What are the key technical points for planting daylily in autumn and winter?

Daylily (scientific name: Hemerocallis citrina Baroni), also known as golden needle vegetable and lemon daylily, belongs to the order Liliales, family Liliaceae, a perennial herbaceous plant, with roots nearly fleshy, often spindle-shaped and swollen in the middle and lower parts. The flower scapes vary in length, the pedicels are relatively short, the flowers are numerous, and the perianth is pale yellow, orange-red, or black-purple; the capsule is obtusely triangular-elliptic, and the flowering and fruiting period is from May to September. [1] Its nature and flavor are sweet and cool, and it has effects such as stopping bleeding, reducing inflammation, clearing heat, and draining dampness. It is rich in pollen, sugar, protein, vitamin C, calcium, fat, carotene, amino acids, and other nutrients necessary for the human body. It is mainly distributed in China.

Growth habits of daylily

Daylily is tolerant of poor soil and drought, has low requirements for soil, and can be cultivated at field edges or on hillsides. It has a wide range of adaptability to light and can be intercropped with relatively tall crops. The aboveground part of daylily is not cold-tolerant, while the underground part can tolerate low temperatures of -10°C. It avoids excessively wet or waterlogged soil. When the average temperature over ten days is above 5°C, the seedlings begin to emerge, and the suitable temperature for leaf growth is 15°C to 20°C; the flowering period requires a higher temperature, with 20°C to 25°C being more suitable.

Key points for how to plant daylily in autumn and winter

1. Soil selection. Daylily has strong adaptability to soil and can grow in soils of various properties. It is not very strict about soil pH, and generally slightly acidic to slightly alkaline soil can be used for cultivation, with pH 6.5 to 7.5 being best. The daylily root system is well developed and penetrates relatively deeply, so it is best to choose loam, clay loam, and sandy loam with deep soil layers and fertile texture for cultivation. 2. Deep plowing and land preparation. The daylily root system is well developed, and land preparation requires deep plowing of more than 33 cm to ensure normal root growth. Deep plowing can increase the water storage capacity in the soil and reduce the harm of drought. During land preparation, plan the walkways and build irrigation facilities well according to the size of the plot. For flatland cultivation in beds, generally about every 15 rows form one bed. The ditch between beds is about 25 cm wide and 15 to 18 cm deep. For larger, level, and broad land, open a main ditch 25 to 30 cm wide and more than 30 cm deep around the perimeter and every 4 to 5 beds to facilitate drainage. 3. Apply sufficient base fertilizer. The base fertilizer is mainly organic fertilizer and can be applied in furrows or holes. Before planting, while preparing the land, dig planting furrows more than 30 cm deep or planting holes 15 to 20 cm deep and 25 to 30 cm wide according to the row spacing. For every 667 sq m, use 3000 to 4000 kg of decomposed barnyard manure and 50 to 75 kg of superphosphate, apply them in layers, and after application cover with 5 to 7 cm of fine soil so that the seedling roots do not directly contact the fertilizer, to prevent the occurrence of “root burn”. Then fill in surface mature soil, level it, and planting can begin. For every 667 sq m, also use 250 kg of human manure and urine diluted with water to pour over the root crowns. 4. Seedling treatment. Trimming the seedlings before planting can reduce the consumption of water and nutrients by the plant, reduce sources of pathogens, and enable the remaining leaves, shortened stems, and roots to have stronger vitality. After planting, they can quickly produce new roots and sprout new buds, improving the survival rate. When trimming, remove the black base below the shortened stem and the spindle roots on the fleshy roots, cut the root system short to 5 to 7 cm, and remove decayed roots. Then cut the seedling leaves short to 6 to 7 cm and remove remnant leaves. Before planting, soak the seedlings in a 1000-fold solution of 50% carbendazim wettable powder or 50% thiophanate-methyl wettable powder for 10 minutes, and after drying until the surface no longer appears wet, proceed with planting. 5. Reasonable close planting. Reasonable close planting is an important measure for increasing daylily yield per unit area, and it must be determined according to the tillering habits of daylily and the growth and development characteristics of the flower scapes and flower buds. Generally, for flatland, fertile land, and varieties with weak tillering ability, planting 1800 to 2000 clumps per 667 sq m is appropriate. The planting method adopts wide and narrow row clump planting, with wide rows 100 cm, narrow rows 65 cm, and hole spacing 40 to 50 cm. 6. Proper deep planting. The daylily root mass develops from the shortened stem and produces new roots once each year from bottom to top. If planted too shallow, it is easily threatened by autumn and winter drought, affecting survival and emergence, and if heavy rain washes the soil within one or two years after planting, it will cause the root system to be exposed, affecting the root system's absorption and utilization of water and nutrients, and hindering plant growth and development. Shallow planting causes rapid tillering, dense clumping, underdeveloped roots, weak plant growth, thin and weak flower scapes, few and light flower buds, and low yield. However, if planted too deep, tillering is too slow, and entry into the high-yield period is delayed by 1 to 2 years. Therefore, daylily must be planted properly deeply, generally about 13 cm being appropriate. When planting, first open the planting furrows or planting holes well, place the seedlings in, cover the root crowns with a little soil, then apply fertilizer, cover with local soil, and make the seedlings emerge 3 cm above the soil surface. The height of the covered root crown should be level with the bed surface.