How to Apply Base Fertilizer When Repotting Flowers? These Precautions You Need to Know

Efficient and simple repotting and transplanting techniques can greatly increase the survival rate of plants.How should base fertilizer be applied when repotting? What are the precautions for applying base fertilizer when repotting flowers?Let's find out together.

1. What is base fertilizer?

Base fertilizer is the foundational fertilizer, referring to the fertilizer applied at the bottom of the pot when repotting or changing the soil of potted plants. It mainly supplies the nutrients needed throughout the entire growth period of the plant, creates good soil conditions for crop growth and development, and also has the effect of improving soil and building soil fertility.

2. How is base fertilizer applied?

Applying base fertilizer generally needs to consider four aspects: the type, quantity, fertilizer variety, and depth of application of the base fertilizer. From the perspective of type, organic fertilizers (including farmyard manure, stable manure, green manure and cake fertilizer) are most suitable for use as base fertilizer; in addition, nitrogen, phosphorus, potassium and micronutrient fertilizers are all suitable as base fertilizer. This is the most basic step in fertilization and is crucial for crop growth and development, especially at the seedling stage and the early stage of crop growth. To determine the amount of base fertilizer applied, especially the amount of chemical fertilizer applied, the level of soil fertility must be considered. In soil with organic matter below 1.2%, more than 3 cubic meters per mu of organic fertilizer should be applied. When the available nitrogen, phosphorus, potassium and trace elements in the soil fall below the effective critical value for crop fertilization, these fertilizers should first be chosen for base application, especially since crops need more phosphorus fertilizer in the early stage. The specific amount of various fertilizers used as base fertilizer can be determined by referring to comprehensive factors such as local multi-year field fertilizer efficiency test results and target yield. Generally, on high-fertility soil, about 30% of the nitrogen fertilizer amount is applied as base fertilizer, while on medium- and low-fertility soil, 50%-70% of the nitrogen fertilizer is used as base fertilizer, while phosphorus, potassium and micronutrient fertilizers should be applied as base fertilizer all at once as much as possible. From the perspective of fertilizer variety, ammonium bicarbonate among nitrogen fertilizers; ordinary calcium superphosphate, diammonium phosphate, calcium magnesium phosphate and triple superphosphate among phosphorus fertilizers; potassium chloride, potassium sulfate and plant ash among potassium fertilizers; and zinc fertilizer and manganese fertilizer among micronutrient fertilizers are all suitable as base fertilizer.

In terms of depth, base fertilizer should generally be applied within the entire plough layer, that is, at a depth of 15-20 cm. For organic fertilizer, nitrogen fertilizer, potassium fertilizer and micronutrient fertilizers, they can be mixed and evenly spread on the soil surface, then immediately ploughed into the soil, so that the fertilizer is evenly mixed with the soil of the entire plough layer, which is conducive to the absorption and utilization of nutrients by different root layers of crops. Because phosphorus fertilizer has poor mobility and is easily fixed after being applied to the soil and loses its effectiveness, it should be applied in two layers, upper and lower, when applied as base fertilizer, that is, the lower layer applied to a depth of 15-20 cm, and the upper layer applied to a depth of about 5 cm. The upper layer mainly meets the phosphorus demand of crops at the seedling stage, and the lower layer supplies phosphorus nutrition for crops in the middle and later stages of growth.

3. What are the precautions for applying base fertilizer when repotting flowers?

First, when applying base fertilizer to plants, avoid direct contact between the fertilizer and the plant roots, so as to prevent burning and cause unnecessary damage;

Second, do not apply too large an amount when fertilizing. Generally, for woody flowers with a pot diameter of 40 cm, the application amount is: 200-300 grams of decomposed organic fertilizer or about 20 grams of chemical fertilizer;

Third, the fertilization methods include hole application and bottom application. Hole application means digging a hole in the pot, putting the fertilizer into the hole and then covering it with soil; the depth is generally more than 5 cm. Bottom application is generally carried out in combination with repotting and changing soil. After taking the plant out of the pot, first put a layer of soil at the bottom of the pot, then place the fertilizer on top of the bottom soil, then put a thin layer of soil, and then plant the plant. When planting, be sure to firm or tamp the soil, water thoroughly, and then carry out normal care. If the plant has had a lot of soil removed, place it in a cool place for care; plants that have not had soil removed can be cared for according to the plant's habits.