How to Organically Lower the pH in Water for Plants

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To the amateur gardener out there, it might seem pretty simple to grow your own plants on your own property. But what you may not have realized is that there is far more to growing your own garden than simply planting seeds and watering them.

There are conditions in the soil that can have a drastic impact on the way that those plants grow. One of those conditions is the acidity of the soil and how those specific plants will react to that level of acidity in the soil itself.

There are ways to lower the pH level of the water you are using, making the water far more suitable for the soil and, therefore, the plants. But before we get there, we need to understand what acidity is, what pH is, and why it plays an important role in the soil we cultivate.

Understanding Acidity

The first step is to know what acidity is and how it impacts the way you grow things. Acidity may sound like a bad thing, but it is actually essential for a lot of life all across the Earth. Acidity determines the quality, characteristics, solubility, and absorbability of things.

Enzymes, which are responsible for just about every biological process in organisms, need acidity to work properly. It has to be the right acidity, however, because even the smallest fluctuation can be deadly to certain enzymes. This is where pH comes into play.

Understanding pH

We have all heard about pH levels before, but do we know what they truly mean and do? The term pH actually stands for pondus Hydrogenii and it indicates a particular solution’s acidity or alkalinity.

These values fall between 0 and 14; a solution with a value between 0 and 7 is an acid and 7 to 14 is alkaline.

For instance, soda and vinegar have a pH value of less than 3. Sap might have something over an 8. Anything with a value of 7 is considered to be neutral; this can be pure water at room temperature.

Tap water tends to actually be a little higher in pH because there is calcium in that water to be accounted for.

Many other things are mildly acidic. Plant substrates, nutrient mediums, and even our skin are all mildly acidic. These have values somewhere between 5 and 6.5 on the pH scale.

Plants tend to need mildly acidic substances, so a pH value of 5.5 or occurs often in nature and plant experts consider that to be “neutral” for plants.

Understanding the Importance of Acidity

Knowing how acidity works with your plants is a key step towards making certain you have the right acidity in your soil or solution. Since acidity has a very big impact on the solubility and absorbability of a variety of different food impacts, it plays a huge part in the growing process.

Not only that, but the acidity of the soil has a large influence on the breakdown of organic substances, the overall structure of the soil, and the amount of micro life in the ground.

The pH level also has an influence on which heavy metals, food elements, pesticides, and any other microorganisms that are growing in that medium wind up flushed out of the ground.

Having a pH level that is too high or too low can be quite detrimental to your plants. That is why it is so important to get the pH level just right.

How Is the pH Determined?

The buffering capacity is one of the most important factors when it comes to determining the overall pH value of a substrate or a solution. The buffering capacity essentially means that there is a balance present that will continually restore itself.

This means that putting a drop of acid into a liter of regular tap water (which has a pH of 7) won’t have much of an impact on the overall acidity of the water.

But if you put that same drop of acid into a liter of demineralized water, the pH level of the water will fall at a substantial level. This is because the tap water has bicarbonate in it, while the demineralized water does not.

Bicarbonate is essential when it comes to buffering substances for pH values that are between 5.5 and 7.5 when it is water. It also binds itself to acid that is in a particular solution. This releases carbon dioxide up into the atmosphere.

This is the process of neutralizing the acid, and changes in the overall acidity will be minor so long as there is that bicarbonate present.

Should you see a pH with a value of 5.3, that indicates that all of the bicarbonate has been used up. It also means that the solution no longer has buffers to it. That makes this pH unstable to the point that it will change immediately if any acid is added to it.

That means that the amount of acid that is necessary to get a feeding solution to the right acidity can be determined by the amount of bicarbonate present. You can actually get the content level of your tap water from your water company in a measurement of milligrams per liter.

The composition and freshness of the substrate are big factors in the substrate’s acidity and its buffering capacity. The overall presence of calcium, organic material, and bicarbonate will determine the overall level of the pH.

For instance, clay always has calcium carbonate in it and has a high pH value. This makes it more difficult to change, as opposed to acidic substances like sandy soil and peat soil.

What you might not realize is that the acidity in the soil can be greatly influenced by the plant itself. Some roots will secrete alkaline or acidic substances.

This depends on the stage of development of the crop, the differences in root temperature, the food available, and the light intensity.

All of these factors mean that the plant’s pH can fluctuate constantly. Any of these factors can change in some way, which can make the soil too alkaline or too acidic if the other factors are not the way they need to be.

The goal is to keep the root environment at an acceptable limit as far as the pH level goes. Doing this will keep your plants growing healthy and strong.

Changing the Water to Keep the pH Balanced for Your Plants

There are a number of additives that can make the water you use on your plants more acidic or alkaline in nature and these can have an impact on the way that your plants grow. Generally speaking, plants will thrive with a pH level of 5.5 to 6.5.

Anything below that 5.5 means it is acidic, while anything above is alkaline. If the pH of the water that you are using is off somewhere, there are ways to fix the problem so that your plants can grow at an improved rate.

The first step is to add any fertilizers or nutrients that you want to use for your garden. If you are growing your plants hydroponically, it is good to wait for about an hour before moving on to the next step in the process. For those growing in soil, 24 hours will do.

The next step is to test the growing medium. You can do this by taking a pH test, using a test strip or an electronic test kit, and following the instructions that come with the test. This will ensure proper testing so that you get an accurate pH reading.

When you get the reading, take it and compare it to the ideal pH type for the specific plant that you are growing. This helps you to determine if you need to lower or raise the pH for that specific growing medium.

Once you have determined which way the pH level needs to go, the next step is to get a gallon jug and fill it with clean water. Depending on the type of substance you are using to make the pH adjustment, it might be a different water requirement.

Ultimately, be sure to read the instructions that come with the water-to-substance mix to ensure that you are getting the right mixture. It does not have to be 100% exact, but it has to be close to make certain that the pH level changes the way it should.

Once you have your water in place, you will need to add your substance. This can be wood ash, lime, or a specifically formulated solution that is required to raise the pH level. If you are looking to lower the pH, you will need phosphoric acid, sulfur, or a pH-lowering solution.

If the directions call for a solid material or materials to be added to a liquid solution, you need to give those materials time to soak in the water. Usually a few hours is enough to allow it to steep, making it ready for mixing.

After your concoction has been mixed together, it is time to water your plants with that solution. If you are growing in a solid like perlite or in soil, make sure to water the plants with the solution the same way that you would water your plants with regular water.

If you are growing your plants hydroponically, you will want to add your pH solution to your hydroponic solution.

After you have watered your plants, it will again be time to test the pH levels. This is to determine whether or not another treatment is necessary. For hydroponics, this means waiting about a half hour to test the pH again.

If you are growing in soil or another type of solid, you will have to wait 24 hours before testing the pH level of the soil again.

How to Know if the pH Is Too Low

There are several factors that can help you determine whether or not the pH level in your soil is too low. If you notice any of these symptoms, it could be that your soil is a substrate that is too acidic and can be harmful to your plants.

If you notice that most nutrients can be dissolved easily, that could be one sign. This causes an excess of aluminum, iron, and manganese. With excessive rinsing comes potassium, phosphorus, molybdenum, and magnesium deficiencies.

You may also notice that magnesium deficiency in colder substrates, too. If your soil seems like it is generally poor or inhibited, that is likely a sign that the soil is too acidic for the general health of your plants.

If the pH is too low, you will need to take the steps to raise it to an appropriate level using a kit or one of the household items listed previously.

How to Know if the pH Is Too High

Of course, having a pH level that is much too high can be just as dangerous for your plants, stifling their ability to grow properly. And like a pH level that is too low, there are signs that can indicate that your pH level is too high.

If the nutrients that you add have a difficult time dissolving, this can lead to iron, calcium, and phosphate compounds precipitating.

You may also see a reduced rate of absorption for things like phosphate, iron, and manganese in particular. But that reduced rate of absorption can also be true for boron, copper, and zinc.

Ultimately, this difficulty dissolving and reduced absorption will lead to deficiencies. You will see this especially in colder, wetter growing mediums. When using sandy soils, the breakdown of substances will increase at a considerable rate if the pH is too high.

If you need to bring your pH level down, use your pH kit to bring it down, or you can try the household items listed above. Just like if the soil is too acidic, if it is too alkaline, plants will struggle to grow properly.

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