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How Long Does Fertilizer Last In Soil? Revealed!

How Long Does Fertilizer Last In Soil? Revealed!

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A lot of variables play when it comes to fertilizer use.

One can use too much or too little, or they can get things just right and have a genuinely prolific garden.

How much or little you water will affect how long fertilizer lasts. For example, heavy rains and overwatering can leach fertilizer from the soil very quickly.

On the other hand, very dry weather means fertilizer will remain longer.

Especially if the area, such as pastures and outlying plants, is not watered regularly and has received little rain during the growing season.

Whether you are fertilizing your garden, potted plants, or lawn, follow along and learn how long fertilizer lasts in soil.


How long does fertilizer last in soil?

The length of time fertilizer remains on these areas of your property depends on how much rain you get and if it is watered regularly and also the type of fertilizer you use. Excessive rain will leech soil nutrients. Slow-release fertilizer will remain in the soil longer than liquid fertilizer. It’s even possible that you’ll need to fertilize more than once yearly. For potted plants fertilizer lasts 30 to 90 days in the soil.


How Long Fertilizers Last In Gardens

Again, weather, watering practices, and the type of fertilizer you use are all factors in how long it will last. If you amend your soil with compost and organic material, you may not need to add fertilizer.

To know the pH and nutritional composition of your soil, have it sampled.

Phosphorous (P) is not an issue because you only lose it when you harvest your plants. The same goes for potassium (K), and pH plays a role in how well your plants uptake these nutrients.

Nitrogen is a little more difficult to gauge and can be lost from the soil more quickly than the above-noted minerals. Therefore, the source of nitrogen is a factor in its longevity in your garden.

The other three nutrients you need are oxygen, hydrogen, and carbon, all of which come from water and air.

The three other nutrients that your plants require are sulfur, magnesium, and calcium.


How Long Fertilizers Last In Containers

Potted plants require fertilizer every 30 to 90 days, depending on whether you use liquid or granulated fertilizer or compost tea.

Just as in your garden, liquid fertilizers will leach from the soil more quickly than granular products.

When using granulated fertilizer, be sure to water your plants until water flows freely from the bottom. Overfertilizing can leave salt deposits on top of the soil, which could eventually cause plant wilt and illness.

Because of the limited space for roots and dirt in a pot, the soil can only hold enough nutrients for a short time.

Gardeners can have the same issue with raised beds unless the beds are started with a sufficient amount of organic matter mixed with the soil.


Do Different Plants Require Different Fertilizers: The Answer

Yes, they do, as different plants use minerals at different rates. For example, some need more nitrogen than potassium and vice versa.

When planting your garden, potted plants, or blueberry bushes, learn what nutrients each plant needs before planting.

By doing so, you will know what you need to add to your soil, or to eliminate, to get the best productivity from your plants.


What Fertilizer To Use: The Must-Knows

You know what fertilizer to use by learning what your plants require.

Once you know this, you can amend your soil accordingly, or you can choose the fertilizer that you think will best suit your application.

Many organic gardeners make organic tea by mixing water with organic materials. This process produces a mixture that they add to their plants as you would any liquid fertilizer.

Little more than manure and water, there are many recipes out there that organic gardeners have spent years developing that work very well.


Types Of Fertilizers

Fertilizer comes as a liquid, granulate, time-released granules, and organic. There are others, but this collection includes what you will find at the local coop or feed store.

You can even find organic tea there, or you can make your own.


What The Numbers And Letters Mean

When buying fertilizer, you will see three letters proudly displayed on the bag. They are N, P, and K.

Indicating nitrogen (N), phosphate (P2O5), and potash (K2O). The numbers indicate each nutrient’s percentage concentration. 

Thus, 10-10-10 means that the fertilizer contains 10 percent of these nutrients, while 20-20-20 would indicate the product has 20 percent of each nutrient.

Your plants require all of these nutrients in varying amounts. Each nutrient plays a role in your plants’ health.


What Nutrients Do Each Plant Needs

Nitrogen is what gives your plants their green leaves and growth. Phosphorus helps grow a robust, healthy root system, and potassium encourages hardiness and vigorous growth.

Each nutrient plays a role in the health of your plants, so getting to know their needs will help you give them the nutrition they need.


Frequently Asked Questions About How Long Fertilizer Last In Soil


How do I know when to apply fertilizer?

It would help if you fertilized your lawn and garden beds heavily in the fall and lighter in the spring. That is if they need it. Having your soil tested before an application is a good practice, especially when fertilizing and gardening large areas.


What happens when you over-fertilize?

Over-fertilizing plants can be as bad as not giving your plants enough nutrients. But, on the other hand, too much of a good thing can cause salt build-ups in the soil and an imbalance in the soil of microorganism populations.