Space Lotus 36 Cultivation Techniques: Combining Base Fertilizer with Top Dressing

SummarySoil: Suitable for planting in fertile, loose fields with convenient drainage and irrigation. Apply decomposed pig and cattle manure and scatter quicklime. One day before transplanting, plow and harrow the soil level. Transplanting: Carry out transplanting in late March or early April. Select healthy, thick and strong seed lotus roots and disinfect them with chemicals, then divide the plants for planting. Field management: Do a good job of checking and replanting seedlings, irrigation and weeding. Fertilization: Follow the method of combining organic and inorganic fertilizers, and combining base fertilizer with top dressing.

I. Soil Requirements 

1. Choosing a lotus field: The lotus field is suitable for planting in fields with ample sunlight, convenient drainage and irrigation, fertile and loose soil, high soil organic matter content, and no lotus root rot disease. It must not be planted in cold-water fields, mountain valley fields, rust-water fields, or leaky fields.

2. Plowing and fertilizing: For winter fallow fields, around the Spring Festival, combined with two plowings and two harrowings, apply 2000kg of human manure and urine or 2500-3000kg of decomposed pig and cattle pen manure per mu, then scatter 50kg of quicklime. One day before or on the day of transplanting, plow and harrow the soil level so that the muddy field is flat and free of weeds.

II. Preparing for Transplanting

1. Transplanting time: Transplanting can be carried out when the average temperature stabilizes at around 12°C, that is, in late March or early April.

2. Selecting seed lotus roots: It is suitable to select seed lotus roots that are disease-free, fresh in color, thick and well-proportioned, with short and flat internodes, and with undamaged terminal buds and root bodies.

3. Disinfecting seed lotus roots: Before transplanting, the seed lotus roots need to be disinfected. They can be sprayed and sealed with a 1000-fold solution of 50% carbendazim for about 12 hours.

4. Planting density: An average of 250-300 terminal buds per mu. The number of seed lotus roots can be appropriately increased or decreased according to field fertility. Generally, for soil with higher fertility, fewer can be planted, while for fields with lower fertility, the planting density needs to be appropriately increased.

5. Planting method: Plant by dividing the plants, with a row spacing of 1.5×1.5—2.0 m. All terminal buds should face the center of the field, be buried into the field at a 45º angle, at a depth of 5-7cm, then covered with soil, leaving the lotus root section exposed above the soil surface.

III. Lotus Field Management

1. Checking and replanting seedlings: After Space Lotus grows floating leaves, check and replant seedlings. If there are seed lotus roots that have rotted and not sprouted, they need to be replanted in time.

2. Water management: Water management should follow the principle of shallow irrigation in the early stage, deep irrigation in the middle stage, and shallow irrigation in the late stage. At transplanting, irrigate with about 3cm of shallow water. From after planting to late April, irrigate with 3-6cm of deep water. When a cold wave arrives, irrigate with 12-15cm of deep water for insulation. From early May to late June, irrigate with 9.0-20cm of deep still water. From early July to late August, irrigate with 15-20cm of deep flowing water. From September to March of the following year, shallow water can be irrigated to let the lotus roots overwinter safely. Fields with suitable conditions can also be irrigated with deep water, which helps prevent and control Space Lotus root rot disease.

3. Intertillage and weeding: When the lotus runners produce standing leaves, intertillage and weeding should begin. During intertillage, first drain the water from the lotus field, remove weeds, and then carry out intertillage. Generally, this is done once about every half a month, and it can end when the lotus plants close the rows.

IV. Timely Fertilization

1. Fertilization principles

Fertilization can be carried out according to the soil nutrient status and growth conditions of Space Lotus. Soil testing can also be used to determine the appropriate fertilization amount and method. Follow the method of combining organic and inorganic fertilizers and combining base fertilizer with top dressing to achieve balanced fertilization.

Generally, it is appropriate to apply 18.2kg of phosphorus pentoxide, 26.3kg of potassium sulfate, and 36.4kg of pure nitrogen per mu. The ratio of nutrients N:P2O5:K2O is 10:5:7. Organic fertilizers such as urban waste, industrial waste, and human and livestock manure that has not been fermented and decomposed or has not met harmless standards must not be used. The selected chemical fertilizers need to meet the relevant national product quality standards.

2. Base fertilizer

In the early growth stage of Space Lotus, that is, from sprouting to growing floating leaves, the nutrients needed for the growth of Space Lotus are generally supplied by the Space Lotus itself. Therefore, long-acting organic fertilizer should be selected as the base fertilizer, and chemical fertilizers must not be applied. The base fertilizer can be applied before transplanting Space Lotus.

Per mu, 2000kg of human manure and urine, 2500-3000kg of decomposed pig and cattle pen manure, and 50kg of quicklime can be applied, and one-time application of 2kg of borax, 6-8kg of sulfuric acid, and 8-10kg of gypsum powder before transplanting Space Lotus is beneficial to the growth and development of Space Lotus.

3. Top dressing

Top dressing mainly uses quick-acting chemical fertilizers. According to soil fertility and the growth conditions of Space Lotus, fertilizers can be applied in stages during the standing leaf stage, early flowering stage, full flowering stage, and late picking stage.

Standing leaf fertilizer: In early May, when the plants grow 1-2 standing leaves, apply 1-1.5kg of 45% urea per mu, mix evenly with 1-1.5kg of potassium sulfate, and apply deeply 8-10cm from the curled leaves, at a depth of 6-8cm into the soil.

Early flowering fertilizer: In mid-to-late May, apply 5kg of urea and 10kg of nitrogen-phosphorus-potassium (N15—P15—K15) compound fertilizer per mu.

Flower and seedpod fertilizer: From early June to mid-July, around the solar terms of Grain in Ear, Summer Solstice, and Minor Heat, scatter 7-8kg of urea, 3-4kg of potassium sulfate, and 15kg of nitrogen-phosphorus-potassium (N15—P15—K15) compound fertilizer per mu each time.

Reserve fertilizer: From late July to early August, according to the plant growth, supplement 5kg of urea and 2-3kg of potassium sulfate per mu.

V. Leaf Removal

When preserving leaves and removing leaves at row closure, floating leaves, withered yellow leaves, and standing leaves that have not produced flowers can be removed. During the full flowering stage, remove standing leaves that have not produced flowers in 1-2 sessions, including standing leaves with dead flower buds. During picking, one lotus seedpod can be used, and the lotus leaves on the same node can be removed by hand, but those that are sparsely distributed may not be removed. In the late picking stage, a relative amount of green leaves needs to be maintained, which can promote full grains and the formation of new lotus roots, thereby improving the quality of lotus seed roots. In diseased fields, to avoid loss of lotus leaves and to prevent the spread of pathogens, leaf removal is generally not carried out.

VI. Pest and Disease Control

1. Principles of pest and disease control: Generally, prevention should be the main approach with integrated control. Agricultural control, physical control, biological control, and chemical control are suitable. Pesticides that are explicitly prohibited by the state, such as those with high toxicity, high residues, high teratogenicity, high carcinogenicity, and high bioaccumulation, and their mixed pesticides, must not be used. The principles for applying pesticides must strictly implement the provisions of GB4285 and GB/T8321.

2. Agricultural control: Before planting, purchase excellent disease-free varieties, implement rotational cropping, and strengthen intertillage and weeding later to reduce the occurrence of pests and diseases.

3. Physical control: Remove lotus leaves with high pest and disease density by hand and bury them in the lotus field soil. Pull out diseased plants by hand. Blacklight lamps can be used to trap and kill pests.

4. Biological control: Where conditions permit, natural enemies can be artificially bred, and biological pesticides can be used to control pests and diseases.

5. Chemical control

(1) When lotus armyworms occur from May to August, based on the gregariousness of larvae before the 3rd instar, manual capture can be used, or 15-20ml of decis per mu can be used with 60-80kg of water for control.

(2) When lotus aphids occur from May to July, 100-150g of 40% dimethoate 1000-1500-fold solution per mu can be used for control.

(3) When brown spot disease occurs in June-July, in fields where new plants are severely affected and the pathogen spreads from old leaves to new leaves, after pulling out the diseased plants, spray with 10% Score 2000-3000-fold solution for control.

(4) When lotus root rot disease occurs from mid-May to early July, after removing diseased plants in the early stage of the disease, use agents such as carbendazim and Lüxiang No. 1 for control.

(5) When Riptortus pedestris occurs from late July to early August, on sunny days at 4-5 pm, use 5% cypermethrin emulsifiable concentrate 2500-fold for control, with a dosage of 20-25g per mu, or 40% dimethoate 1000-fold solution for control, with a dosage of 75-100g per mu.

VII. Supplementary Pollination

1. Artificial pollination: It is suitable to use a clean brush before 9 am on sunny days to transfer pollen from the stigma of one lotus flower to the stigma of another lotus flower.

2. Releasing bees in the lotus field: One box of bees needs to be released for every 15-30 mu of lotus field. During this period, bees can collect pollen, thereby achieving the purpose of supplementary pollination.

VIII. Harvesting

1. It is suitable to harvest in the morning from late June to early October.

2. Generally, harvesting can be carried out when brown markings appear on the lotus seedpod, the lotus seeds and the seedpod cavities are slightly separated, and the seed coat of the lotus seeds is light brown.

3. The harvesting method needs to follow a fixed route and proceed in order, with rows of 400-500cm. During this period, do not walk all over the field, as it will affect the growth of the plants.