What kind of fertilizer is good for alfalfa base fertilizer (base fertilizer application method)

Alfalfa base fertilizer effect

A large number of rhizobia can form at the roots of alfalfa, and rhizobia have the function of fixing free nitrogen in the air. Therefore, alfalfa fields generally do not need to apply a large amount of nitrogen fertilizer. However, applying a small amount of nitrogen fertilizer as base fertilizer before the nodules are formed in the alfalfa seedling stage will help promote the formation of nodules and the growth of seedlings.

Alfalfa fertilizer selection

Nitrogen fertilizer, phosphorus fertilizer, and potassium fertilizer are called three-element fertilizers. They play different roles in the growth and development of alfalfa. Therefore, the base fertilizer can be selected from fertilizers containing nitrogen, phosphorus, and potassium.

How to apply alfalfa base fertilizer

Alfalfa has a shallow root system, so usually the tillage depth is about 15 cm. Then human and animal manure is applied as base fertilizer, and the ridges are made into 20 cm high ridges and about 1.5 meters wide to increase drainage. The ridge surface is then leveled and sowing can begin.

In order to reduce the problem of uneven emergence of alfalfa, you need to select strong and full seeds before sowing, remove shriveled and bad seeds, and soak the seeds in warm water at 55 to 60 degrees for 5 minutes, and discard the floating seeds on the water surface.

How much base fertilizer should be used for alfalfa

1. For low-fertility plots, the standard is that the soil contains less than 1.2% organic matter, less than 70 mg/kg alkaline nitrogen, less than 15 mg/kg available phosphorus, and 80-120 mg/kg available potassium. For low-fertility soil, apply 3-4 kg of nitrogen fertilizer, 6-8 kg of phosphorus fertilizer, 8-10 kg of potassium fertilizer or 45-55 kg of alfalfa fertilizer per mu.

2. For plots with higher fertility, the standard is soil containing more than 1.7% organic matter, more than 120 mg/kg of alkaline nitrogen, more than 30 mg/kg of available phosphorus, and more than 110-130 mg/kg of available potassium. For highly fertile soil, apply 2 kg of nitrogen fertilizer, 4-6 kg of phosphorus fertilizer, 6-8 kg of potassium fertilizer, or 35-45 kg of alfalfa fertilizer per mu. You can also apply 1500-2000 kg of farmyard manure per mu.

How to apply fertilizer to alfalfa

1. Apply fertilizer immediately after alfalfa is harvested and before regeneration, and avoid contact of fertilizer with wet leaves to avoid burns. Apply fertilizer after the first mowing to promote regeneration after the second and third mowing. Apply fertilizer in early September to improve the cold resistance of alfalfa. If the amount of fertilizer applied in any year exceeds 38 kg per mu, do not concentrate the top dressing.

2. Do not use foliar application of large amounts of fertilizers to alfalfa to avoid salt poisoning, which will result in decreased nutrient absorption.