Many of my viewers ask a very important question – what is the correct soil ph for plants and how do I test this and how do I change it? The answer to this question is not so simple, but I shall try to make it simple and tell you what is the perfect or the ideal Soil PH for most plants and also few natural ways to soil amendment that can make your soil PH to the desired level.
Sunlight, water, nutrients—these are the basic factors for plants to thrive. But there is another crucial factor that determines whether your plants thrive or struggle to grow? It’s a soil property called ph. An ideal range of soil PH is indispensable for proper nutrient absorption by the roots.
What is PH? PH is a just a number or a value ranging from 0 to 14. 7 – that’s the middle of the scale is considered Neutral PH and anything below 7 is called Acidic or Sour in layman’s term and Anything above 7 is called Alkaline or Sweet.
So, what is the Perfect or the Ideal or the desired Soil PH for most plants? How will I measure this and How will I adjust the soil ph to this desired level?
This Value of Ideal soil pH could make a huge difference and really an important step for those looking to grow bountiful gardens. Because most of the nutrient absorption at root level happens at this ideal ph level. You may be adding a lot of fertilizers, supplements like micronutrient powders and stuff like that regularly to your plant, but if it’s not producing good results and you still have anaemic plants, then you should suspect something wrong with the soil PH, either it’s not favourable to your plant or the plant is unable to adapt to the ph changes.
For most plants, the ideal ph has to be SLIGHTLY ACIDIC, like around 6.5. but this doesn’t mean that plants cannot grow outside this range. Places with lots of vegetation and rain, such as forests, tend to produce acidic soils whereas Dry and arid zones like deserts are more likely to be alkaline. We will learn about acid loving plants and alkaline soil preferring plants later in this episode.
How do I test Soil PH at home?
Let me demonstrate 3 easy ways to test your soil PH at home. This soil testing is actually fun and you can share this with your kids to teach them simple science or chemistry.
The First Method is using Litmus Paper. This is simple school chemistry. And this is not expensive. You can buy this simple litmus paper kit at any stationary store or even online. This is just litmus paper with color chart showing a PH value for each color that matches with your test result. PH of 7 is Neutral, PH below 7 is acidic and above 7 is alkaline. The most important thing is to use distilled water for all these tests you conduct, because the PH of distilled water is neutral.
So, How to Test Soil Using Litmus Paper Method?
Collect one tablespoon of soil from your garden either from container or from ground. You can take the soil from a little deeper like 2 inches below the soil.
- Add equal amount of distilled water – that’s 1:1 ratio. We are taking distilled water because it has neutral PH of 7. You can also take water from your water purifier, test it with litmus paper first.
- So, for 1 table spoon of soil you would add 1 tablespoon of water.
- Now nicely mix this by Stirring for few seconds.
- Let it sit for 10 minutes.
- Start stirring the sample again and now dip the litmus paper to take your measurement. Wait for few minutes for color change and then match it with the color coding chart that came along with your litmus paper kit.
Purchase Litmus Paper kit: https://amzn.to/3jKY4ec
The Second Method is a rough and easy DIY method you can try at home to know whether your soil is acidic or alkaline.
- Take a small amount of soil from your garden or container in a small glass.
- Now Pour some vinegar to this soil sample. If it fizzes and bubbles you have an alkaline soil because the alkaline content in soil reacts with acid like vinegar which is chemically acetic acid.
- Take another soil sample from your garden. Here for demonstration purpose, I know that this is an acidic soil. Now Add baking soda one or two teaspoons and mix it with soil.
- Then wet the soil baking soda mix with distilled water. If it fizzes and bubbles your soil is acidic, because the acidic content in soil reacts with a base or alkaline stuff like baking soda. That’s it!
The Third Method is using Soil PH Testers – There are two types of soil ph meters. Manual type or digital soil PH testers. Which one of these to choose? And These are easy to use portable gadgets with probes to insert into the soil. These give instant readings. These manual type of probe testers are not so reliable but they are inexpensive and handy. But These digital testers are more accurate but little expensive. These are actually 3 in one or 4 in one meters which also test Temperature, Light and Moisture along with PH. These factors are also important for gardening. We will discuss in detail about these meters in some other episode and how to make use of these for max benefit in gardening.
PURCHASE LINKS:
Manual Ph meter:
Digital Ph Tester:
How do I adjust my soil PH if its too Alkaline or even neutral to achieve the ideal PH around 6.5.
- Rain Water: If it’s a rainy season and if soil is neutral or alkaline, you don’t have to do anything. Just check the soil PH after rains. Rain makes the soil acidic naturally.
- Adding Compost to your soil: This is the basic requirement. At least 20 to 30 percent of your soil or potting mix should have a well decomposed manure like cowdung or horse dung or leaf compost or even vermicompost. If you add compost to your soil now, you need to wait for at least a month or two to see the ph change effect because this is a gradual process.
- Vinegar: White Vinegar about 1 or 2 teaspoons per litre or water can be used to lower the soil ph drop. Watering with this solution thoroughly once a month or even once in 15 days will help.
- Coffee ground or even Tea waste: The tannic acid present in this will lower the ph of your soil slightly. You can even add used tea or coffee waste to your plants to lower ph.
- Lemon Juice: Some even recommend adding 1 -2 teaspoons of lemon juice per liter of water and watering with this solution once in a month.
- Shredded Pine barks or any evergreen barks if available can be used to mulch on the top soil to make your soil acidic.
- Sphagnum Peat Moss is another remedy to lower soil ph.
- Alum : chemically called Potassium Aluminum Sulfate is a compound commonly used in water purification. This is available in powder or in crystal form. You can powder the crystals and use about 5 – 10 gms per liter of water and water your plants monthly once. You can watch a detailed episode on Alum and its uses in Gardening from a link in description below.
- Chemical or commercial products containing elemental sulfur can also be used to lower soil ph.
- And Lastly, If your soil is too acidic and you may want to raise the soil ph a bit higher, then you can use wood ash as a natural remedy for this job. Wood ash is a cheap remedy to make your soil alkaline.
Purchase Links: Alum: https://amzn.to/3JNvHGN
Wood Ash: https://amzn.to/3JNjPV6
Alum or Potash Alum is a hydrated double salt available in crystal form or in powdered form or even in liquid form. This can be white alum or red alum, but the compound is the same. It’s chemical name is Potassium Aluminium Sulphate. This compound is eco-friendly and has no hazardous effects on plant, animal, or human ecosystems. It is easily available at any grocery stores or supermarkets and even in some garden stores. This is also available in various shapes like these blocks. These are actually meant to use as an after shave disinfectant.
Food-grade alum is approved by the FDA for household use and also medical use. But how is alum useful in gardening and what are the benefits of Alum in garden or on plants? Let’s list out these five best uses of alum for plants one by one.
5. ALUM PESTICIDE: Alum acts on pests by two modes: one by infiltrating into the body surface of the pest and second by ingestion by the pest. Alum pesticide in 10 to 20% concentration is found to be very effective on many pests including aphids, whiteflies and mealy bugs which are the most common pests in our gardens. It’s also effective in vegetable gardening to kill cabbage worms, cut worms, and other bugs. This pesticide can be used as an alternative to neem oil. Neem oil is not available in many parts of the world.
How to make Alum pesticide?
We will show you the recipe for 1 litre of water in 3 quick and simple steps.
Step 1: Take 100 to 200 grams of alum. For home gardening you can use 100 gms of alum but to kill larger pests like cabbage worms or cutworms, you can take 200 gms.
Crush the larger crystals into smaller ones or use Alum Powder.
Step 2: Take 1 litre of clean water in a spray can or any container and add 100 to 200 gms of alum as discussed, depending on the pest type and intensity.
Step 3: Now add a surfactant like liquid soap or glycerine like about 5 to 10 ml.
You can now load into your spray bottle, Shake it well and spray it on the affected plants. Make sure you do a patch test on a leaf first to test the potency, before spraying on the entire plant.
4. TO REPEL INSECTS: Alum keep slugs and snails away and also certain other insects like cockroaches. Just sprinkle some alum powder or coarse crystalline powder over the affected areas.
3. MOSQUITO CONTROL: It’s an effective larvicide and kills mosquito larvae in stagnant waters in your home and garden. Just sprinkle alum powder over these stagnant waters and you are done.
2. SOIL AMMENDMENT: The first thing you must know is “Alum is NOT a fertilizer”. First and foremost use of alum in garden is to alter the soil PH.
For beginners: Soil PH plays a very important in plant growth and a balanced soil PH is really important for absorption of nutrients by the roots. A pH level of 7.0 is neutral, a pH below 7.0 is acidic, and a pH above 7.0 is alkaline. Also People living in Dry climates often have an alkaline soil, while climates with higher rainfall typically have acidic soil. Generally, most plants do well with soil pH between 6.0 and 6.5 – i.e, a slightly acidic PH. However, there are some plants which love a more acidic soil like hydrangeas, grapes, strawberries, blueberries, and even our rose and hibiscus trees. These are called acid loving plants.
But, before adding alum to soil, you first need to check your soil PH. A simple PH testing tool like this is really useful. You can also purchase a digital soil PH testing tool like this. If you do not have soil PH meter, you can roughly test your soil PH – like whether alkaline or acidic, using baking soda and vinegar hack. You need to add alum only if your soil is alkaline.
If you soil is alkaline or neutral you need to add 1 teaspoon of alum powder per litre of water or 1 tablespoon of alum per gallon of water. Mix it well and then water this to your plant thoroughly and check soil PH after 10 to 15 days. Repeat again if necessary.
1. INCREASE FLOWERING: Sometimes, your plant may not be flowering at all, even with proper sunlight, watering and fertilizing. The fault may lie in improper soil PH. Like acid loving plants including rose and hibiscus need a soil PH of 5.5 to 6.0 for proper absorption of nutrients. In such cases, you need to alter the soil PH as discussed in point number 4. This will certainly boost flowering in these plants.
Let’s begin with a simple explanation. I assume that most of us know What is PH. And for people who want it more simplified, PH is a just a number or a value ranging from 0 to 14. 7 – that’s the middle of the scale is considered Neutral PH and anything below 7 is called Acidic or Sour in laymans terms and Anything above 7 is called Alkaline or Sweet.
Without going into too much depth, we will come straight to the point. What is the Perfect or the Ideal or the desired Soil PH for most plants. How will I measure this and How will I adjust the soil ph to this desired level.
This Value of Ideal soil pH could make a huge difference and really an important step for those looking to grow bountiful gardens. Because most of the nutrient absorption at root level happens at this ph. You may be adding a lot of fertilizers, supplements like micronutrient powders and stuff like that regularly to your plant, but if its not producing good results and you still have anaemic plants, then you should suspect something wrong with the soil PH, either its not favourable to your plant or the plant is unable to adapt to the ph changes.
For most plants, the ideal ph has to be SLIGHTLY ACIDIC, like 6.5 plus or minus 0.2. but this doesn’t mean that plants cannot grow outside this range. Places with lots of vegetation and rain, such as forests, tend to produce acidic soils whereas Dry and arid zones like deserts are more likely to be alkaline.
Well now, How do I test Soil PH at home gardening level? Every hobby gardener must have this handy ph testing tool. This is not at all costly. Actually there are a wide range of soil ph meters including digital meters with varying costs. This one is actually inexpensive and does the job for me. You can purchase this from HERE.
Now, How do I adjust my soil PH if its too Alkaline or even neutral to achieve the ideal PH around 6.5. or a better question is How to make soil more acidic specially for acid loving plants. You can checkout my video on the list of acid loving plants.
Here are the top 10 natural ways to make your soil acidic if its alkaline and vice versa.
- First and foremost is the Rain Water: If it’s a rainy season and if soil is neutral or alkaline, you need not do any thing. Just check the soil PH after rains. Rain makes the soil acidic naturally.
- Good Compost in your soil: This is the basic requirement. Atleast 20 to 30 percent of your soil or potting mix should have a well decomposed manure like cowdung or horse dung or leaf compost or vermicompost. This itself is actually sufficient to make your soil have that desired perfect PH value. If you add compost to your soil now, you need to wait for atleast a month or two to see the ph change effect because this is a gradual process.
- Vinegar: White Vinegar about 1 teaspoon per liter or water can be used to make the soil ph drop, like watering with this solution thoroughly once a month or so. Its always better to check the soil ph before and after application.
- Coffee ground or even Tea waste: The tannic acid present in this will lower the ph of your soil slightly. You can watch a separate video on this topic HERE.
- Lemon Juice: Some even recommend adding 1 -2 teaspoons of lemon juice per liter of water and watering with this solution once in a month.
- Shredded Pine barks or any evergreen barks if available can be used to mulch on the top soil to make your soil acidic.
- Sphagnum Peat Moss is another remedy to lower soil ph. You can see my separate video on this topic HERE.
- Alum : chemically called Potassium Aluminum Sulfate is a compound commonly used in water purification. This is available in powder or in crystal form. You can powder the crystals and use about 5 – 10 gms per liter of water and water your plants monthly once. You can watch a separate video on Alum in Gardening for more details.
- Chemical or commercial products containing elemental sulfur can also be used to lower soil ph.
- If your soil is too acidic and you may want to raise the soil ph, then you can use wood ash as a natural remedy for this job. You can watch a detailed video on this topic HERE.