When is the best time to plant peanuts? A detailed explanation of planting time
The peanut is a nut with abundant yield and widespread consumption in our country, also known as groundnut, longevity fruit, mud bean, foreign bean, earth bean, etc. It is an annual herbaceous plant of the genus Arachis in the family Fabaceae, order Rosales. Its producing areas are mainly distributed in Brazil, China, Egypt and other places. It is suitable for planting in sandy soil areas with a warm climate and moderate rainfall, and its growing season is relatively long. Now let us take a look at the planting time of peanuts!
Peanut planting time
In the southern two-crop spring and autumn peanut region, the suitable sowing period is from February to mid-March; in the Yangtze River basin spring-summer peanut alternating region, the suitable sowing period is from March to late April; in the northern large peanut region and peanut-producing areas, the suitable sowing period is mostly from late April to early May. When sowing peanuts, if the soil temperature at a depth of 10 cm remains stable above 15 degrees for 5 consecutive days, sowing can begin. Remember, never sow when the temperature is below 11 degrees, to prevent seed rot and dead seedlings. Even if the peanuts can emerge, the peanut seedlings will not be robust, affecting yield. In summer peanut planting areas, intercropping can be chosen, sowing earlier to increase yield.
Peanut sowing methods
1. Sowing method: Peanut sowing methods are divided by cultivation method into open-field sowing and film-mulched sowing, and by operation method into manual dibbling and mechanical sowing.
2. Sowing density: Peanut planting density is determined by plant height, fruiting range and leaf area size. The suitable planting density depends on climatic characteristics, soil fertility, selected varieties and cultivation conditions.
3. Sowing depth: Generally, peanut sowing should be about 5 cm deep. Master the principles of “do not sow deep when dry, do not sow shallow when wet” and sow shallow in clay soil, deep in sandy soil or plots with high sand content. For open-field cultivation, the deepest must not exceed 7 cm, and the shallowest must not be less than 3 cm.
4. Pressing after sowing: Pressing after sowing is a successful experience for drought-resistant peanut sowing to ensure a full stand. After pressing, it not only reduces soil moisture evaporation, but also brings the seeds into close contact with the soil, promotes the rise of lower soil moisture, prevents the seeds from drying out, and facilitates seed germination and emergence.
Peanut planting techniques
1. Land leveling: The peanut is an economic crop that flowers above ground and, after forming pegs, drills into the ground to bear fruit. It is suitable for planting in loose sandy soil and oil-sand soil. The plot for planting peanuts should be deep-plowed, and together with plowing, apply 30-40 tons of high-quality farmyard manure per hectare, then press 1-2 times after plowing. Where conditions permit, irrigation can be done first, then farmyard manure and chemical fertilizer mixed and applied into the furrows, ridged and pressed, ready for timely sowing.
2. Cultivated varieties: For high peanut yield, good seed is the foundation. Peanut varieties suitable for planting mainly include the Fuhua series and the Jifu series (commonly known as Sililong), with a growth period of about 110-120 days. Select pods that are large, plump, uniformly shaped and unbroken as seed. Before shelling, sun-dry for 1-3 days; after shelling, further select seeds, choosing seeds with pure color and uniform shape as seed.
3. Scientific fertilization: Peanuts are relatively tolerant of poor soil, so fertilization should be mainly base fertilizer, applying 30 tons of farmyard manure per hectare. Chemical fertilizer should be mainly phosphate fertilizer, applying 300-400 jin of diammonium phosphate per hectare. For planting peanuts in poor soil, apply an additional 200-300 jin of urea per hectare.
4. Replanting and thinning: For peanuts, from late May to early June, investigation of seedling conditions should be carried out as early as possible. For fields with obvious gaps in seedlings, replant as early as possible. Replanting can use the method of pre-germinating and watering at planting, and complete thinning and final singling of seedlings.
5. Clearing around seedlings to strengthen them: After peanut seedlings emerge completely, use a small hoe to dig a ring of soil around the seedlings at a distance of 2 cm, then gently scrape the two cotyledons out of the ground with the hand. Clearing around seedlings to strengthen them is generally done three days after the first hoeing and ridging.
6. Timely hoeing and ridging: After peanut seedlings emerge, begin hoeing. Three days after hoeing, do the first ridging; after 15-20 days, do the second hoeing and ridging. Be careful not to press the seedlings when earthing up. At the end of the peak flowering period, finish the third hoeing and ridging. When closing the rows, ridge in four directions to facilitate the pegs penetrating into the soil, and at the same time be careful to pull out large weeds.
7. Reasonable topdressing: During the pod-filling and full-fruit stage of peanuts, according to growth conditions, targeted foliar spraying can be used to topdress fertilizers such as potassium dihydrogen phosphate (suitable concentration 0.3%) and plant growth regulators such as Lufeng 95, to promote seed formation.
8. Timely harvest: When peanut leaves turn yellow and some stems and leaves wither, they can be harvested, generally in mid-September. After harvest, dry them to reduce moisture, promote after-ripening, and improve seed maturity. Peanuts kept for seed must be harvested and dried before frost.
Alright, that is all for the peanut planting time and planting techniques introduced by the editor. Now let us take another look at peanut pest and disease control techniques!
Stem rot
[Symptoms] At the seedling stage, the cotyledons are dark brown and dry-rotten, then spread along the petiole to the stem base, forming yellow-brown water-soaked lesions, and finally becoming dark brown rot. In later stages, lesions first appear at the stem base or main and lateral branches, water-soaked, yellow-brown, then dark brown, and the aboveground part wilts and dies. Peanut stem rot occurs severely, with about 80% of the area affected. The general incidence rate is 60-70%, and in severe cases diseased patches reach as high as 80-90%. Some severely diseased plants have died entirely.
[Control] Before sowing, dress seeds with 50% carbendazim wettable powder (dosage 0.3-0.5% of seed weight), or use 0.5 kg of 50% carbendazim wettable powder plus 50-60 kg of water to cold-soak 100 kg of seeds for 24 hours before sowing, with remarkable control effect. In the early stage of disease, choose 50% carbendazim wettable powder or 65% zineb wettable powder 500-600 times solution, or 70% thiophanate-methyl wettable powder 800 times solution for spraying, once every 7 days, spraying 2-3 times consecutively.
Root rot
[Symptoms] This disease can occur throughout the entire growth period of peanuts. Infected plants are stunted, and leaves turn yellow from bottom to top successively, dry up and fall off. The outer skin of the main root turns black and rots, until the whole plant dies. This disease mainly spreads through rainwater and in the field. Water accumulation in the field at the seedling stage, low soil temperature, or sowing too early or too deep can easily trigger this disease.
[Control] ① Level the land and improve the soil, apply more decomposed organic fertilizer, prevent waterlogging and drain water, and strengthen field management. ② Dress seeds with 50% carbendazim wettable powder at 0.3% of seed weight. In the early stage of disease, spray the whole field with 50% carbendazim 1000 times solution.
Leaf spot
[Symptoms] Brown spot lesions are round, dark brown, relatively large, with a yellow halo at the outer edge, and later gray mold-like matter. Black spot lesions are round, dark brown, without a yellow halo around the lesion, and smaller than brown spot lesions.
[Control] In the early stage of disease, when the diseased leaf rate in the field reaches 10-15%, the first spraying should begin. The pesticide can be 50% carbendazim wettable powder 1500 times solution, or 50% thiophanate-methyl wettable powder 2000 times solution, or 80% zineb wettable powder 400 times solution, or 80% mancozeb 400 times solution, 75% chlorothalonil wettable powder 600-800 times solution, or Kangku Ning 700 times solution, or lime sulfur mixture of 0.3-0.5 degrees Baume, etc. After that, spray once every 10-15 days, spraying 2-3 times consecutively, with 50-75 kg of spray liquid per mu each time.
Peanut rust
[Symptoms] The bottom leaves are affected first, and the leaves produce yellow blister spots, small, surrounded by a very narrow yellow halo. After the epidermis cracks, rust-colored powder is released. In severe cases, the leaves turn yellow, dry up and fall off.
[Control] When the diseased plant rate in the field reaches 10-20%, choose 50% colloidal sulfur 150 times solution, or Disodium rust 600-800 times solution, or 75% chlorothalonil 800 times solution, or 1:2:200 (copper sulfate:quicklime:water) Bordeaux mixture, or 25% triadimefon wettable powder 3000-5000 times, spraying once every 10 days or so, 3-4 times consecutively. Disodium rust should not be used continuously, and should be alternated with other pesticides. Each time spray 60-75 kg of spray liquid per mu.
Peanut net blotch
[Symptoms] Natural onset in the field generally starts from the bottom leaves of the plant. At first, small brown needle-head-sized spots appear on the front of the leaves, gradually becoming brown starburst-shaped spots, then expanding into a net-like pattern with gray-green edges. As the lesions gradually expand, they finally form round, oval or irregular brown to chestnut-brown large spots. The lesion edge is light greenish-brown with an indistinct boundary, causing premature leaf fall. The back of the leaf has no symptoms initially, and later shows light brown lesions with unclear edges.
[Control] In addition to the pathogen remaining in diseased and residual peanut leaves falling into the field, crop rotation, and selecting disease-resistant varieties, when the diseased plant rate in the field reaches above 5%, choose Kangku Ning 700 times solution, 80% mancozeb 400 times solution, “Nongkang 120“ (0.5 kg per mu) 200 times solution. Use 75-100 kg of spray liquid per mu each time, spray once every 10-15 days, 2-4 times consecutively.
Peanut bacterial wilt
[Symptoms] Peanuts are generally most susceptible to this disease at the early flowering stage. At the beginning, in diseased plants, the first and second leaves at the top of the main stem first lose water and wilt, delaying leaf opening in the morning and closing leaves early in the afternoon. After 1-2 days, the whole plant or one side of the leaves wilts rapidly from top to bottom, with a dull color, appearing blue-green. In later stages, diseased leaves turn brown and scorched. Diseased plants are easy to pull up. The tip of the main root, fruit stalk and pod are dark brown and wet-rotten, and the root nodules are dark green. The vascular bundles in the longitudinally cut diseased stem are dark brown. On the cross-section, when kept moist and slightly squeezed, white mucus can be seen overflowing.
[Control] Before sowing, soak seeds in 1000 times 32% Kejun solution for 8-12 hours for disinfection and sterilization. In the early stage of disease, spray 2500-3000 times agricultural streptomycin or Xinzhi streptomycin, or 1500-2000 times 32% Kejun solution, once every 7-10 days, spraying 3-4 times consecutively for control. In addition, spraying Baode biological foliar fertilizer at the early flowering stage can promote beneficial microbial activity in the root system and also play a certain role in inhibiting the development of the pathogen.
Black mold
[Symptoms] Black mold mainly occurs in the early growth stage of peanuts. The pathogen first infects the cotyledons, making them black and rotten, then infects the root and stem parts of the seedlings. When moist, many mold-like substances grow on the diseased part, covering the stem base, and the stems and leaves lose water, wilt and die.
[Control] Level the land and improve the soil, apply more decomposed organic fertilizer, prevent waterlogging and drain water, and strengthen field management. Dress seeds with 50% carbendazim wettable powder at 0.3% of seed weight.
Southern blight
[Symptoms] After peanut roots, pods and stem bases are infected, they first appear brown and soft-rotten. At the root-stem area of the aboveground part, white silky mycelium appears (hence called southern blight), along with rapeseed-like sclerotia. Stems and leaves turn yellow and gradually die, and peanut pods rot. The pathogen begins to germinate under high temperature and high humidity conditions and infects peanuts. It occurs more severely in sandy soil, continuous cropping, and overly dense unventilated conditions, and on cloudy and rainy days.
[Control] At the peanut sowing stage, apply 1 kg of quintozene per mu mixed with 20 kg of fine moist soil, place it in the sowing furrow and cover the seed. At the same time, pay attention to using pesticides such as Shennongdan and phorate to prevent underground pests. In the early pod-setting stage of peanuts, spray 20% triadimefon emulsifiable concentrate 1000 times solution or iprodione 1000 times solution for control. During the disease period, triadimefon, root rot spirit, thiophanate and other pesticides can also be used to drench the roots, with very obvious control effect.
Peanut pest control
1. Reasonable crop rotation: Good preceding crops for peanuts are gramineous crops such as corn and millet, avoiding continuous cropping.
2. Deep plowing in autumn: Deep plowing in autumn can turn pests up to the ground surface, causing them to die from exposure or be pecked by birds, reducing pest sources.
3. Seed coating: Coat seeds with seed coating agent before sowing. This method can also effectively prevent rodent damage.
4. Soil treatment: When preparing the land before sowing, evenly broadcast 22.5-30 kg of 3% granular carbofuran per hectare or 22.5-30 kg of 3% phorate granules on the field surface, then shallow-plow into the soil, or scatter carbofuran and phorate granules in the sowing furrow before sowing, or mix insecticides into organic fertilizer for use as base fertilizer.
6. Control larvae: In late June and late July, during the peak hatching stage and young larval stage of scarab beetles, apply 35-45 kg of phoxim granules per hectare plus 250-300 kg of fine soil and scatter it around the peanut root zone, then shallow hoe into the soil. Alternatively, drench the roots with 50% phoxim or 90% trichlorfon 1000 times solution.