The fruit is used as medicine, and has the effects of clearing heat and detoxifying, dissipating nodules and reducing swelling, and promoting urination and expelling stones. It mainly treats wind-heat common cold, carbuncles and swellings, sores and boils, erysipelas, cervical lymphatic tuberculosis, urinary tract infections, acute and chronic tonsillitis, allergic purpura, skin eruptions and rashes, acute nephritis, renal tuberculosis and other conditions. Modern pharmacological research shows that forsythol contained in the forsythia shell has an inhibitory effect on Bacillus dysenteriae, Bacillus typhi, Bacillus tuberculosis, Diplococcus pneumoniae and Staphylococcus aureus. Oleanolic acid contained in the forsythia shell has cardiotonic and diuretic effects; forsythia decoction has an antiemetic effect. The main producing areas include Shaanxi, Shanxi, Hebei, Henan, Gansu, Ningxia, Shandong, Sichuan, Yunnan and other provinces and regions.

Morphological characteristics: It is a deciduous shrub of the genus Forsythia in the family Oleaceae, 2-3 m tall. Stems are clustered, branches are slender, spreading or drooping, and rooting when touching the ground. Branchlets are slightly four-angled, with hollow internodes, and solid pith only at the nodes. The surface is light brown, with obvious lenticels. Leaves are simple, opposite, or occasionally with 3 leaflets; leaf blades are ovate, broadly ovate, or elliptic-ovate, 1.5-4.5 cm long and 1.2-2.5 cm wide, hairless, with acute or obtuse apex, rounded or broadly cuneate base, and irregularly serrate margins. Flowers are one to several, axillary; the calyx base is united into a tube, with the upper part deeply 4-cleft; the corolla is yellow, about 3 cm in diameter, with 4 ovate lobes, and the corolla tube often has orange-red stripes. Stamens are 2, inserted at the base of the corolla; the style is slender, and the stigma is 2-cleft. The capsule is narrowly ovate, slightly flattened, woody, with scattered warty dots on the outside, and when mature it splits into two like a bird's beak. Seeds are numerous, brown, flattened, with a thin wing on one side, and skewed.

I. Growth habits: Forsythia prefers a warm and dry environment with sufficient sunlight; it is cold-resistant, drought-resistant, and averse to waterlogging. It has no strict requirements for soil, but sandy soil with deep, loose, fertile layers rich in organic matter is best.

II. Land preparation and fertilization: Choose a field with high terrain and good drainage, or a wind-sheltered sunny hillside, and plow and harrow carefully. In combination with land preparation, apply sufficient base fertilizer: 3000 kg of farmyard manure, 20 kg of urea, and 50 kg of phosphate and potassium fertilizer per mu. Then make high beds 1.5 m wide. Wait for sowing.

III. Sowing: Forsythia is propagated by seed and by cuttings. It can also be propagated by division and layering. The sowing period is spring sowing. Seed propagation: Before sowing, first use a drill to open shallow furrows with a row spacing of 20 cm on the prepared bed surface, then evenly scatter the seeds into the furrows, rake smooth so that the soil covers the seeds, and water to preserve soil moisture to facilitate seedling emergence. The sowing rate is 2.5 kg per mu. After full emergence, pay attention to field management; after 1 year of cultivation, it can be transplanted. Cutting propagation: Select robust 1-2 year old branches, cut them into 30 cm long cuttings; each segment must have 3 nodes, and the lower end is cut into a horse-ear-shaped slant. Bundle every 50 cuttings into one bundle, soak in 500 ppm rooting powder solution for 10 seconds, take them out and let them dry slightly, then insert them into the prepared bed surface at a row spacing of 30 x 10 cm. Water to preserve soil moisture to facilitate survival. After survival, strengthen field management; after 1 year of cultivation, it can be transplanted. Division propagation: In March-April, press the drooping and bent mother plant into the soil, and wound it at the point of entry into the soil to make it root and form a seedling. In early spring, cut it off from the mother plant and plant it separately. Transplanting: Plant forsythia seedlings on the prepared bed surface at a row spacing of 2 x 1.5 m (222 plants per mu), and water to preserve soil moisture to facilitate survival. Forsythia is a self-incompatible plant on the same plant, and the seed-setting rate from self-pollination is extremely low, about 4%. If long-styled or short-styled forsythia is cultivated alone, none will set fruit. Therefore, when planting, plants with long and short styles must be planted alternately in order to bloom and bear fruit. This is the key to increasing yield.

IV. Field management: After forsythia seedlings emerge or after transplanting survives, attention should be paid to intertillage and weeding. Water promptly in dry weather, and drain immediately in rainy weather. In combination with intertillage and weeding, apply fertilizer once each year: apply 15 kg of urea, 50 kg of phosphate and potassium fertilizer, and 3000 kg of farmyard manure per mu. During the growth of forsythia, shaping and pruning should also be carried out, training the forsythia into a low, flat, short crown with an open center and rounded exterior, ventilated and light-transmitting. A natural open-center tree shape with sparse branchlets. At the same time, every winter, cut off dead branches, overlapping branches, crossing branches, weak branches, water sprouts, and diseased and pest-damaged branches. During the growing season, appropriate thinning and heading back should also be carried out.

V. Pest and disease control: For stem borers, use a syringe to inject phoxim liquid into the insect holes to kill them. Diseases should be controlled by conventional methods.

VI. Harvesting and processing: Forsythia blooms and bears fruit 3-4 years after transplanting. Generally around Frost's Descent, when the fruit changes from green to yellow, it can be harvested. The harvested fruit is sun-dried, and impurities and seeds are removed to make the commercial product Huangqiao. Qingqiao is made from immature green fruits harvested from August to September, boiled in water or steamed in a steamer for half an hour, and then sun-dried. The seeds are called forsythia core.