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GBK
23-12-11, 03:58 PM
Now for the 1st time in 3 years im about to start checking the PH of my waters and run off as well as my nutrient mix that are to go into the soil.I came across this on the Internet,So many people have copied and pasted it im not sure who is the original writer is,But its a simple guide that I myself was able to follow and lead me into doing the checks that are essential for optimum health growth.

Potential Hydrogen Ions or pH shows the type of the soil that you have or amount of lime or calcium that the soil has. As a general rule, soils in moist climates tend to be acidic while those in drier areas tend to be more alkaline. When the measure of the soil is below 7.0, then the soil is deemed as acidic, while if the pH measure of the soil is more than 7.0, then the soil is alkaline in nature. All plants give themselves to different degrees of soil acidity and some plants like Rhododendrons or Heathers are extremely sensitive to the acid nature of the soil. Therefore it’s important that the soil have the correct pH balance to help plants grow effectively. If you have a county extension office nearby you can take a soil sample and they will give you the results of your soil. You can then take appropriate action. Alternatively you can buy a soil pH test kit and have the results instantly. They also sell soil pH meters that will give readings of your soils current conditions. This type of pH tester usually runs on batteries.

It’s imperative to understand that soil is like a living organism. For healthy soil, it needs to be replenished on a continuous basis. If the soil is healthy, it gives natural protection to the plants that thrive on it as well as providing a security cover against the diseases, which may affect the plants.

How to measure the ph of your soil's runoff

How to test the pH of your soil mix

Measuring the pH of soil is just as important as with hydro applications, but few people know how to test soil pH to see if it is within the optimum range for growing robust healthy plants. Here I will try to explain my method of testing any soil / soil less mix, enabling me to spot any problems and correct them if necessary.

Firstly, wait till your soil has dried out and is due for its next watering schedule. Then take some plain water that you usually water your garden with, and adjust the pH to 7.0. You must make sure that you know the exact pH of the water going into your soil, and the neutral 7.0 is best, but anywhere from 6.5 – 7.0 will suffice.

Then place your pot into a bowl of some sort to catch the runoff water, and then start to water your soil slowly (with your pH- corrected plain water) till the water starts to drip from the bottom.
It’s the first drops of water that will give you the best reading of your soil, so make sure to water slowly till you see the first droplets. Then remove the pot from the bowl to eliminate excess water entering the bowl. Then perform the pH test on the runoff and compare it too your initial test.
The results of the runoff test will likely be lower than your starting value of 7.0. If this is the case, a small drop of 0.5 pH to 6.5 pH (example) would be ok and your soil needs no further alterations at the moment. But that’s not to say that it won’t need any future tests at all, just not at this time.

[Editor’s note: It may be beneficial to obtain an initial sample, as well as a ‘full flush’ sample in seperate bowls. In addition, test several plants in the garden just to verify your results]

What if the pH is off?
If your results prove to have dropped considerably, say to around 5.5 (which can happen in late stages of flowering), you will need to add some lime into your soil to help buffer the pH back up again.

Remove the first inch or so of soil, taking care not to damage any roots whilst performing this task. Then sprinkle the lime into the pot, nice and evenly at a rate of 1 teaspoon (5 ml) of lime per gallon of soil. Then replace the soil you removed earlier, and saturate the soil good to wash in the lime.

Do the same test next time your plants need watering just to check that everything is fine, if more lime needs to be added then just repeat the process again till you reach close to 6.5 – 7.0 with the runoff.

Ensuring that your pH is correct should be done throughout the life cycle; this will help eliminate any nutrient lockout that may occur. I recommend doing this once a month just to keep the PH in check, and you should never have a problem with deficiencies caused by pH lockout.

How can I raise or lower the pH of my soil mix?

Growing in soil and adjusting pH levels

A lot of gardeners have trouble with the pH of their soil. A high pH can lock out needed nutrients and mimic other problems like Fe and Mg deficiencies. The biggest mistake new growers make is to try and correct pH problems too quickly. The first step in determining if high pH is the real problem, is to pick up a good pH tester. Don't be afraid to shell out the cash for a good one, it's well worth it!

Here are some recommendations: (All sell for under $100.00)

1. Milwaukee makes two styles of hand-held pH meters. A small "pen" called the Sharp and the larger Smart Meter. Both are easy to use. The Sharp pens are splash-proof (although not totally waterproof), and have a large easy to read display. They also have a detachable, replaceable probe.

2. Oakton - Same type of pH tester as Milwaukee makes, but it's made a little better imho. These are totally waterproof. (It floats.)

3. Shindengen ISFET pH Meters are state-of-the-art pH pens and work with a totally different method of measurement. This pen uses a solid state Ion Sensitive Field Effect Transistor (ISFET) instead of the fragile glass electrodes used by traditional pH pens. They have replaceable tips that change from opaque to clear when they need to be changed.


What is pH, and what do the terms acidic and alkaline mean?
The acidity or alkalinity of the soil is measured by pH (potential Hydrogen ions). Basically it's a measure of the amount of lime (calcium) contained in your soil, and the type of soil that you have. A soil with a pH lower than 7.0 is an acidic soil and one with a pH higher than 7.0 is considered to be alkaline. A pH of 7.0 is neutral.


Adjusting your soil pH :
Once you have determined the pH of your soil with a good tester, you can amend the soil if needed to accommodate the plants in your garden using inexpensive materials commonly available at your local garden center.

Adjust soil pH slowly over several days time, and check pH often as you go. Radical changes in pH may cause osmotic shock damage to the roots.


Raising soil pH : (to make it more alkaline)
It is generally easier to make soil mixes more alkaline than it is to make them more acidic. The addition of dolomite lime, hardwood ash, bone meal, crushed marble, or crushed oyster shells will help to raise the soil pH.

by MisterIto
In soil: add dolomite limestone to the soil; use small amounts of hydrated lime.

Raising hydroponic pH : (to make it more alkaline)

In hydroponics: use potassium silicate, provides silicon at an effective doseage.
In bioponics/hydro-organics: add small amounts of sodium bicarbonate or lime.

Lowering soil pH : (to make it more acidic)
If your soil needs to be more acidic, sawdust, composted leaves, wood chips, cottonseed meal, leaf mold and especially peat moss, will lower the soil pH.

by MisterIto
bloodmeal/cottonseed meal during vegetative; bonemeal during flowering.

Lowering hydroponic pH : (to make it more acidic)

In hydroponics: use nitric acid during vegetative; phosphoric acid during flowering.

Contributed by: Spiritual.Fa
23-08-2003

Stabilizing pH with Dolomite lime

The best way to stable PH is by adding 1 ounce of Dolomite Lime per 1 gallon of planting soil.

Dolomite Lime is available in garden nurseries. Buy the fine Dolomite powder (There may be several kinds of Dolomite like Rough, Medium, Fine)

Dolomite Lime has been a useful PH stabilizer for years, since it has a neutral PH of 7 when added to your soil it stabilizes your soil at PH 7.

Mix the dry soil medium and dolomite together really well, give the mix a good watering then after the water has had chance to settle and leech into the soil a bit give the mix a really good stir. Then water the soil/lime mix and give it another stir

Best plan is to mix fine dolomite lime into your mix before planting. Fine Dolomite will help stabilize your pH; however, if the ph becomes unstable or changes, you can then use Hydrated Dolomite Lime. Add some of the hydrated lime to luke warm water and give it a good stir then water your plants with it. Give the plants a good watering with this hydrated lime added and your PH should fall or rise back to 7

Other Benefits of Dolomite Lime

Dolomite lime is also high in two secondary nutes that can often be overlooked by fertilizers; dolomite is high in both (Mg) Magnesium and (Ca) Calcium.

Soil Runoff pH, Flushing to correct lockouts- Why and how to do it!



This is a common question that comes up when troubleshooting, so I thought I'd post up a little summin summin.

Why do you want to know your runoff pH? Simple- it's an indication of how your water, fertilizer, and grow medium are interacting chemically.

There are 3 measurements that are important to know when you are caring for plants growing in a soil or soilless medium.
The first is the pH of your source water.
Next is the pH of your nutrient solution after the fertilizers and supplements are added.
Last is the pH of your soil. But that's the hard one! You can't just stick a pH meter in the dirt and get an accurate reading, and the cheap metal-probed meters that show this are usually not all that precise.

So how does one determine soil pH accurately? With a runoff test! First, measure the pH of your tap water and record it. As an example, let's say that it is 7.0, exactly neutral.

Now place the pot over a clean rinsed container and pour enough water through the soil to start dripping out the bottom. Collect about 4 ounces of runoff water. Check to see if it is discolored as well.

Now, if you only have liquid indicator, which is just fine, pour this water into a clean small tube or the test vial that came with your pH testing kit.Add a few drops of indicator solution, shake, and read the color change.
If you have a meter, simply stick the electrode in the water and read.

Let's say that your runoff comes out at 6.5. How did that happen? The water passed through a more acidic matrix and dropped its pH. You can assume that your true soil pH is a couple tenths of a pH point lower than the runoff in this case- I'd assume about a 6.2. If it comes out HIGHER, just go in the opposite direction. If it came out 7.5, you can assume that you need to drop down from about 7.8.

You want around 6.0-6.5 for a soilless mix, or 6.3-6.8 for soil.

Pics:
1- Propping up the plant over a container to catch runoff
2- POuring clean water through the soil
3- For liquid indicator, pour into clean vials
4- Check the pH against the color chart
5- Adjust the flush water if necessary

How to test the pH of your soil mix

Measuring the pH of soil is just as important as with hydro applications, but few people know how to test soil pH to see if it is within the optimum range for growing robust healthy plants. Here I will try to explain my method of testing any soil / soilless mix, enabling me to spot any problems and correct them if necessary.

Firstly, wait till your soil has dried out and is due for its next watering schedule. Then take some plain water that you usually water your garden with, and adjust the pH to 7.0. You must make sure that you know the exact pH of the water going into your soil, and the neutral 7.0 is best, but anywhere from 6.5 – 7.0 will suffice.

Then place your pot into a bowl of some sort to catch the runoff water, and then start to water your soil slowly (with your pH- corrected plain water) till the water starts to drip from the bottom.
It’s the first drops of water that will give you the best reading of your soil, so make sure to water slowly till you see the first droplets. Then remove the pot from the bowl to eliminate excess water entering the bowl. Then perform the pH test on the runoff and compare it too your initial test.
The results of the runoff test will likely be lower than your starting value of 7.0. If this is the case, a small drop of 0.5 pH to 6.5 pH (example) would be ok and your soil needs no further alterations at the moment. But that’s not to say that it won’t need any future tests at all, just not at this time.

[Editor’s note: It may be beneficial to obtain an initial sample, as well as a ‘full flush’ sample in seperate bowls. In addition, test several plants in the garden just to verify your results]

What if the pH is off?
If your results prove to have dropped considerably, say to around 5.5 (which can happen in late stages of flowering), you will need to add some lime into your soil to help buffer the pH back up again.

Remove the first inch or so of soil, taking care not to damage any roots whilst performing this task. Then sprinkle the lime into the pot, nice and evenly at a rate of 1 teaspoon (5 ml) of lime per gallon of soil. Then replace the soil you removed earlier, and saturate the soil good to wash in the lime.

Do the same test next time your plants need watering just to check that everything is fine, if more lime needs to be added then just repeat the process again till you reach close to 6.5 – 7.0 with the runoff.

Ensuring that your pH is correct should be done throughout the life cycle; this will help eliminate any nutrient lockout that may occur. I recommend doing this once a month just to keep the PH in check, and you should never have a problem with deficiencies caused by pH lockout.

darren1970
23-12-11, 06:00 PM
Excellent find Buddha,Makes so much sense,Many thanks

GBK
23-12-11, 06:09 PM
My thoughts exactly mate,As from today PH is my No1 priority unless i find out something far more important that needs careful attention,Cheers

wilbur
24-12-11, 11:14 AM
oh christ! this can be simplified so much more. hang around ... I 'll go and find the post

...https://www.thctalk.com/cannabis-forum/showthread.php?52504-CHANGING-POTTING-MIX-pH

wilbur
24-12-11, 11:16 AM
made a mistake , sorry dear reader

C.W.
30-12-11, 02:41 PM
just remember if you add lime to the soil to adjust it and the lime in it was still good you will possibly cause issues. if lime is still able to buffer it will rise on its own with just water as the more you pour in the medium. if it wont go back up and hold then its safe to add. when they make the new soil they dont just add any amount of lime to be in mid 6 to 7. its a calculation and adding more is messing with that and its cation exchanges ability.