Key Technical Points for Introduction and Propagation of Japanese New Lilium formosanum

I. Characteristics and Traits

In 2004, New Lilium formosanum seeds were introduced from Japan for planting. The plant height reaches 40--70 cm, the flowers are pure white, trumpet-shaped, with 1 terminal flower. After flowering and bulb development, it takes only about 8 months from sowing to flowering. The propagation coefficient is high, it is pathogen-free, and it possesses some excellent traits of Lilium formosanum. After more than two years of trial planting and promotion at the Daheng Science and Technology Park and the Taqian Lily Base in Nanping City, the suitable sowing period for New Lilium formosanum is late September to mid-October, and flowers can be harvested 9 months after sowing. New Lilium formosanum is a hybrid of Japan's Takasago Lily and Taiwan Lilium formosanum, with larger flowers, pure white color, and a rich fragrance. It is a high-temperature lily, prefers a warm and relatively humid environment, and dislikes dry cold and strong sunlight. The suitable growth temperature is 25-28°C during the day and 18-20°C at night. The natural flowering period under cultivation is April--May, and forced cultivation can achieve year-round flowering. It is one of the excellent cut flower varieties.

II. Cultivation Points

1. Sowing: New Lilium formosanum prefers sandy, slightly acidic soil. Unlike other lilies that prefer fertilizer, well-rotted organic fertilizer can be applied generously when raising seedlings. When sowing, the seedbed can use spot sowing with a row spacing of 10 cm and a plant spacing of 3 cm. After spot sowing, cover with 0.5 cm of sandy soil. The optimum germination temperature for New Lilium formosanum is 15-20°C. After sowing, the most important thing is to maintain moisture. If conditions are suitable, seedlings can emerge in 15 days. At about 30 days, when the seedlings have 2-3 leaves, they are suitable for transplanting.

2. Transplanting and management: After the first true leaf unfolds, spray with acidic amino acid compound fertilizer. When the seedlings grow to 5 true leaves, transplant them. When transplanting, raised bed cultivation must be used, with sufficient organic fertilizer applied, at a spacing of 12 cm x 12 cm, and water thoroughly after transplanting. If the leaves turn yellow after seedling recovery, foliar spray with 1:500 ferrous sulfate. When the plant height reaches about 20 cm, pay attention to adding netting to prevent lodging. New Lilium formosanum prefers sufficient sunlight but is not tolerant of high temperatures. Prolonged high temperatures above 30°C will affect its growth and development. In hot summer temperatures, shade netting should be set up in a timely manner. At the hottest noon, water should be sprayed on the leaves to cool them down. In summer, intertillage and soil loosening should be carried out along with weeding.

3. Harvest: Generally, seedling plants sown in January--February begin to bloom successively around September. Because it is seedling cultivation, the flowering period is not very uniform, roughly lasting about 2 months. When the flower buds turn slightly white, they can be cut and marketed.

III. Flowering Period Regulation

In the production of fresh cut lilies, reasonable scheduling to ensure flowers for holidays and balanced supply during ordinary times can improve the economic benefits of flower growing. The measures generally adopted for production period regulation include:

1. Variety combination: There are many varieties of cut lilies. According to the length of the production period of Dutch lilies, they can be divided into early-, mid-, and late-flowering types, and should be appropriately matched when sowing.

2. Sowing in batches: Because the flowering period is comprehensively affected by various climatic factors such as temperature, sunshine, and light intensity, the climate conditions of different seasons should be considered when arranging the planting period. Staged sowing is adopted, generally sowing in batches about every 15 days, and the sowing amount should be predicted and arranged in combination with climate condition changes, which can ensure balanced flower production.

3. Increasing temperature and supplementing light to promote flowering: In winter and spring, if there is continuous low-temperature and rainy weather, in order to promote earlier flowering, artificial lighting and electric heating can be used to raise the temperature of the soil and air. In the greenhouse, one 400-watt incandescent lamp can be hung per 8-10 sq m of seedbed. Supplementing light for 6-8 hours per day can prevent blind flowers and promote earlier flowering.

4. Use of silver thiosulfate (STS): STS treatment once, or spraying 0.5 mmol/L STS once every two weeks, can solve the phenomena of bud drop and drying in lilies, and can promote flower bud development and maintain the flowering period.

5. Cold storage and preservation of cut flowers: If due to abnormal climate reasons a large number of lilies bloom earlier while market demand is not strong, then cold storage measures are adopted. Lily cut flowers can be stored at 0-1°C for 2-3 weeks.

IV. Propagation

The first year is seedling cultivation. From the young seedling stage to the beginning of stem elongation, the nutrients absorbed by the roots are almost entirely supplied to the aboveground part, and the underground bulb basically stops growing. Only after cutting flowers does the bulb begin to enlarge. After cutting flowers, the aboveground part should be well managed in order to nourish the bulb. Only after the aboveground part naturally dies can the seed bulbs be dug. When digging the seed bulbs, choose clear and fine weather, and be careful not to damage the outer scales when digging. Remove rotten and damaged scales in a timely manner. After digging out, store in a ventilated and cool place. The dormancy level of New Lilium formosanum is very shallow, and it can be planted at any time as needed in plastic tunnels and greenhouses; even if planted immediately, it can germinate. For cold storage, first grade and disinfect the bulbs, then put them into plastic boxes, fill with sawdust or sand, and store in a cold storage at 0--2°C.