How to fertilize to green Chinese onion?
Publish Time: 2016-04-12 Origin: Rech Chemical Co. Ltd
Green Chinese onion is a crop that needs large number of fertilizers, and is sensitive to N fertilizer. In the leaf growth period, green Chinese onion absorbs more N fertilizer than K fertilizer, the proportion is 1:0.9, but in the cauloid period, it absorbs more K fertilizer than N fertilizer, the proportion is 1.2:1. For every 1000kgs of green Chinese onion, it needs to fertilize 2.7-3.3kgs of N fertilizer, 0.5-0.6kgs of P fertilizer, and 3-3.7kgs of K fertilizer, the proportion for nutrient absorption is 5.45:1:6.09. And the output will be decreased if P fertilizer deficiency occurs in the seedling period. Proper secondary and micro-nutrients such as magnesium sulfate and manganese sulfate are needed if 21kgs of N fertilizer, 5kgs of P fertilizer and 11kgs of potassium oxide fertilized.
Seedling growth fertilizer: Fertilize decomposed organic fertilizer in the seedling plot, 2000-3000kgs/ 667㎡， 40-60kgs of calcium superphosphate, and plough deeply, mix with soil equally and then make plots. Watering once before freezing-up to make security of seedlings in winter. Broadcast horseshit for 1cm depth to be antifreezing after some days. Top dress 10-15kgs of ammonium sulfate and 5-7kgs of urea.
Base fertilizer: It must fertilize enough base fertilizer before planting, and mix broadcasting and furrow application together. Generally, 4000-5000kgs of animal manure is needed for every 667㎡，deeply plough, and mix with soil completely, smooth the soil and ditch according to line spacing, apply 100-150kgs of cake fertilizer, or 1000kgs of night soil, then mix again and scarify and plant. Top dressing: Seedling grows very slowly after planting, but it will stage into a prosperous growth period when the weather turns cool. Under such situation, new leaves are instead of old leaves and grow fast. Top application is needed timely after autumn begins, and use organic fertilizer together with quick-acting chemical fertilizer. The first top application needs 4000kgs of mix fertilizer such as weeds and soil on the ridges, or 150kgs of cake fertilizer, shallow plough and watering once. The second top application is fertilized after in 15 days; fertilize 750kgs of night soil or 20-25kgs of ammonium sulfate, 10-20kgs of calcium superphosphate and 10-20kgs of potassium sulfate. Ridging with deep hoe and watering after fertilizing. The third top application is made after 25-30 days, fertilize 15-25kgs of ammonium sulfate or 7-10kgs of urea, watering and ridging after top application.
Secondary and micronutrient fertilizer such as Ca, Mg (magnesium sulfate), B, Mn (manganese sulfate) are needed for growth of green Chinese onion, and fertilize Ca, B and Mn fertilizer will make onion stalk long and thick and high yield.