To grow peanuts well, management at the middle and late stages is key

In peanut planting and production, if middle and late stage management cannot keep up, it will lead to lower peanut yields, which is a factor that seriously restricts the expansion of peanut planting area.

1. Timely topdressing and hilling. From the beginning of flowering to full flowering, a lack of fertilizer in peanuts easily reduces the number of flowers and affects peg penetration into the soil for pod setting, so reasonable nutrient supplementation should be carried out according to different situations.

1. For plots with insufficient base fertilizer or weak seedling vigor, apply 7.5-10 kg of urea, 10-15 kg of superphosphate, or 15-20 kg of nitrogen, phosphorus, and potassium ternary compound fertilizer per mu, which helps achieve uniform flowering, more pods, and ensures high yield.

2. In nitrogen-deficient plots, the young leaves of peanuts are pale yellow and small, and the veins lose green color; apply 5-7.5 kg of urea per mu. If phosphorus is deficient, the plants develop poorly, and the leaves are blue-green and curl upward; apply 7.5-10 kg of diammonium phosphate per mu, and spray 50 kg of 0.2% potassium dihydrogen phosphate solution on the leaf surface per mu. If potassium is deficient, the leaves are dark green with dry edges; apply 10-15 kg of potassium sulfate or 50-100 kg of plant ash per mu. If calcium is deficient, the plants grow slowly and the rate of empty shells is high; apply 40-50 kg of quicklime per mu to increase yield and improve quality.

3. Timely hilling. The key to hilling lies in timely operation. If too early, because the plants are still short, the fruiting branches are easily pushed up by soil and damaged, and weeds have not all sprouted, which can easily cause weed infestation. If too late, it prolongs the time for later pegs to enter the soil, which is unfavorable for the development of early pods and increases the number of young pods, shriveled pods, and rotten pods. The suitable time for hilling is when a single peanut plant is at full flowering, a few pegs have entered the soil, and a large number of pegs have not yet entered the soil. It is necessary to channel through the rows without damaging roots and to hill without pressing the vines, effectively promoting the normal development of pegs already in the soil and creating conditions for the middle and upper pegs to enter the soil.

2. Timely watering and drainage. As the saying goes, “when the soil is dry, pegs do not penetrate; when the soil is wet, pods do not fill.” That is to say, in the middle and late stages of peanut growth, the soil surface should be kept “dry and wet alternately.” From full flowering to the full pod stage, if there is excessive rainfall or poor drainage, and the soil moisture content exceeds 80% of field capacity, soil oxygen deficiency will affect root or pod development and cause a large number of rotten pods. If waterlogged during this period, the rate of rotten peanuts increases, and the average yield decreases by about 30%. Therefore, for waterlogging-prone plots, drainage ditches should be cleared in time so that light rain does not cause waterlogging and heavy rain does not cause disaster.

3. Spraying trace element fertilizers and preventing premature senescence

1. Spraying trace element fertilizers. Trace elements play a role in peanut growth and development that many other elements (such as nitrogen, phosphorus, potassium, etc.) cannot replace. Once a certain trace element is lacking, corresponding deficiency symptoms will appear through the external morphology of the plant. Peanuts are relatively sensitive to trace elements such as iron, molybdenum, boron, and calcium, especially iron. Planting peanuts in alkaline soil is prone to iron deficiency, showing symptoms of yellowing and whitening leaves. If iron fertilizer is sprayed in time, the peanut leaf color can turn from white to green within a few days, with an obvious yield-increasing effect. According to experiments, spraying 0.4% ferrous sulfate once each at the full flowering stage and pod filling stage of autumn peanuts can increase yield by more than 10%. With sufficient zinc supply, peanuts grow vigorously with strong plants and lush leaves. If zinc fertilizer is added to iron fertilizer and sprayed together, the yield-increasing effect is even better.

2. Do not overuse chemical control. Because large amounts of chemical control agents are sprayed, such as large amounts of paclobutrazol, some peanut plots show premature senescence before the plants are old. Therefore, for peanuts in fields with insufficient base fertilizer or high-yield fields, spraying foliar fertilizer at the middle and late stages of peanut growth is an effective measure to achieve high-quality and high-yield peanuts. From 30-50 days before harvest, spray a mixed solution of 1% urea plus 0.5% potassium dihydrogen phosphate on the leaves, spraying 50 kg of fertilizer solution per mu each time. Spray once every 10 days, generally 2-3 times, which has an obvious effect on improving leaf photosynthetic capacity and promoting full pods.

4. Timely prevention and control of diseases and insect pests. To control underground pests such as white grubs, use 200 ml/mu of 48% chlorpyrifos emulsifiable concentrate, dilute with an appropriate amount of water, and mix evenly with 1 kg of fine sand, or use 3 kg/mu of 5% phoxim granules, mix evenly with 1.5-2.5 kg of fine dry soil, and bury it near the peanuts while hilling to welcome peg penetration.

To control pests such as cotton bollworm, bridge worm, and tobacco cutworm, when there are more than 30 larvae (eggs) per 100 hills, and 30% are rice-yellow and a few have already hatched, before the larvae reach the 3rd instar, spray the leaf surface with Bacillus thuringiensis, or spray 3.2-4.0 g/mu of high-permeability abamectin mixed with 60-75 kg of water.

For the control of peanut leaf spot disease, spray 150 g/mu of 75% chlorothalonil, and at the same time also control peanut rust; 100 g/mu of validamycin or 15-20 kg of sulfur suspension concentrate can also be sprayed on the leaves.

5. Timely harvest. When the leaves on the upper fruiting branches of peanuts turn yellow, most of the middle leaves have already fallen, the shell reticulation is clear, and after opening the pod, the sponge layer inside the shell has a black luster, the seeds are plump, the seed coat is reddish, and the rate of full pods reaches 85%, it indicates that the peanuts are mature and must be harvested in time. Harvesting too early or too late will reduce quality and yield.