Close this search box.

Unlocking the Secrets of Cotton Fertilizer: A Comprehensive Guide

Unlock the secrets to boosting cotton yield with our guide on optimal fertilizer use for healthy growth and bountiful harvests.

Cotton is a type of shrub plant that is cultivated for fiber and seeds. Some of the popular cotton types are upland cotton, herbaceous cotton, and cotton trees. This dicotyledonous plant thrives in warm and humid regions. The plant has a low tolerance to frost and hence can only be cultivated in warm regions or indoor greenhouses. 

It requires fertilizers rich in nitrogen, potassium, and phosphorus with zinc and calcium. The lack of any of these minerals may lead to small plants with little to no bolls(fibrous part of the plant).

If you’re planning to grow cotton or wish to take cotton harvest to a new level, we’ll discuss the best ways for cotton fertilizer application. Keep reading to learn more.

How to Grow Cotton from Seed?

How to Grow Cotton from Seed

The perennial cotton plants can be grown using seeds. Even when they are perennial they can be grown throughout the year, keeping care needs in mind. The best quality seeds will always generate good yields under the right circumstances.

Cotton is generally sowed in the spring season and harvested by the autumn season right before the frosty winter hits. Preparation of soil and managing the nutrients is highly essential when farming cotton.

Cotton Climate Requirements

Cotton plants like temperatures between 70 to 100 degrees F. The temperature has to be warm right from the seedling stage as the germination may decrease in low temperatures. A temperature drop of ten degrees can reduce the yield. That’s how sensitive cotton crops can be.

Another essential requirement is maintaining the humidity levels. Too heavy and frequent rain can destroy the crop. Due to this reason, it is sown and grown in summer and harvested right before the cold hits.

Cotton Soil Preparation and Needs

Cotton plants need well-drained and loamy soil to grow. The soil must have organic matter and be rich in nitrogen, calcium, and phosphorus. To drain the soil well, a slope can be given to the field for best results.

The field can be prepared in the autumn season after the harvesting of the previous batch. Start plowing up to 14 inches to remove solid soil and maintain a soft texture. Make sure you take measures to prevent weed growth, as cotton does not thrive with weeds in the same field. 

What are the Nutrient Recommendations for Cotton Plants 

Nutrient Recommendations for Cotton Plants

Each stage of plant growth requires a certain amount of fertilizer to give the desired yield. Keeping this in mind, fertilizer application can be spanned across the growing stages to get high produce. We’ll discuss the nutrient demands of the cotton plants and how their deficiencies may impact the growth and yield. 

Nitrogen Requirements

Nitrogen impacts the yield of the crop; thus, it should be used in the right amount. However, the requirement will depend on the type of soil and its nutritional profile. According to the Texas AgriLife Extension Service, use 50 lbs on one hectare of land. 

Nitrogen Deficiency 

If the plant does not get ample nitrogen, the bolls will reduce in quantity as well as weight. The cotton seed quantity will also decrease due to nitrogen deficiency. This makes nitrogen essential during the sowing and flowing stage. 

The plants will have a smaller height with yellow leaves. Moreover, the leaves and stems can develop a reddish tint.

Calcium Requirements 

The cotton plants may take up to 27 to 62 pounds of calcium per bale. Calcium helps in root and leaf development. In addition, using calcium nitrate will boost enzyme activity while neutralizing acids in the plant and soil. Calcium aids in reducing nitrate-nitrogen so that the plant can grow to a sufficient height. 

You may add micronutrients such as zinc, iron, and boron to the soil with the help of fertigation. You may use calcium nitrate with phosphorus for fertigation. These fertilizers will react to form calcium A phosphate, which will be insoluble. Overall, calcium nitrate works as a quick fertilizer during the cultivation season. 

Signs of Calcium Deficiency 

Due to a lack of calcium content, the plant may have a poor root system. The roots may start to rot and turn black, not supporting nutritional requirements. This can result in gelatinous leaves and low-volume bolls. 

To improve the calcium content, gypsum, and rock phosphate may be added to the soil. 

Potassium Requirements

Potassium makes the bolls more fiber-rich and strong so that they can survive till the harvest season from August to October. Moreover, the need for potassium will increase during the early boll stage.

According to the International Potash Institute studies, add 3-5 kg potash per hectare to the cotton plants. Of course, the quantity will be altered as per the soil nutrient profile. However, cotton has high potassium requirements during the sowing and growing stage. Using an NPK fertilizer is the best way to provide the right nutrients.

Potassium deficiency in the Crop

The potassium deficiency may show up as high moisture in the soil, hence increasing the surface temperature of the leaves. Besides, the yield may reduce with smaller bolls and less lint in the bolls. In addition, the strength of the fiber will also decrease, leading to wilted crops. 

Fertilizing Cotton Plants

Fertilizing Cotton Plants

Before you start fertilizing the plants, consider the weather and soil type of your region. Do a soil test to learn about the minerals in the soil and the ones that are missing. Diagnosing the nutrient deficiencies will ensure you use the right fertilizers in appropriate quantities. 

Cotton plants require nitrogen and potassium to grow. The amount of nitrogen needed will be double the required potassium. So you can opt for N-P-K fertilizer in a 20-10-10 ration. You may add 200 kg of this NPK fertilizer per hectare of land during the sowing season. Add the same amount of fertilizer in the flowering season in the late spring or early summer season.  

When using ammonium nitrate, add 250 kgs during the sowing stage. Combine this with 181 kg NPK (0-46-0) and NPK (0-0-50) fertilizer per hectare of the land. You may divide the application amounts for a convenient fertilization. Always consider the current state of the soil, weather, and crop needs and alter the quantities as needed. 

Foliar Feeding and Fertilization Schedule for Cotton Plants

The cotton plants receiving adequate fertilization will produce fibrous cotton bolls.

Vegetative Growth

Adding additional nutrients to the soil can ensure the plants don’t wilt during the resting period. It may also help under high-stress conditions. Make sure you add N, P, and K fertilizer as per the crop and land. If you are using a spray, apply 20-25 grams per liter of water between rest and growing period at intervals of a week or two. The result will be better plant quality and squares in the field. 

Improving Boll Development

The next crucial stage is to encourage the boll development and its weight. Apart from fertilization, reducing pests and eliminating diseases from the bolt is crucial. Use potassium along with boron and nitrogen to get better lint in the boll and deter pests. 

A potassium spray of 20 grams in a liter of water with 0.1% borax will work great for boll weight. Also, consider the fertilizer instructions on the packaging when using sprays or granular fertilizers. 

Plant Growth and Rejuvenation 

After the first phase of vegetative growth, you can revive the same crop for the second and third seasons. Use potassium-rich fertilizer over the crop in a ratio of 15 grams to one liter of water. Do this after the bolls have started to grow and are in the fiber-developing stage. Continue using 2-3 sprays at 8-10 days intervals. This schedule can also be followed when flowering has begun in the plants. 

Fertilizer Schedule (kg/ha)

Here’s a recommended schedule for cotton plants: 

Basal fertilization: You may start the basal fertilization of phosphorus in the form of SSP(375 kg), zinc sulfate (50 kg), and organic farm yard manure (10-12 tons). Make sure not to use zinc sulfate with SSP, as they may react together.

First Top Dressing: The first top dressing will be 10 to 15 days after the sowing. Use about 30 kgs of Calcium Nitrate.

Second Top Dressing: Use 90 kg Urea and 35 kg Muriate of Potassium (MOP) 30 days after sowing.

Third Top Dressing: Use 35 kg Muriate of Potassium (MOP) and 100 kg urea 60 days after sowing.

Fourth Top Dressing: After 90 days of sowing, use urea and Muriate of Potassium in the same quantity as the second and the third dressing. 

Wrapping Up

It is easy to grow cotton plants in humid and warm climates with the right fertilization routine. The plants don’t do well in the frosty region. One way to get the ideal temperature is to grow plants indoors in frosty months. 

Based on the above-mentioned fertilizer needs, you can ensure a good yield of cotton crops. A high-quality NPK fertilizer with magnesium will give the essential nutrients to the plants. Source your fertilizers from a certified fertilizer seller for effortless plant care and high yield. 

Lasted Articles for You

Assortment of succulent plants in various pots ideal candidates for top indoor plant fertilizers to promote healthy growth

Top 10 Fertilizers To Feed Your Succulents

Explore the top 10 fertilizers for succulents, enhancing growth, and boosting plant health with optimal NPK ratios.

Child crouched on grass holding colored pencils symbolizing the planning phase of a fertilization timeline

When to Fertilize New Sod?

Discover the optimal timing and techniques for fertilizing new sod to promote strong root growth and a lush, vibrant lawn.

Person holding a yellow watering can preparing to apply fertilizer on wet grass

What Happens If You Apply Fertilizer to Wet Grass?

Discover why applying fertilizer to wet grass is harmful and get tips for proper lawn fertilization techniques.