For eggplant greenhouses of different ages, fertilization methods vary

Greenhouse eggplant is a heavy-feeding crop with a long growing period, a long fruiting period, high yield and high fertilizer demand, so sufficient base fertilizer must be applied before planting.

The amount of fertilizer applied should differ between old greenhouses and new greenhouses. This is because old greenhouses have more residual nutrients in the soil than new greenhouses, so new greenhouses need more fertilizer than old ones. According to measurements, most old greenhouse soils have excess nitrogen, accumulated phosphorus and insufficient potassium. Under normal circumstances, a new greenhouse is given 6000 kg of organic fertilizer per mu, while an old greenhouse can reduce that amount and add 20-30 kg of potassium sulfate.

Organic fertilizer must be fully decomposed. Organic fertilizer and potassium fertilizer should be broadcast evenly, then turned into the soil, taking care that the manure is fully mixed with the soil to prepare for planting.

From planting to flowering and fruit set, fertilizer is generally not needed, and cultivation management is mainly temperature management. At the flowering and fruit-setting stage, thicker eggplant stems, short internodes, larger leaves, large flower buds, glossy leaves and a well-developed root system indicate a high-yielding appearance; if the eggplant stems are thinner, the leaves small and pale, and the flowers small, it shows that the plants are weak, often caused by fertilizer deficiency. At this time, 0.2% urea or potassium dihydrogen phosphate can be sprayed on the leaves.

After the first eggplant fruit has set, apply 20 kg of ammonium sulfate per mu, by furrow or hole application. After the first eggplant fruit is harvested, 15 kg of urea or 1000 kg of diluted manure water can be applied with irrigation water.

When the second-layer eggplant fruits enter the harvest period, it indicates that the plants have entered the peak fruiting period. During this period, water should be given every 7-8 days, and fertilizer should be applied with every other watering, alternating organic fertilizer and chemical fertilizer, with an application rate of 15-20 kg of ammonium sulfate or 1000 kg of diluted manure, and after the second-layer eggplant fruits are harvested, 10 kg of potassium sulfate should be added to supplement the shortage of potassium in the soil. Wanguo