What are the methods for cultivating strong Ophiopogon japonicus seedlings?
Ophiopogon japonicus, also known as dwarf lilyturf, snakebeard grass, maidong, and cundong, is a perennial evergreen herbaceous plant of the genus Ophiopogon in the family Liliaceae. Its fibrous roots are relatively thick and strong, and the tip or middle of the roots often swells into a spindle-shaped fleshy tuber. The tuberous roots are used as medicine. The techniques for cultivating strong Ophiopogon japonicus seedlings are introduced below:
1. Seed collection: The seed maturation period of Ophiopogon japonicus is around the “Start of Summer” in May. Seeds produced three or four years after the seedlings are transplanted are of good quality and have a high germination rate. When the seed shell turns yellow and the seeds become yellow-brown, and when pressing the fleshy part with a fingernail shows a petal-like form without water bubbles, the seeds are ripe. When harvesting, choose a sunny day with no dew, gently cut off the seed stalk with scissors, put the seeds into a cloth bag, and carry them home. Place them indoors on a ventilated and dry winnowing basket or bamboo mat for 1~2 days, then gently rub out the seeds by hand and remove the fruit skin, branches, leaves and other residue. Spread the threshed seeds on a winnowing basket or bamboo mat lined with plastic film to cool, at a thickness of about 1 cm, turning them 1~2 times a day, and leave them for 6~10 days. Once the seeds have all turned yellow-brown and no longer stick to the hand when touched, store them.
2. Seed storage: After harvest, Ophiopogon japonicus seeds enter dormancy. Under natural conditions, the dormancy period lasts as long as 6 months, and only after the dormancy period can sowing germinate, so safe storage is required before sowing and raising seedlings. The physiological characteristics of Ophiopogon japonicus seeds are that they prefer shade, moisture and low temperature, and fear drying out, sun exposure and waterlogging. If too dry, they cannot germinate. Storage methods:
1. Mixed mud and sand storage method: Take mud and sand from Ophiopogon japonicus fields and sieve out small stones, grass roots and debris. For dryness and moisture, it is suitable if it forms a ball when squeezed by hand and breaks apart when released. The weight ratio of seeds to mud and sand is 1:3. After mixing the seeds with mud and sand evenly, store them in a wooden box or a large-mouthed ceramic jar, with a layer of plastic film at the bottom, covering the surface with 5 cm of sand, and then covering with a layer of palm leaves. Alternatively, build a seed storage chamber against an indoor wall corner with a width and height of 50 cm each and a length as needed. In hot seasons, open the windows at any time for ventilation. When the stored sand is too dry, spray water appropriately to maintain moisture. Be careful not to let chickens, dogs, cats or rats defecate or urinate on the stored sand, which would cause the seeds to rot.
2. Clean seed bag storage method: Put the seeds in hemp bags or cloth bags, filling one third of the bag, and seal the bag mouth tightly. Then select a plot outdoors with a slope of about 15 degrees and dig a rectangular pit 15 cm deep and 1 m wide, with length as needed. Place a layer of river sand 2~3 cm thick at the bottom of the pit, then place the seed bags in the pit one by one, press the seed bags flat so that the seed thickness in the bags is 3~5 cm, cover the bag surface with about 5~8 cm of fine soil, dig a drainage ditch 20 cm deep around the seed storage pit, and finally build a shade shed with bamboo, wood or plastic film to maintain moisture and avoid sun exposure. The shed height is about 1 m, and the surroundings are tightly enclosed with fencing.
3. Land selection and preparation: For seedling land, gentle-slope virgin wasteland is best, because virgin wasteland has relatively fertile soil, no disease contamination, and fewer weeds. Cultivated land tends to grow weeds and is not suitable as seedling land. September to October is the best time for land preparation and seedling raising. Land preparation method: cut down weeds and trees and burn them to ash for later use, dig out tree stumps and grass roots, pick up stones and residual branches and fallen leaves, use a rake or hoe to shallowly turn the topsoil to a depth of 10 cm, rake the soil fine and level it, make beds along the slope with a width of 1.3 m and length as needed, and dig drainage ditches well.
4. Build a shade shed: Along the center line of the back of the bed, drive a wooden stake every 2 m, with a stake height of 1.6 m. Make the upper end of the wooden stake into a “y”-shaped bend, place tied bamboo and wooden branches to build a shade shed, or use black plastic shade netting to build the shed for a better effect.
5. Sow at the right time: October to November is the best sowing time. Each mu of seedbed uses 2~3 kg of clean seeds and can cultivate 250,000~400,000 strong seedlings. Sowing method: mix the seeds with fine soil at 1:3 and stir evenly, then sow them one by one on the bed. To achieve uniform density, sow repeatedly in 2~3 rounds, then dig fine soil from the bed ditch and mix it with an appropriate amount of plant ash, scatter it to cover the bed surface at a thickness of about 1 cm, just enough to cover the seeds, and then build the shade shed.
6. Seedbed management: To cultivate high-quality strong seedlings, the following management measures must be carried out well:
1. Remove debris: After the seeds emerge, promptly clear away dead branches, fallen leaves and other residue on the seedbed so that the seedlings can grow smoothly.
2. Remove weeds: Some weeds grow together with the seedlings and compete with each other for fertilizer and light, so they must be removed in time. Generally, weed once each in March, June and August. When weeding, protect the weak seedlings, do not damage the seedlings when pulling weeds, press back any loosened seedlings by hand, and immediately spray water once to protect the seedlings, so as to avoid the leaves losing water, turning yellow and stopping growth.
3. Fertilize to promote seedlings: When Ophiopogon japonicus leaves grow 3~5 leaves, begin applying topdressing. Generally apply once each in April, July and September. Method: For the first application, use 50~80 kg per mu of plant ash mixed with an appropriate amount of oil cake and dried chicken manure fertilizer, mix with an appropriate amount of fine soil, and broadcast on a sunny day. For the second application, apply 15~20 loads per mu of thoroughly decomposed human and livestock manure water with residue removed, adding 100 g of urea per load, and splash it on. For the third application, broadcast 3~5 kg of urea per mu, or spray 2-3 kg of monopotassium phosphate on the leaves on a cloudy day with no dew. After application, promptly use a bamboo branch broom to brush the urea off the seedling leaves to prevent burning the leaves.
4. Thin seedlings at the right time: Thinning seedlings is an important measure for cultivating strong seedlings. Some seedlings are too dense and crowded, competing with each other for fertilizer and light, causing the young seedlings to turn yellow and die. Thinning methods: First, when pulling out weeds, pull out the overly dense weak seedlings with 3-5 leaves and transplant them evenly into sparser gaps, so that the seedling spacing reaches 1 plant per 1 square cm. Second, take out the strong and leave the weak, and take out seedlings in batches. For seedlings 1-1.5 years old, transplant the strong seedlings with 6-14 leaves first, and leave the weak and small seedlings in the ground to continue cultivation. After each batch of seedlings is taken out, apply water and fertilizer once in time until all are taken out.