Seed propagation techniques and key maintenance and management points for Virginia creeper
Virginia creeper, also known as five-leaf ivy, belongs to the genus Parthenocissus in the grape family (Vitaceae). In autumn, the “creeper” truly lives up to its name: different leaves accumulate different amounts of anthocyanins, and together with differences in carotenoid content, from a distance it indeed looks like brocade woven from three colored threads of red, yellow and green. Below, we introduce the seed propagation techniques and key maintenance and management points for Virginia creeper.
I. Seed propagation techniques for Virginia creeper
1. Seed treatment
From late March to early April of the same year, take out the seeds, warm them to room temperature, soak the seeds in warm water at 35-40°C for 24h, then take them out and soak them in a 5‰ potassium permanganate solution for 15-30min, rinse with clean water 3-4 times, mix in clean moist river sand at a ratio of 1:3, and place them in a nursery cellar for low-temperature moist cold storage. From late April to early May, take them out for germination promotion, and sow when 30% of the seeds have cracked open and shown white.
2. Land preparation and bed making
Choose a flat plot with good drainage and sandy loam soil as the nursery site, and prepare the land with a rotary tiller to ensure the soil is loose. Use raised-bed seedling cultivation, with the seedbed 10-15cm high, 1-1.2m wide, and 10-20m long, with a path width of 50cm as appropriate, and apply basal fertilizer diammonium phosphate at 10gm-2.
3. Sowing
Sow by drilling in furrows, with a furrow depth of 2-3cm and a furrow spacing of 20cm. The sowing rate per 667m2 is 1.71kg, that is, 90-100 seeds m-2 or 18-20 seeds per row. After sowing is completed, compact the seedbed, cover with a thin layer of larch pine needles, and then water thoroughly.
4. Tending and management
Water at appropriate times, generally once every 2-3d. Within 3d after sowing, spray a herbicide once; the agent type and dosage are 24% oxyfluorfen 20mL mixed with 5% quizalofop-p-ethyl emulsifiable concentrate 50mL, diluted in 50kg of water, and sprayed on the seedbed. About 20d later, the seedlings emerge completely, with a relatively high emergence rate that can reach more than 90%, and relatively large growth, with an average ground diameter of up to 0.37cm and the main vine reaching more than 0.9m.
The seedlings can overwinter in the open field. After leaf fall and before the soil freezes, water the seedbed thoroughly once to prevent the seedlings from drying out due to lack of water. They can also be graded and placed in a cellar for heeled-in storage.
II. Key maintenance and management points for Virginia creeper
1. Pre-dig the storage pit. Before winter, choose a wind-sheltered, sunny spot and dig a storage pit; the length and width can be arbitrary, but the depth must be more than 100 centimeters, in order to create a suitable temperature (3°C to 10°C) and moist environment, which helps the cuttings complete rooting and sprouting during storage.
2. Cut cuttings and bundle them. After late October, select thick, disease-free branches, and cut them from bottom to top into cuttings 20 to 25 centimeters long, each with 3 to 5 buds, noting that the lowest cut should be 0.5 centimeters below the basal bud to promote rooting. Then, following the principle of consistent polarity, level the bases of the cuttings, sort them into bundles, and preferably count and tie them firmly to facilitate subsequent operations.
3. Bury and cover with soil. After the cuttings are cut and bundled, it is best to bury them in the pit the same day they are cut. When burying, pay attention to the polarity of the cuttings, and be sure to keep the bases facing downward. Bundled cuttings can be placed upright side by side, and then moist clean soil is backfilled over the tops of the cuttings, about 5 centimeters thick, so that the tops of the cuttings are not exposed. Afterward, according to the gradual decrease in temperature, cover with soil in stages, and before the arrival of the lowest temperatures in January, the final cumulative soil cover should reach 50 to 70 centimeters thick.
4. Plant at the appropriate time the following spring. After 5 months of burial, by March and April of the following spring, the cuttings have spontaneously produced milky-white young shoots and multiple white roots. However, at this time the average open-field soil temperature is still lower than the pit storage temperature, which is unfavorable for root growth. In addition, the average last frost date has not yet passed, which is unfavorable for the milky shoots to turn green when exposed to light. Therefore, the planting period should not be too early; otherwise, low temperatures may cause root death and shoot regression, which is unfavorable for survival. Specifically, late April to early May is most suitable. Of course, when planting at the appropriate time, reducing intermediate delays, trying to plant immediately after taking them out, not damaging the milky shoots and white roots, and watering promptly after planting are also not to be ignored. In this way, one month after planting, one will see a scene of fresh green with expanded leaves and extending vines, and by autumn of that year it can develop quite considerably.
5. Five-leaf ivy has strong adaptability, being both cold-tolerant (it can overwinter in the open field in Northeast China) and heat-tolerant (it also grows well in Guangdong). Five-leaf ivy is tolerant of poor soil and drought, shade-tolerant, and strongly resistant, and its cultivation and management are relatively extensive. After winter begins, thin out dead branches, and apply light fertilizer in early spring, which can promote luxuriant branches and leaves. Nanjing is a continental climate area, so it should be planted at the base of north walls and east walls, and planted tilted toward the climbing support. To prevent the base of the vines from becoming bare too early and to facilitate attachment, heavy pruning should be carried out more often.