Off-season Cultivation Methods and Technical Key Points for Cilantro
Cilantro, also known as coriander, salt coriander, hu coriander, fragrant coriander, yan coriander, mantianxing, etc., is an annual herbaceous plant of the genus Coriandrum in the family Apiaceae. It was initially called hu coriander, with the English name Coriander Herb, and is native to Central Asia and Southern Europe, or the Near East and the Mediterranean region. Records of cultivation techniques and pickling methods already exist in the "Qimin Yaoshu." Its tender stems and fresh leaves have a special fragrance and are often used as a garnish and flavor-enhancing ingredient in dishes.
Morphological characteristics of cilantro
Annual or biennial, a strongly scented herb, 20-100 cm tall. Root fusiform, slender, with numerous fine branch roots. Stem cylindrical, upright, much branched, striated, usually smooth. Basal leaves petiolate, petiole 2-8 cm long; leaf blade 1 or 2 times pinnately parted, segments broadly ovate or fan-shaped and half-parted, 1-2 cm long, 1-1.5 cm wide, margins obtusely serrate, incised, or deeply parted; upper stem leaves 3 to many times pinnately parted, ultimate segments narrowly linear, 5-10 mm long, 0.5-1 mm wide, apex obtuse, entire. Umbels terminal or opposite the leaves, peduncle 2-8 cm long; rays 3-7, 1-2.5 cm long; involucel bracts 2-5, linear, entire;
Umbellules with 3-9 fertile flowers, flowers white or tinged with pale purple; calyx teeth usually unequal in size, the small ones ovate-triangular, the large ones oblong-ovate; petals obovate, 1-1.2 mm long, about 1 mm wide, apex with an incurved small ligule, radiant petals 2-3.5 mm long, 1-2 mm wide, usually entire, with 3-5 veins; filaments 1-2 mm long, anthers ovate, about 0.7 mm long; styles upright when young, reflexed outward when fruit is ripe. Fruit globose, dorsal main ribs and adjacent secondary ribs conspicuous. Endosperm concave on the ventral side. Oil ducts inconspicuous, or 1 located below the secondary ribs. Flowering and fruiting period April to November.
How is cilantro cultivated off-season?
1. Variety selection
For off-season cultivation of cilantro in summer and autumn, it is advisable to choose cilantro varieties that are tolerant of damp heat, disease-resistant, strongly stress-resistant, and of the large-plant, large-leaf type.
2. Seed treatment
Cilantro seeds germinate with difficulty under high-temperature conditions. Before sowing, soak the seeds in a 300-fold dilution of 1% carbendazim wettable powder for half an hour, then remove and rinse them clean, then soak them in clean cold water for about 20 hours, and then germinate them at 20-25 degrees C before sowing.
3. Land preparation and fertilization
Choose a plot with convenient drainage and irrigation and loose, fertile soil. After the previous crop is harvested, plow deeply 20-25 cm in time and sun it for 15 days. To facilitate the use of shade netting, make deep-furrow high beds with a bed width of 120 cm, a height of 20 cm, and a furrow width of 30 cm. The growing period of cilantro is relatively short. In combination with land preparation, apply 3500 kg of decomposed human manure and urine, 150 kg of cake fertilizer, and 50 kg of calcium magnesium phosphate fertilizer per mu as base fertilizer. The surface soil of the bed should be finely broken up and leveled to facilitate uniform emergence.
4. Timely sowing
For off-season cultivation of cilantro in summer and autumn, sowing is generally carried out from mid-May to early July, with a seeding rate of 1 kg per mu, which can both achieve relatively high yield and obtain a relatively high selling price. When soil moisture is suitable, broadcast evenly and then cover with 1-2 cm. Cover with straw mats to preserve moisture and maintain soil moisture and promote seedlings; remove them after 5-7 days, and pay attention to maintaining soil moisture during this period.
5. Field management
As summer and autumn temperatures gradually rise, this will affect the growth of cilantro. Therefore, after removing the straw mats, promptly set up frames and cover with shade netting. The shade netting should be covered during the day and removed at night to strengthen ventilation and prevent seedlings from growing spindly and triggering diseases. Because cilantro has a short growing period, it is advisable to weed early, thin seedlings early, and apply quick-acting nitrogen fertilizer early. Generally, thinning should be carried out about 7 days after full emergence, and final thinning at the 2 true-leaf stage, with a seedling spacing of 2-3 cm. Usually water once about every 8 days. When seedlings are 3 cm tall, start topdressing, applying 10-15 kg of urea and 250 g of boron fertilizer per mu. Afterward, in combination with irrigation, apply ammonium bicarbonate or urea in 2-4 split applications, and when applying foliar fertilizer later, add an appropriate amount of potassium dihydrogen phosphate to promote leaf growth.
6. Pest and disease control
Pest and disease control for pollution-free cilantro should follow the principle of giving priority to prevention and supplementing with treatment, combining multiple control methods to keep pests and diseases within the smallest possible range.
1. Agricultural control: base it on varieties with strong disease resistance, implement crop rotation, and avoid continuous cropping. Promptly remove diseased plants and diseased leaves in the field to reduce opportunities for pathogen infection. Strengthen fertilizer and water management to improve plant disease resistance.
2. Physical and biological control: apply physical control techniques such as frequency-vibration insect-killing lamps, sex attractants, and Bt powder.
3. Chemical control: the main diseases include damping-off at the seedling stage, and viral disease, anthracnose, and leaf blight at the adult plant stage. Five days after emergence, spray once with a 800-fold dilution of the pollution-free fungicide 3% polyoxin, and afterward spray once every 7 days with a 600-fold dilution of polyoxin, for a total of 2-3 sprays, which can prevent damping-off, anthracnose, and leaf blight. To control viral disease, insect-proof nets can be used to prevent the aphids that transmit it from flying in; shading can be used to avoid a high-temperature and drought environment and reduce the occurrence of aphids; and 20 g of 20% imidacloprid wettable powder can be added to 50 kg of water and sprayed on the foliage to thoroughly control aphids and prevent the occurrence of viral disease. For leafminers, spray with a 1500-fold dilution of 1% abamectin.
7. Harvest
About 40 days after sowing, it can be harvested. About 15 days before harvest, spray 20-25 ppm gibberellin, which can make the leaves elongate, increase branching, and result in high yield.