A Detailed Guide to the Planting Methods and Key Technical Points for the Flame Vine

The flame vine (Pyrostegia venusta (Ker-Gawl.) Miers), also known as the yellow eel vine, is a vine in the family Bignoniaceae and the genus Pyrostegia, with 3-forked filamentous tendrils. Leaves are opposite; the stamens are inserted at the middle of the corolla tube, with filamentous filaments and divergent anthers. The ovary is cylindrical and densely covered with fine soft hairs; the style is slender, the stigma is tongue-shaped and flattened, and both the style and filaments extend beyond the corolla tube. The fruit valves are leathery and boat-shaped, containing multiple rows of seeds; the seeds are winged and membranous. The flowering period is long. It is native to Brazil in South America and has been widely cultivated in tropical Asia as an ornamental climbing plant for garden trellises and pergolas. It is often planted around garden buildings and climbs onto arbors; in early summer, the red-orange flowers hang in dense clusters like strings of firecrackers, which is why it is called the flame vine.

I. Introduction to the Growing Habits of the Flame Vine

The flame vine prefers a sunny environment and fertile, moist, acidic soil. It grows rapidly. In South China, it can remain evergreen and overwinter outdoors. Because the tendrils mostly grow at the stem nodes of the upper branches and vines, the whole plant can attach itself to other objects for support as it grows. It is cultivated in Guangdong (Guangzhou), Hainan, Guangxi, Fujian, Taiwan, China, Yunnan (Kunming, Xishuangbanna) and other places in China.

II. Introduction to the Propagation Methods of the Flame Vine

1. Layering: Layering mainly uses vines that have trailed on the ground; the bark at the leaf axils is wounded and then covered with soil. It can be done in spring, autumn or summer, with summer being the most suitable. Roots form after 20 to 30 days, and after one and a half months it can be cut off as a new plant, which can bloom in the same year; it is mostly grown in pots. Alternatively, it can be layered directly into a container without being moved to a nursery bed for seedling cultivation.

2. Cuttings: For cuttings, in mid-to-late March, select 1-year-old robust branches as cuttings and insert them into a moist sand bed with misting to keep them humid. When the air humidity is stable at around 20°C, roots form about 25 days after insertion, and the survival rate can reach 70%. After about one and a half months, they can be moved to a nursery for cultivation. One-year-old seedlings can be planted out, will bloom the following year, and can form a green landscape by the third year. Old stems can also be used for cuttings inserted into fertile sandy loam soil and kept in partial shade; roots begin to form after about 50 to 60 days, and in that year the shoots and leaves are allowed to grow freely.

III. Introduction to the Cultivation Methods of the Flame Vine

1. Soil: The flame vine is not demanding about soil, but it grows more vigorously when cultivated in fertile soil rich in organic matter, well drained and with a deep soil layer. For the growing medium, mainly use leaf mold, garden soil, mountain soil, etc., and apply an appropriate amount of decomposed compost, soybean cake, bone meal and other organic fertilizers as a base fertilizer.

2. Watering: Water according to the principle of watering when dry and stopping when wet; never allow water to accumulate in the pot. In summer, when temperatures are high, watering should be sufficient, and at the same time water should be sprinkled on the ground near the flower pot to increase air humidity. In autumn, the flower bud differentiation stage begins; at this time watering should be appropriately reduced in order to control vegetative growth and promote flower bud differentiation.

3. Temperature: The flame vine is not cold tolerant; in northern regions it must be moved indoors to overwinter. During overwintering, place it in a spot indoors with ample sunlight, control watering, stop fertilizing, and keep the room temperature above 10°C.

4. Fertilizing: Fertilizing the flame vine should shift to being mainly phosphorus-based; during the growing season, generally apply a dilute liquid fertilizer combining nitrogen and phosphorus about once every 2 weeks. During the bud stage, apply a liquid fertilizer mainly based on nitrogen once to promote flowering and plant growth.

5. Pests and diseases: Common diseases of the flame vine are leaf spot and powdery mildew, which can be sprayed with a 1500-fold dilution of 50% carbendazim wettable powder. Pests include whiteflies and scale insects, which can be killed by spraying with a 1200-fold dilution of 40% omethoate emulsion.

6. Pinching: When the flame vine seedling has grown to about 70 cm tall, a trellis should be set up, its branches should be guided onto the trellis, and pinching should be carried out to encourage the growth of side branches so as to promote more flowering.

IV. Introduction to Precautions for Cultivating the Flame Vine

1. The flame vine grows quickly, blooms abundantly and has a long flowering period, so fertilizer and water must be sufficient. During the growing period, apply a top dressing once a month; the top dressing should preferably be decomposed dilute soybean cake water or compound chemical fertilizer to promote luxuriant branches and leaves and flowers all over the branches.

2. When planting the flame vine, keep the soil moist. The frequency of watering should depend on the moisture condition of the soil. In hot summer, in addition to watering, spray water on the branches and leaves 2 to 3 times a day and sprinkle water on the surrounding ground to increase air humidity.

3. The flame vine produces tendrils and can climb upward by means of other objects. When growing it at home, to improve the ornamental effect, a large, deep flower pot can be used for planting. When the seedling reaches a certain height, set up a flower frame in the pot, tie its stems and vines to the frame, and take care to distribute them evenly, keeping it on a sunny balcony for care.

4. The flame vine can be planted in a large pot, with a flower frame set up on the balcony to let it climb upward. When the branches have grown to a certain height on the supporting object, the tips need to be pinched off to encourage new shoots to sprout so as to promote more flowering. Branches that have already flowered will not bloom again the following year, while newly grown branches must form buds; therefore, some old branches, weak branches, etc. should be pruned promptly to avoid consuming nutrients and affecting flowering the next year.

5. In winter, transplant the flame vine with soil into the middle of a lawn or an open area in front of a gate, and support it with bamboo to prevent lodging. It relies on tendrils for attachment as it grows; during the growing period, never turn the vines or break the tendrils, otherwise it will affect the absorption of water and nutrients, resulting in poor flowering or even no flowering.