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What is the Best Fertilizer for Onions?

Onion farming can be a lucrative venture if done right. Most people make the mistake of buying just any type of fertilizer they find on the internet. However, despite what the product says about its nutrient composition, if it does not contain a high amount of nitrogen, then it will not be of much use. The best chemical composition is that which contains nitrogen, Sulphur and phosphorous.   


Why Do Onions Need Nitrogen?  

A nitrogen-based fertilizer will increase the size of the onion leaves and as a result, this will increase the bulb scales which will make it bigger and heavier. For a market that uses weight as a costing factor, bigger onions might increase the income of your onion business. However, nitrogen fertilizer alone will not result in optimal yields. It is for this reason why you also need to buy a fertilizer whose chemical formulation also includes sulphur and phosphorus.  


Before you plant, you need to first prepare the land for onion fertilizer application, by having a soil test done. If the soil has low natural phosphorus levels, then you will need to add phosphorus to help increase yields.  


Do Onions Need Potassium Based Fertilizers?  

Potassium is particularly helpful when it is applied in soils that have very high levels of nitrogen. This is because it helps reduce the risk of the onions rotting while in storage. When planting onions, you need to be extra careful about the chloride levels in the soil. Too much of it can reduce yields and during storage, you might realize that the weight of the onions have reduced.   


Do Onions Need Sulfur Based Fertilizers?  

This question will depend on several factors but the most important is the amount of sulfur in your soil. If your land has high levels of sulfur concentration, then it can be detrimental to your onions. Therefore, you will require a fertilizer that does not contain sulfur. If the soil contains low or zero concentration of sulfur, then you need to add it into the soil because it helps onions increase their nitrogen intake which results in increased yields.   


4 Reasons to Use Organic Fertilizer for Onions  

Before we dive into the technical aspect of organic and industrial fertilizers, let us first understand what organic means. An organic onion foliar spray fertilizer is a solution that is made from organic substances such as animal waste or plant waste. In simple terms, think of manure and compost. So, what are the advantages of using a foliar fertilizer?  


It Improves the Soil Structure  

Unlike industrial chemicals that destroy your soil structure, organic solutions will improve its structure. It will do this by improving the ability of your soil to hold onto water and nutrients. Over time, if your land will become more fertile and productive.  


Its Environmentally Friendly  

When you use a synthetic fertilizer, you are introducing chemical solutions into the soil which may runoff and contaminate natural waterways. As a result, the contaminants will affect marine life.  


Nb: According to research done by the Organic Trade Association, farmers who use organic solutions in their farms increase biodiversity by more than 30%.  


Synthetic Fertilizers Don’t Contain Carbon  

Because they do not contain carbon as part of their chemical make-up, it becomes difficult for microbes to feed. Microbes feed on solutions that contain carbon, nitrogen, potassium and phosphorus. If you care about the environment, then we advise you stick to natural fertilizers.  


Organic Solutions Reduce the Need for Pesticides  

Though most people claim that organic fertilizer is more expensive you need to factor in the cost of pesticides to determine whether this is true or it is all a fallacy. When you use organic solutions, you significantly reduce the number of pesticides that you will spray on your farm. This means, you will have lower costs of production in the long run increasing your profit.  


Onion Fertilizer Requirements  

After you have identified the best fertilizer, it is now time to come up with a suitable and practical onion fertilizer guide. First of all, you need to understand that the size of the bulb depends on the size of the green leaves during maturity; the larger the leaf the larger the ring will be. It is that simple.   


Onion fertilizer requirements start the moment you dig your holes. During planting time, ensure you band phosphorus {This decision must be as a result of a soil test} at least 3 inches below the seed. The reason you are banding it 3 inches below the seed, is for the phosphorus to act as a booster for the seeds to sprout.  


Therefore, your onion fertilizer schedule should start with the farmer making a 3-inch wide trench and then distributing phosphate equally at least per 10-row feet. The phosphate should be covered lightly with soil before sowing your seed. From this stage, you should apply ammonium sulfate or ammonium nitrate at least every 30 days. For the best results, never miss any part of this schedule as the seeds might unevenly sprout.   


Fertilizer Program  

Your plan should always contain lots of nitrogen {Unless otherwise advised by your agricultural officer}. It should be as follows:  

  • Preseeding: Before planting, band phosphorus-rich fertilizer at least 3 inches below the seed.  
  • 3 Weeks After Planting: Apply a nitrogen-based fertilizer at the rate of 1 cup per 20 feet  
  • Every 2- 3 Weeks: Boost the seeds with nitrogen until the neck starts to appear. When you feel that it is soft, do not apply any more nitrogen  
  • Watering: Always water your onions each time you feed them. Do not forget to keep them moist throughout the growing period. Onions will require more water as they approach the maturity stage.  

Disease and Control  

One way to minimize the risk of disease is to use a foliar fertilizer. However, this is not to say that diseases will not affect your onions. Some of the common diseases that might affect your bulbs are purple blotch and blight disease. Other diseases will depend on your geographical location and local climate. Therefore, we advise you to check with your agricultural officer to advise you further.  


If you spot purple lesions on the leaves, then you have purple blotch. Purple blotch is mainly caused by foggy weather and heavy dew. If you spot this disease on your plants you need to act immediately as it can be very destructive for your garden.   


An insect that you need to be aware of is the onion thrip. This insect feeds by sucking juices from the crop leaves. These insects should be controlled using a recommended insecticide.  


Nb: For the safety of your consumers, never use an insecticide within seven days of harvesting.   


So How do you Cure Purple blotch Disease?  

The best cure for purple blotch disease is to prevent it from occurring in the first place. The following tips might be of great help:  

  • Always plant in well-drained soils  
  • If the wind blows from the north, then the onion plants rows should run in the same direction as the prevailing wind  
  • Do not use windbreakers  
  • Use recommended fungicide if the problem persists  

Safi FOLIAR Fertilizer for Onions  

Safi folia is one of the best onion fertilizers in the market today. It is specifically designed to boost water uptake and to stimulate the roots to suck as many nutrients from the soil as possible. The foliar fertilizer has also been proven to increase plant health and yields. To buy the Safi fertilizer for onion, click the link below and enjoy a 20% discount. 


This Post Has 4 Comments

  1. Vijay

    It was very very usefull information and would be more interested in learning in onion cultivation
    Thanks and warmest regards Vijay b Mhaske

  2. marty leido

    the onion needs basal fertilizer before transplant,

  3. marty leido

    30 days after planting what is the best.fertilizer use by onion

  4. lal chand

    useful basic knowledge for onion planting farmers. thanks a lot.

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