How to grow organic cauliflower? Planting techniques and cultivation management key points
Cauliflower is also known as cauliflower, huacai, yecaihua, etc. It is a variety of Brassica oleracea in the Brassicaceae family, native to the Mediterranean coast. The head is a white inflorescence, similar to the head of broccoli. Its product organ is a curd formed by the aggregation of pure white, shortened, plump and tender flower buds, flower branches and flower stems. Now let us take a look at the cultivation techniques for organic cauliflower!
Cultivation conditions for organic cauliflower
Cauliflower has a well-developed root system and strong regeneration ability, making it suitable for seedling raising and transplanting. It is susceptible to frost damage below 0°C, and it is difficult to form curds above 25°C. Leaf cluster growth and bolting and flowering require warmth, with an optimum temperature of 20-25°C. Curd formation must go through a low-temperature vernalization stage. It does not have strict requirements for light conditions, but has relatively strict requirements for moisture, being neither tolerant of waterlogging nor drought. It has strong adaptability to soil, but the best is sandy loam with high organic matter and deep soil layers. The suitable soil pH is 5.5-6.6. It has strong salt tolerance and can still grow normally in soil with a salt content of 0.3-0.5%.
Seedling raising techniques for organic cauliflower
1. Planting time: Cauliflower is mostly planted in spring and autumn each year. Most areas of North China are very suitable for people to plant organic cauliflower in autumn. When planting in autumn, sowing can be done in mid-July, planting in August, and harvesting at the end of October and early November. If choosing to plant in spring, sowing should be done at the end of January, planting at the end of March, and harvesting at the end of May and early June.
2. Seed treatment: Seed disinfection is a relatively economical and effective method to prevent cauliflower pests and diseases. Seeds should be treated with natural substance disinfection and hot water soaking techniques. For natural substance disinfection, soaking in 300 times potassium permanganate solution for 2 hours, 200 times wood vinegar solution for 3 hours, 100 times lime water for 1 hour, or 100 times copper sulfate solution for 1 hour can be used. After disinfection, soak seeds in hot water for 4 hours.
3. Seedbed disinfection: For organic cauliflower planting sites, physical or natural substances are generally used for soil disinfection. Soil disinfection substances can include 3-5 degrees Baume lime sulfur mixture, 100 times crystalline lime sulfur mixture, 30-50 kg quicklime, or 100 times potassium permanganate and 50 times wood vinegar solution sprayed on the seedbed for disinfection.
4. Cultivating strong seedlings: For autumn planting, rainproof and shaded sheds can be used for sowing and seedling raising. First prepare nutrient soil, water the seedling bed thoroughly, sow seeds by broadcasting or dibbling, cover with soil and plastic film. 20-25 grams of seeds are needed per mu, and the seedbed should be 4-5 sq m. After emergence, keep the bed surface moist, and pay attention to rain protection, weed control and thinning. When seedlings are weak, apply 30% biogas slurry 2-3 times. For spring planting, sunny beds can be used for seedling raising. From sowing to emergence, the seedbed should not be ventilated, with daytime temperature around 25°C and nighttime around 15°C. After emergence, ventilate appropriately, with daytime 20-25°C and nighttime 10-15°C. Harden the seedlings 1 week before transplanting.
Planting techniques for organic cauliflower
1. Land preparation and transplanting: Apply 5000 kg of fully decomposed organic fertilizer per mu, deep plow, rake level, and make beds. North China generally adopts flat bed planting, with bed width of 1.4-1.5 m, planting two rows of cauliflower per bed. For early-maturing varieties, plant spacing is 32-37 cm, for mid-maturing varieties 40-45 cm, and for late-maturing varieties 50-60 cm. Autumn planting density is small, while spring planting density is large.
2. Temperature management: Temperature should be managed according to seasonal climate changes, room temperature changes and cauliflower growth requirements for daily management such as heat preservation, cold protection and ventilation, mastering ventilation time and ventilation volume. During the period from transplanting to seedling recovery, keep warm and moist, with daytime temperature of 25°C and nighttime temperature of 15-20°C. From seedling recovery to the appearance of small curds is the leaf rosette growth period, with daytime temperature maintained at 20-25°C and nighttime temperature at around 15°C. The curd formation period requires cool climate conditions, with daytime temperature of 20-22°C and nighttime temperature of 10-15°C.
3. Water and fertilizer management: The principle of water and fertilizer management after cauliflower transplanting is to promote seedlings in the early stage, prompting plants to recover and form rosettes early; control water and fertilizer in the middle stage to promote root development; and promote curd development in the late stage to promote curd expansion. Generally, 3 key topdressings are applied. The first is 7-15 days after transplanting, the second is 30-40 days after transplanting when plants have 15-17 true leaves, and the third is when plants begin to bud. Each time, apply 1000 kg of high-quality organic fertilizer per mu or apply 25% biogas slurry. During curd formation, 30% biogas slurry can be used for foliar topdressing.
4. Moisture retention and branch pruning: The soil should be kept moist throughout the cauliflower growing period, especially during the curd enlargement period when water must not be lacking. However, cauliflower is also afraid of waterlogging, so drainage should be noted during the growing period. Cauliflower tends to produce side branches. Before harvesting the main curd, side branches should be removed, or when most main curds have grown to 12-16 cm, 3-4 side branches can be appropriately retained. Frequently clean dust from the plastic film to maintain cleanliness, improve light transmittance, and ensure normal growth of cauliflower.
5. Pest and disease control: Organic cauliflower may also suffer from some pests and diseases during growth. If not handled in time, it will reduce yield and affect the quality of organic cauliflower. Cabbage caterpillars and diamondback moths are common pests and diseases when planting organic cauliflower. After they occur, farmers should use Bacillus thuringiensis for control. If aphids appear on organic cauliflower, 1% soap solution can be used for control. In addition, when planting organic cauliflower, in order to reduce the occurrence of pests and diseases, net room cultivation can also be used.
6. Timely harvesting: The harvest period for organic curds is relatively strict. Harvesting must be timely and prompt. The harvest standard is that the curd has fully grown, the surface is round and neat, the edges have not yet spread open, the curd is relatively firm, and the color is deep green. For some varieties, after harvesting the main curd, side curds can also be harvested 2-4 times.
Planting techniques and cultivation management key points for green-stem loose-curd cauliflower
Loose-curd cauliflower is a type of cauliflower in the Brassicaceae family, Brassica genus. It is also known as loose cauliflower, green-stem loose-curd cauliflower, organic cauliflower, white-surface loose cauliflower, organic cauliflower, etc. It is named because its bud branches are longer, the flower layer is thinner, and the curd is not firm when fully expanded, appearing loose compared to ordinary cauliflower. Now let us take a look at the planting techniques for green-stem loose-curd cauliflower!
Cultivation characteristics
Loose-curd cauliflower has two prominent characteristics. First, it has good cooking tolerance and delicious taste. The vitamin C and soluble sugar content of loose-curd cauliflower are significantly higher than those of tight-curd cauliflower, making it very popular among consumers. Second, early and mid-maturing varieties have strong heat tolerance and wider adaptability. They can be cultivated in suburban areas with "delayed spring" and "advanced autumn" cultivation. In high mountain cultivation, they can be produced and marketed in summer and autumn, broadening the production and marketing time of cauliflower.
Field selection
1. Loose-curd cauliflower fields should be selected with loose and fertile soil, good soil stability, and strong water retention, water supply and oxygen supply capacity. The field should have complete water conservancy facilities and be able to drain and irrigate. For high mountain cultivation, low-lying land and sticky waterlogged land should not be used for planting cauliflower, otherwise plant growth will be poor and black root disease will easily occur. For early spring planting in plain areas, due to lower temperatures and less rainfall, it can be appropriately selected, but wide-furrow high beds should be made and plastic film should be used to prevent moisture and dampness.
2. For continuous cropping land, pest and disease control should be strengthened and trace fertilizers should be supplemented. Sloping dry land such as sweet potato fields has poor water retention capacity and is prone to drought. It can still be used in the first half of the year for high mountain cultivation, but in the second half of the year, if there are no watering conditions, it generally cannot be selected in normal years. For high mountain cultivation, altitude between 600-1200 m should be selected. For planting high mountain cauliflower in areas below 800 m altitude, the high-temperature season should be avoided, or more heat-tolerant varieties should be selected, such as "Qingnong 70 Days Green-Stem Loose-Curd Cauliflower", etc.
Cultivation season
1. Cultivation in low mountain areas below 350 m altitude: For spring planting, sow from late December to early January, raise seedlings with heat preservation in large sheds with small arch sheds, and transplant from late February to early March with plastic film plus small arch sheds. If sowing from late February to early March, raise seedlings with heat preservation in large sheds or small arch sheds. Open-field transplanting can be done from late March to early April. Harvesting and marketing can be done from April or mid-May to early June. For autumn planting, sow from mid-June to July, raise seedlings under shading, transplant from early July to August, and harvest and market from late August to early November.
2. Cultivation in high mountain areas at 800-1200 m altitude: Sow from mid-February to mid-March, seedling age about 30 days, transplant from mid-March to mid-April, and harvest from mid-May to June. Qingnong 65 Days: sow from late March to July, seedling age 20-35 days, transplant from late April to mid-August, and harvest from late May to early November. High mountain seedling raising all uses protected facilities (mostly small arch sheds), which can provide heat preservation and cold protection in spring, and rain protection and moisture retention in summer and autumn.
Topdressing fertilizers
1. During the seedling stage of loose-curd cauliflower, nitrogen fertilizer is mainly used, applying thin fertilizer frequently to promote rosette leaves. Before and after budding, phosphorus and potassium fertilizers are mainly used, with heavy application of bud fertilizer. Generally, fertilizer is applied diluted with water, which can prolong the bud expansion period and promote curd development and expansion. Under high temperature and drought conditions, soil moisture deficiency often hinders nutrient absorption by plants. Therefore, fertilization must be organically combined with water supply. Applying fertilizer diluted with water can improve fertilizer utilization and enhance quick effectiveness.
2. During the growth process of loose-curd cauliflower, medium and trace fertilizers such as boron, molybdenum, magnesium and sulfur should also be added to correct plant nutrient deficiencies. Among them, boron has a very significant impact on curd yield and quality, and must be applied as foliar topdressing 2-3 times, especially during the curd expansion period. In the mid-to-late topdressing process, ammonium bicarbonate or fertilizers containing ammonium bicarbonate should be refused to avoid hairy curds.
3. Loose-curd cauliflower fertilization is mainly based on decomposed manure and urine water, combined with quick-acting chemical fertilizers for balanced fertilization. The amount and frequency of fertilization should be determined according to plant growth and target yield. Generally, topdressing is applied once after transplanting and survival, at the early stage of rosette leaf formation, at the late stage of rosette leaf formation, and at budding, for a total of 3-4 times. At the same time, medium and trace element fertilizers such as magnesium, boron and molybdenum should be applied. Within 20 days before product harvest, no chemical fertilizer may be applied.
Earthing up and root covering
1. The root system of loose-curd cauliflower arises from the main stem and is layered. During growth, deep roots continuously age, and new roots continuously form on the stem near the ground. The overall distribution is relatively shallow, and fibrous roots are mainly distributed near the main stem. Observations show that in cool seasons the root distribution is deeper, while in warm and hot seasons it is very shallow, which may be related to the tropism of root growth to soil temperature. On the other hand, during agricultural operations, most base fertilizers and topdressings are applied relatively shallowly, which also promotes root growth toward the soil surface. Therefore, cauliflower production generally requires earthing up. Through earthing up, adventitious roots are promoted, the soil environment for root growth is stabilized, and plant vigor and lodging resistance are enhanced.
2. When high mountain cauliflower suffers from waterlogged roots due to excessive rain and high-temperature drought, the effect of earthing up is particularly obvious, enhancing stress resistance and significantly increasing yield. During the growth process, earthing up should generally be combined with weeding, loosening soil and fertilizing, 1-3 times. For cauliflower that is not earthed up, at least deep planting should be done. In production, cauliflower that is not earthed up and is planted shallowly has poor growth and yield. The method of earthing up is to place soil from the furrow and soil previously piled in the middle of the bed onto the planting holes and between plants, ultimately forming a turtle-back-shaped uniform bed surface. The practice of forming two small beds on one bed after earthing up is incorrect. In the field, this situation often occurs when earthing up is done on planting holes that are too shallow.
Water management
1. Loose-curd cauliflower has many and thin leaves, reaching 17-23 leaves in the mid-to-late growth period, 6-8 more than ordinary cauliflower varieties. The transpiration volume is large, and water loss and wilting often occur in the field, especially after continuous cloudy and rainy weather suddenly clears up, after heavy rain clears up, or under high temperature, drought and strong light conditions, the wilting phenomenon is particularly obvious. Therefore, the soil of loose-curd cauliflower planting fields should neither be too wet, causing waterlogged roots, nor too dry, causing water deficiency.
2. In general production, methods and measures such as clearing furrows for drainage, timely watering, earthing up and root covering, cutting grass for mulching, and plastic film mulching are used to timely adjust soil moisture conditions, strive for balanced water supply, and keep the soil moist and loose. During drought, irrigate with running water and water, and prohibit flood irrigation. After rain, drain in time and prohibit water accumulation in the field. Before transplanting and survival in summer, in case of drought, water once every evening. Under high temperature and strong light, shading is best.
Leaf binding to protect curds
1. Loose-curd cauliflower curds turn yellow when exposed to sunlight whether in spring or midsummer, and the color change is deeper under strong light in summer and autumn. This change not only affects the commercial appearance but also affects the fresh and tender quality of the curd. Therefore, curd care is an important part of high mountain loose-curd cauliflower production. Unlike the curd care of ordinary cauliflower, loose-curd cauliflower mostly uses leaf binding to protect curds rather than leaf folding to cover curds, especially in the production process mainly aimed at cultivating large curds with sparse planting, because its curds are fluffy and large, the inner leaves have poor overlapping and wrapping ability, and it has the characteristic that curd development and leaf emergence proceed simultaneously. Leaf folding to cover curds is often displaced by curd expansion and inner leaf growth, resulting in poor shading effect.
2. The specific method of leaf binding to protect curds in loose-curd cauliflower is: when the curd grows to the size of a fist, pull 4-5 alternating large leaves near the curd toward each other and overlap them without breaking them, then use 1-2 small bamboo sticks, small grass stalks or small firewood sticks 2-3 mm thick and 7-10 cm long as fixing connectors, pierce and string the overlapping leaf tips and fix them at the main vein. The leaves fixed by stringing are tied up in a lantern shape, covering the entire curd, so that the curd is protected from direct sunlight during subsequent growth and still has enough space for development and expansion.
3. The stricter the shading and protection of loose-curd cauliflower, the better. Tight leaf binding to protect curds can completely prevent sunlight from reaching the curd, and even in midsummer conditions, the entire curd can remain white and tender. Compared with the usual leaf folding method to cover curds, leaf binding to protect curds is completed in one go, eliminating the trouble of repeated leaf folding and covering, saving labor and time, and having better results.
Pest and disease control
The main pests of loose-curd cauliflower include aphids, diamondback moths, leafminers, green caterpillars, cabbage caterpillars, cotton bollworms, beet armyworms, mole crickets, striped flea beetles, tobacco whiteflies, etc. Control should implement the plant protection policy of "prevention first, integrated control", giving priority to agricultural control, physical control and biological control, scientifically and coordinately using chemical control, strictly controlling the number of pesticide applications, observing safety intervals, and keeping pests and diseases below the allowable economic threshold, so that pesticide residues are controlled within the green food standards stipulated by the state, achieving the purpose of safety, high quality and harmlessness.
Key points for summer cultivation management of broccoli
Broccoli is an annual or biennial herbaceous plant, native to the eastern Mediterranean coastal areas. It is cultivated in small amounts in China, mainly for Western cuisine. Broccoli is rich in nutrients, containing protein, sugar, fat, vitamins and carotene. Its nutritional content ranks first among similar vegetables and it is known as the "crown of vegetables".
Broccoli is a type of vegetable and belongs to a variety of cabbage. Broccoli is a Brassicaceae plant, an annual or biennial herbaceous plant with broad leaves, a blunt base, wavy edges, smooth and hairless, and yellow-white flowers. Leaves grow from the roots, the main stem and branch stems grow from the leaves, and the stems are covered with small particles forming a flower-like shape. The flower is fleshy and blocky, and the whole resembles a large flower, white and beautiful. Broccoli has tender flesh and a sweet, delicious taste, and is easily digested and absorbed after eating.
Broccoli and cauliflower have well-developed root systems and strong regeneration ability, making them suitable for seedling raising and transplanting. They are susceptible to frost damage below 0°C, and it is difficult to form curds above 25°C. Leaf cluster growth and bolting and flowering require warmth, with an optimum temperature of 20-25°C. Curd formation must go through a low-temperature vernalization stage. Cauliflower does not have strict requirements for light conditions, but has relatively strict requirements for moisture, being neither tolerant of waterlogging nor drought. It has strong adaptability to soil, but the best is sandy loam with high organic matter and deep soil layers. The suitable soil pH is 5.5-6.6. It has strong salt tolerance and can still grow normally in soil with a salt content of 0.3%-0.5%.
Key points for summer cultivation management of broccoli
1. Select good varieties and sow at the right time
The suitable growth temperature for broccoli is between 16°C and 22°C. During the vegetative growth period, the suitable temperature range is wide. The flowering and budding period generally requires an average daily temperature below 25°C. If the bud development period encounters high temperatures (above 30°C), it will cause overly rapid bolting, low yield and poor curd quality. Therefore, selecting disease-resistant and heat-tolerant varieties and scientifically arranging sowing time are the keys to the success of summer sowing cultivation. Our county generally selects early-maturing and heat-tolerant excellent varieties imported from Japan such as Gaosheng, Balv and Zhulv, with 55-65 days from transplanting to harvest. Areas at 1000-1200 m altitude sow from late June to mid-July, and areas at 800-1000 m altitude sow from mid-July to early August. In order to facilitate harvesting and sales, it is best to sow in stages, 1 stage every 5-7 days. Harvest from late September to mid-November, striving to finish harvesting before coastal products are heavily marketed, which is conducive to increasing product prices and creating better economic benefits.
2. Cultivate strong seedlings and transplant at the right age
For summer cultivation of broccoli, which is in a high-temperature and rainy season, cultivating strong seedlings is key. Nutrient bag or nutrient soil ball seedling raising methods should be selected. Nutrient bags (or soil balls) are calculated at 3300-3500 per 667 sq m of field. The formula is 600-700 kg of fertile and loose paddy soil, 30-40 kg of rice husk ash, 80-100 kg of decomposed and fermented pig and cattle pen manure, 0.5-1.0 kg of imported compound fertilizer (preferably compound fertilizer containing potassium sulfate with N:P:K=21:6:13), 3 kg of calcium magnesium phosphate, 2 kg of lime powder, and 450 times 15% hymexazol solution (or quintozene) for soil disinfection. After mixing evenly, cover with plastic film, seal and pile for about 10 days. Before sowing, fill 8 cm × 10 cm seedling bags with nutrient soil (or print into nutrient soil balls), then sow 1 seed per soil bag (or soil ball), cover seeds with screened burned soil and miscellaneous fertilizer, and build a large shed, covering with a shading net with 65% shading rate. Strengthen fertilizer and water management during the seedling period. Transplant when the seedling age is 25-30 days (4 leaves and 1 heart - 5 leaves and 1 heart).
3. Select land, deep plow, and apply sufficient base fertilizer
According to the growth characteristics of broccoli and its requirements for environmental conditions, the planting site should be selected as paddy soil above 800 m altitude with deep soil layers, relatively high organic matter content, good drainage and irrigation conditions, strong water and fertilizer retention, and moderate sand and clay. Fields where the previous crop was cabbage must not be used. Most soils in southern mountainous areas are relatively acidic. About 1 month before transplanting, apply 100-1200 kg of lime powder per mu, combined with deep plowing and sunning, with a deep plowing depth of 30-35 cm. Base fertilizer should be applied throughout the layer 10-15 days before transplanting. Apply 1000-13000 kg of fermented pig and cattle pen manure and 120-200 kg of plant ash per mu; or use 500-600 kg of imported ternary compound fertilizer containing potassium sulfate and 200-300 kg of calcium magnesium phosphate. Broccoli has a relatively large demand for the trace element boron. Therefore, whether chemical fertilizer or organic fertilizer is used as base fertilizer, 2 kg of borax should be applied per mu to meet its growth and development needs.
4. High-bed cultivation and reasonable close planting
Broccoli is a crop that likes warm light but fears intense heat, and likes moisture but fears waterlogging. In order to improve light energy utilization, increase soil permeability and improve field microclimate, high-bed cultivation and reasonable close planting should be emphasized. In particular, the annual rainfall in southern mountainous areas reaches 1800-2000 mm, so deep-furrow high-bed cultivation is of special significance. Generally, the bed width including furrow is 1.1-1.2 m, bed height is 25-30 cm, and the surrounding drainage ditches and field waist ditches should be 50-60 cm deep, so that all ditches are connected and irrigation and drainage are easy. Gaosheng, Balv and Zhulv all belong to early-maturing broccoli varieties, which are conducive to close planting. Generally, plant spacing is 50-60 cm, row spacing is 35-40 cm, and 2800-3200 plants are planted per mu. When transplanting seedlings raised in nutrient bags, carefully tear off the nutrient bags and use shallow hole transplanting, with hole depth of 5-8 cm. Planting too deep will cause poor aeration at the stem base and easily induce damping-off disease.
5. Strengthen field management
1. Reasonable topdressing Broccoli generally requires 4 topdressings. After transplanting and survival, apply a seedling-promoting fertilizer, which can be applied with 10%-15% dilute human manure and urine. The 2nd and 3rd applications are carried out 15-18 days and 25-28 days after transplanting, with 5-6 kg of urea and 4 kg of potassium chloride per mu. The 4th application is carried out 37-40 days after transplanting. At this time, it has entered the rosette stage and is about to bud, which is a period requiring large amounts of water and fertilizer. The bud fertilizer should be applied heavily in time to promote rapid bud growth. Apply 20 kg of compound fertilizer containing potassium sulfate per mu, open holes 15-20 cm from the stem base for deep application (it is inconvenient to apply by watering after the rows have closed), cover with soil in time after application, and irrigate to moisten the soil so that the fertilizer dissolves and is absorbed. In order to promote robust plant growth and improve curd product rate, foliar fertilizers such as double-effect micro-fertilizer, Pen Shi Bao and Plant Power 2003 can be selected and sprayed once each at the seedling stage, vigorous growth stage and budding stage.
2. Scientific irrigation After broccoli transplanting, water to protect seedlings. If conditions permit, cover with shading materials to improve survival rate. After survival, control water appropriately to facilitate deep root growth. Water demand is large in the mid-to-late growth period, and water evaporates quickly in summer. In case of drought, water every evening, or irrigate with running water about once every 3 days to keep the soil moist. Cover the bed surface with rice straw or weeds to reduce water evaporation. At the same time, typhoons and rainstorms are frequent from July to September, so clear furrows and drain in time to meet the requirement that after rain stops, there is no water accumulation in the furrows.
3. Intertillage and earthing up Broccoli should be intertilled and earthed up 1-2 times before row closure. After row closure, no more intertillage should be carried out, but weeds should be pulled by hand. After typhoons and rainstorms, loosen the soil in time to prevent soil compaction, increase soil permeability, and promote root growth. Soil loosening should mainly be shallow hoeing, and care should be taken not to damage the roots.
6. Timely control of pests and diseases
1. Damping-off and seedling blight are the main diseases at the seedling stage. For damping-off, 500 times 58% metalaxyl mancozeb solution or 500 times 64% Sandofan solution can be used for spray control. For seedling blight, 1200 times 20% tolclofos-methyl EC, or 450 times 15% hymexazol aqueous solution, or 1000 times 70% dexon solution can be used, sprayed when diseased seedlings are first seen.
2. Bacterial soft rot, black rot and black spot These 3 diseases belong to bacterial diseases and are also major diseases in off-season cultivation, and should be controlled in time. Buds begin to differentiate as the susceptible stage. In the early stage of disease, use 1000 times 75% agricultural streptomycin solution, or 800 times 70% Kechade solution for spray control. When the disease is severe, use the above drugs alternately, spraying once every 5-7 days, continuously for 2-3 times, which can effectively control the disease.
3. Pest control mainly includes aphids, diamondback moths, cabbage caterpillars, beet armyworms, etc. Biological pesticide Bt 500-800 times solution can be used (when pest density is high, a small amount of pyrethroid pesticides can be added, but it cannot be mixed with fungicides), or 40% Lorsban 1000 times solution, 2.5% Kung Fu cypermethrin EC 2000 times solution, 21% Mieshabi 3000 times solution and other drugs for spray control.