Brain-boosting vegetable daylily: is it suitable for dryland cultivation? Varieties, planting and harvest times

Daylily, also known as golden needle vegetable, forget-sorrow grass, hemerocallis, etc., is a common perennial herbaceous plant of the Liliaceae family in China. Because of its high nutritional value and its effects of enriching the blood, boosting the brain and resisting aging, it is used as a health vegetable and is now grown in most regions. So is dryland suitable for growing daylily? Which varieties are good to grow? When are the planting and harvest times? How do you grow it?

I. Can it be grown on dryland?

Dryland can be used for planting, because daylily has a well-developed root system, tolerates poor soil and has strong adaptability. It can be grown on flat land or hillsides, and can grow normally in sandy loam and clay loam, as it is not demanding about soil. Daylily is a perennial crop and can be harvested continuously for more than 15 to 20 years after planting. To obtain high-yield, high-quality daylily, the most suitable sites are river flats, plateau fields, terraces, terraced fields and palm fields with deep soil, fertile soil, flat terrain, good drainage and a slope of less than 15°.

II. Variety selection

Existing daylily varieties such as Mengzihua, Siyuehua, Baihua, Jingzhouhua, Chonglihua and Dawuzui all have the characteristics of strong disease resistance and high yield. Generally, early- and late-maturing daylily varieties have lower yields, while mid-maturing varieties have higher yields. However, because the harvest period is long, early-, mid- and late-maturing varieties should be reasonably combined.

III. Planting techniques:

1. Raising strong seedlings

(1) Division propagation method

Division propagation is the most commonly used propagation method for daylily, and generally there are 2 ways:

① Dig out part of the plants from one side of the mother clump as planting stock, and let the rest continue to grow;

② Dig out the entire mother clump and replant it after division. When digging and dividing seedlings, damage the roots as little as possible, and dig, divide and plant in sequence. After the planting stock is dug out, shake off the soil, separate every 2 to 3 bud pieces into one clump or one plant, cut off the decayed roots, old roots and diseased roots growing from the lower part of the rhizome, keep only 1 to 2 layers of new roots, leaving about 10cm in length.

(2) Shortened stem block seedling-raising method

After the daylily harvest is completed, dig out the root plants, separate them by bud pieces, remove the dead leaves and hairy leaves around the shortened stem, keep leaves 3 to 5cm long, cut off the upper end, then cut the rhizome longitudinally from top to bottom into 2 pieces. If the rhizome is thick and strong, it can continue to be cut longitudinally. Generally each plant can be divided into 2 to 6 plants, or even as many as 10 plants. Note that when dividing, each seedling piece must carry a "seedling stem" with fibrous roots below. After division, soak the seeds in 1200 times dilution of 50% carbendazim for 1 to 2h for disinfection, take them out, spread them in the sun, then mix with fine soil or plant ash mixed with loess for seedling raising.

(3) Seed propagation method

The seed propagation method for daylily is fast and propagates in large numbers, and can provide the seedlings needed for large-scale cultivation. During the daylily growing period, do not harvest the flowers. Each capsule contains 10 to 50 plump, high-quality seeds. When the capsule changes from milky yellow to gray-black and splits open at the top, it can be harvested. Fully mature seeds are glossy black, with a 100-seed weight of about 2g. When sowing seeds to raise seedlings, a plot with fertile soil must be selected, made into small beds 1.0 to 1.2m wide, and sown from mid-to-late April to early June. Before sowing, first open furrows on the bed surface, 3 to 5cm deep, and sow at a row spacing of 15cm and a plant spacing of 1cm. After the seeds are sown, press lightly and cover with soil, with a soil-covering thickness of 2 to 3cm. Plastic film can be used to preserve soil moisture and raise temperature to promote seedling growth. After the seedlings emerge, the film must be broken to let in air to prevent scalding the seedlings. After the seedlings grow in the seedling bed for 1 year, they can be lifted and planted in the second year.

(4) Planting

Apart from the full seedling stage and the picking stage, daylily can be planted in other periods, but there are 2 most suitable planting seasons:

① Spring (March to April), that is, when the spring seedlings of daylily have just begun to grow. At this time, plants propagated by division have a high survival rate, and after 1 year of growth, they can enter the picking stage in the second year;

② Early autumn (September). Daylily planted in early autumn can take root and sprout in that autumn, grow a large number of leaves and new root groups, absorb a large amount of nutrients, and carry out leaf bud differentiation, laying a good foundation for producing new tillers the following year.

Dryland daylily generally adopts the wide-narrow row planting method, with wide rows 120 to 140cm, narrow rows 20 to 30cm, and hole spacing 9 to 15cm, planting 1 plant per hole, so as to facilitate mechanical cultivation and also help ventilation and light transmission and increase yield. When planting, open furrows on the selected plot according to the wide-narrow rows, with furrow depth 12cm and width 20cm. Place the daylily seedlings according to the specified plant spacing, and plant by hand-covering with soil, with a soil-covering depth of 10cm, so that "the top is not sealed and the roots are not visible below". After covering with soil is completed, press the covering soil firmly with your feet to facilitate full contact between the roots and the soil and promote rooting and sprouting.

2. Field management

(1) Management of planted seedlings

In the early stage after daylily seedlings are planted, if soil moisture is poor, water appropriately to increase the survival rate. After the planted seedlings survive, cultivate and weed in time to promote strong seedlings. Spring-planted seedlings should be cultivated and weeded 3 to 4 times throughout the year, and autumn-planted seedlings should be cultivated and weeded 2 to 3 times throughout the year.

(2) Management during the spring seedling stage

From seedling emergence to before bolting is called the spring seedling stage, lasting from March to May. After the Beginning of Spring, growth begins when the average daily temperature reaches above 5℃. As the temperature rises, leaves grow rapidly, and each tiller can grow 16 to 20 leaves, laying the foundation for reproductive growth. During the spring seedling stage, fertilizer should be applied early. After the spring seedlings turn green, open furrows on both sides of the seedling clump and apply urea at 500 to 600kg/hm2. At the same time, cultivate and weed once at the right time, to a depth of more than 10cm.

(3) Management during the bolting and budding stage

Late May to mid-June is the bolting stage. The newly emerged flower scape is pen-shaped, and flower buds appear as it grows. After the flower buds form, they gradually bloom. At this time, apply fertilizer once, opening furrows on both sides of the seedling clump and applying Stanley compound fertilizer at 400 to 500kg/hm2. At the same time, cultivate and weed once at the right time to loosen the soil and remove weeds.

(4) Management during the flowering stage

The flowering stage is the harvest stage, lasting from June to September. Depending on the variety, it can be harvested for 30 to 60d. In order to extend the picking period and increase yield, apply urea at 75kg/hm2 within 7 to 10d after picking begins. During the picking period, spray the leaves with 0.2% potassium dihydrogen phosphate aqueous solution about every 7d, which has a clear effect on strengthening buds and preventing bud drop.

(5) Management during the winter seedling stage

From the end of flowering to before Frost's Descent is the winter seedling growth period. The axillary buds on the lower part of the flower scape sprout and grow one after another, called winter seedlings. At this time, the organic matter produced by photosynthesis in the winter seedlings and other leaves is stored in the fleshy roots and shortened stem for the growth of spring seedlings the following year. Therefore, the growth of winter seedlings also affects the yield of the following year. At this time, cultivate and weed once to break soil compaction and improve soil water storage capacity; protect leaves and increase photosynthesis efficiency.

(6) Management during the dormant period

After Frost's Descent, all aboveground leaves die, and the plant enters the dormant period, from October to March of the following year. At this time, cut off dead leaves, remove weeds, and promptly plow or rotary till and harrow the soil in the wide rows, achieving depth, fineness, levelness and cleanliness, with a loose top and firm bottom and a level surface. In combination with land preparation, earth up and mound soil around the winter seedlings of daylily to enhance their cold resistance.

(7) Renewal and rejuvenation

When many rough and enlarged fleshy roots appear underground and the aboveground part tillers into a dense clump, it indicates that the daylily plant needs renewal and rejuvenation.

Specific method: after the harvest is completed, in combination with the autumn deep and medium cultivation, dig out 1/2 of the old plants together with the roots from one side of each clump as planting stock for continued propagation, prompting the whole plant to produce new tillers and sprout new roots, achieving the purpose of renewal and rejuvenation. After 3 to 4 years, use the same method to rejuvenate the other side.

3. Pest and disease control

(1) Rust disease

Rust disease can occur throughout the entire growth period of daylily, mainly harming leaves and flower stems. At initial infection, there are blister-like spots. As the disease develops, yellow-brown powder is released, and sometimes the blister spots merge into one patch, the epidermis curls up, and the area around the blister spots often loses green and turns pale yellow. The entire leaf turns yellow, and in severe cases the leaves of the whole plant die, the flower stems turn red-brown, and the flower buds shrivel or drop.

Control methods:

① Fertilize reasonably, drain promptly after rain, and prevent waterlogging in the field or excessive surface humidity;

② After harvest, pull up the scapes and cut the leaves and burn them in a centralized manner, and promptly turn the soil;

③ Loosen the soil and weed in early spring; fourth, in the early stage of disease, spray with 500 to 600 times dilution of 15% triadimefon wettable powder, or 600 to 800 times dilution of 20% triazolone wettable powder for control, spraying once every 7 to 10d, for 2 to 3 consecutive sprays.

(2) Leaf blight

Leaf blight mainly harms leaves. At initial infection, there are round pale small spots at the leaf tips. As the disease develops, the leaves turn yellow-brown along the edges and dry up. If humidity is high, black mold-like matter is produced.

Control method: spray with 800 times dilution of 75% chlorothalonil wettable powder, spraying once every 7 to 10d, for a total of 2 to 3 sprays.

(3) Red spider mite

Red spider mites gather as nymphs and adults on the back of leaves to cause damage. Gray-white small spots appear at the damaged areas, and in severe cases the entire leaf turns gray-white and eventually dies.

Control method: spray with 1500 times dilution of 15% saomanting wettable powder, or 2000 times dilution of 73% propargite.

(4) Aphids

Aphids mainly occur in May, first harming leaves, then gradually developing to flowers and flower buds. After being damaged, the flower buds become thin and small and easily drop.

Control method: spray with 1000 to 1500 times dilution of 10% imidacloprid wettable powder, or 1500 to 2000 times dilution of 10% acetamiprid wettable powder.

4. Picking

Harvest when the flower buds are yellow-green, plump, with obvious longitudinal grooves on the petals, and ready to bloom. Harvesting too early means the flower buds have not fully expanded and the yield is low; harvesting too late means the flower buds split open or bloom, affecting yield and quality. The best harvest time is 2h before the flowers split open, generally from 7:00 to 14:00, picking the early-ripening ones first and the later-ripening ones later.

5. Processing

(1) Steaming

Steaming to fix the color is a key process that determines the quality of dried daylily. The picked flower buds must be steamed promptly. Before steaming, remove flower buds that have already opened, and steam them in a multi-layer steamer. The layer should be loose, with a thickness of 6 to 10cm, and a small hole should be left in the middle to allow steam to rise. The steaming temperature is 75 to 80℃, the steaming time is 8 minutes, and at 5 maturity, when the color changes from yellow to green, the flower stalk begins to soften, and rubbing the flower buds with the hand gives a slight rustling sound, it is ready.

(2) Sun-drying

Spread the steamed flower buds thinly on a drying curtain, and place the drying curtain on a flower-drying rack so that it is elevated, to help moisture dissipate in all directions. Generally, 2 to 3d of drying is enough to dry them. During drying, turn them frequently and prevent rain from soaking them. Well-dried daylily is suitable when it does not crumble when gripped tightly in the hand, can scatter when the hand is released, and does not stick to each other.

(3) Storage

After daylily is dried, it has a very strong moisture-absorbing ability, so it should be packed and sealed in chemical fiber bags or plastic bags and stored in a dry, cool place.