01/11/2021 | Agriculture and Farming | 9 MINUTE READ

Determining the Optimal Liquid Fertilizer for Agriculture

Liquid fertilizer refers to any kind of liquid solution that’s provided to plants as a form of food. These fertilizers are able to provide plants with the food that they need to survive via a couple of different delivery methods. You can either spray the fertilizer onto the leaves of the plant or place the fertilizer into the soil, which will result in the roots of the plant absorbing the fertilizer.
While liquid fertilizers are primarily used for feeding individual plants, these solutions are also able to provide a boost to the growing area that numerous plants are situated in. If you’re searching for ways to increase the amount of nutrient content that’s in the soil or similar type of growing medium, you can apply liquid fertilizer to the area. This article offers a detailed look at how to identify the best liquid fertilizer for your agricultural needs.

Key Takeaways:

  • Liquid fertilizers helps provide plants with the food they need to survive.
  • Choosing the right liquid fertilizer for your plants is important because if it is incorrect it could possibly damage or even kill your plants.
  • The NPK balance stands for nitrogen, phosphorus, and potassium nutrients that your plants must have an even balance of to be considered healthy. Additionally, checking the plants ph levels regularly can help you decipher if there is a problem in the soil.

Choosing Your Ideal Liquid Fertilizer

liquid fertilizerBefore you select the liquid fertilizer that you believe would be right for your plants, it’s important to understand that different options should be used for different growing areas and plants. If you select the wrong fertilizer, it’s possible for the plants to be damaged or killed. Try to stay away from highly concentrated solutions as well.
The most important thing that you should look at is the NPK balance of the solution. The NPK balance refers to the nutrients of nitrogen, phosphorous, and potassium. All three of these nutrients are necessary for the creation of any liquid fertilizer. However, every plant requires a different concentration of the NPK nutrients, which you should keep in mind before you begin to use liquid fertilizer.


Nitrogen is an element that is highly beneficial for the growth of a plant. When fed to plants, this substance mainly promotes leaf growth, which is why high amounts of nitrogen are needed for leafy vegetables to survive. When a plant isn’t getting enough nitrogen, the green leaves will start to yellow and become discolored. It’s also possible for a pinkish tint to develop on the leaves of plants that aren’t getting enough nitrogen.
You can determine that your plants aren’t receiving enough nitrogen if the leaves yellow after the plants have been heavily watered. Nitrogen is considered to be very soluble, which means that the substance can be washed out of your soil in the event that you over-water the plants. If you want to effectively reduce nitrogen-deficiency in your plants, consider using feeds that are rich in nitrogen, which include nettle-based feeds and grass clippings.


Phosphorous is another important chemical element that most plants require an ample amount of to survive. This particular element is able to assist with the growth of roots and shoots. While it’s rare for plants to be deficient in phosphorous, this issue can occur after heavy rains or if the plants are situated in clay soil. The primary signs of a phosphorous deficiency include slowed growth, the foliage becoming dull, or the leaves turning yellow. In order to correct this problem and provide your plants with the nutrients that they require, think about adding blood and bone meal or fish to your feeds.


Potassium is another essential nutrient that’s necessary for the control of water uptake as well as for the photosynthesis process. Since plants need to use photosynthesis to convert sunlight into food and fuel, it’s important that every plant receives the amount of potassium that they require. Potassium helps to promote the healthy fruiting and good flowering of various plants. When plants aren’t receiving the amount of potassium that they require to survive, the leaves will have purple or yellow tints to them. It’s also possible that the plants won’t flower well or that the edges of the leaves will turn brown.
Potassium deficiency is more common when using sandy or chalky soils. This issue can also develop after heavy rains. If you want to properly correct this issue, consider using organic tomato feeds or feeds that are based on other sources of potassium. For instance, you could use banana skins as the basis for your feed. Once introduced to the plants, it shouldn’t be long until any signs of deficiency lessen, which should result in healthy plants.

PH Levels

When you’re searching for the ideal liquid fertilizer for your plants, it’s essential that the pH levels of the fertilizer are correct. The reason that the fertilizer must have a specific pH level is because the soil will already have its own pH. In the event that the pH levels of the fertilizer are significantly different than the soil levels, the fertilizer could cause the pH levels in the soil to change once applied, which could worsen the health of your plants. If the fertilizers are too acidic or alkaline, the plants may be unable to grow properly.
An example of a fertilizer that can cause changes to the pH of your soil is a potash liquid fertilizer. This type of fertilizer is commonly used to balance soils that are considered to be highly acidic. While different plants require different pH levels in the soil, the optimal pH range for plants is usually between 5.5-7.5. If the pH of the fertilizer is below 5.5, this would be considered an acidic pH. Anything above 7.5 would be considered alkaline. Consider measuring the pH of your soil before choosing a liquid fertilizer. If the pH is already at the optimal levels, you likely wouldn’t need to use a potash liquid fertilizer.

Using Sustainable Materials

Likely the top option when you’re looking for the best fertilizer is to make your own with sustainable materials. The reason why you should try to use natural fertilizers as opposed to chemical ones is because the chemicals that are used in store-bought fertilizers are harmful to the environment and add unnecessary pollution to the world around you. Organic gardening is simple to perform as long as you take the time to research what this type of gardening involves.
If you opt for creating your own fertilizer at home, the most sustainable method of making this fertilizer is by sourcing the ingredients as close to your home as you can. For instance, materials that are obtained from your garden would be ideal for any natural liquid fertilizer. If you don’t currently have a garden, all of the ingredients that are needed for a fertilizer should be in your general vicinity. In many cases, natural fertilizers will allow plants to produce more and grow stronger over a lengthy period of time when compared to chemical-based fertilizers.

Two Main Types of Liquid Fertilizer: Mineral and Organic

liquid fertilizerThere are two primary forms of liquid fertilizers, which include mineral fertilizers and organic fertilizers. Different plants require different fertilizers. Mineral fertilizers are processed with chemicals, which ensures that these fertilizers are able to provide plants with the exact quantities of nutrients that they require. As for organic fertilizers, they are made directly from livestock manure, plant residue, or similar natural sources. However, the amounts of nutrients may not be as precise as you would like when you opt to use an organic fertilizer.
Keep in mind that fertilizers can come in a variety of different forms, which extend to liquid fertilizers, granular fertilizers, and capsule-based fertilizers. If the plants that you’re growing require an exact concentration of nutrients, you may want to use mineral fertilizers. On the other hand, organic fertilizers are great for the environment and will provide similar results for the growth and health of your plants.

Best Types of Liquid Fertilizers

While there are many different liquid fertilizers that you can use for your plants, the following are a few of the best fertilizers on the market.

Jack’s Classic All-Purpose Solution

Jack’s Classic all-purpose solution is a high-rated fertilizer that’s ideal for gardens. This mineral fertilizer is versatile and can be used on outdoor and indoor plants, which extend to roses, evergreens, and shrubs.
The exact NPK ratio of this fertilizer is 20-20-20, which allows the plants to receive an equal amount of each nutrient. Once applied, this specific fertilizer is designed to work for up to four months before it needs to be re-applied. The only issue with this fertilizer is that it can reduce the pH of your soil.

Espoma All-Purpose

The Espoma all-purpose fertilizer is a natural fertilizer that is beneficial for the environment and can be used on a wide range of plants and trees. This particular solution has been enhanced with bio-tone microbes, which makes it effective at promoting the healthy growth of plants.
The formula that’s used within this fertilizer is designed for a slow release, which means that the fertilizer doesn’t need to be applied on a regular basis. Other than the strong odor that comes with this fertilizer, there are hardly any issues to be concerned about with this Espoma all-purpose fertilizer.

Miracle-Gro Water-Soluble Plant Food

The Miracle-Gro water-soluble plant food may be the best all-around fertilizer for your plants. This is a mineral fertilizer that can be used on houseplants, vegetables, and trees. The water-based formula that’s used in this fertilizer must be dissolved before it can be applied to plants.
Once dissolved, make sure to apply the feed to your plants every 1-2 weeks. The NPK ratio of this fertilizer is relatively unique at 24-8-16. Keep in mind that this fertilizer doesn’t contain iron, which may be a problem with modern varieties of petunias and similar plants.
The liquid fertilizer that you choose for your plants can be the difference between healthy plants that grow quickly and plants that are unable to provide you with the results you’re looking for. If you’re mainly focusing on planting and growing tomatoes, certain fertilizers are designed specifically to accommodate and enhance the growth of tomatoes. No matter what types of plants you’re growing, you should be able to find the optimal liquid fertilizer for your needs.

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Posted by Sensorex on January 11, 2021

Sensorex is a global leader in the design and manufacture of quality sensors for water quality and process applications. The company offers more than 2000 sensor packages for pH, ORP, conductivity, dissolved oxygen, free chlorine, chlorine dioxide, UV transmittance and other specialty measurements, as well as a full line of sensor accessories and transmitters. Its expert technical support engineers solve analytical sensor challenges with custom designs and off the shelf products.

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