Adjusting Soil pH

[ontheline]

Good morning everybody,
I'm thinking I want to, it's time to, transplant into 3 gal. pots using FF Ocean Floor that is reading 6.8 ph. and I want to grow in 6.2-6.3 soil. I have 6 autos going, all planted on 4-1 in organic jungle growth from Lowes with 6.8 ph and all currently have 2 sets of leaves @ 2 3/4"-3" high and 4 of the 6 plants have varying degrees of yellow leaves and the photo is the worst plant. I'm watering the last 10 days thanks to Emilya with ro/di water using General Hydroponics trio and cal/mag alternating between watering with cal mag mixed water and watering with all 4 and both have 5.9 ph.

The question I have is, am I correct in thinking that I have to use some sort of acid to lower the soil ph before transplanting and if so, what is the fastest and best way to lower the ph without using battery acid? Or will the soil ph slowly lower using the lower ph water?
Thanks

 

[HappyHazmat88]

Hey I wouldn't worry about that to much...just transplant them, water them and give no nutes for about two weeks....this will allow them to feed off soil for a bit and help prevent nute burn.....but regardless what you decide and who's advice you follow... keep it simple. And good luck

 

[ontheline]

Thank you, and just to clarify when you recommend no nutes does that include no cal and mag in ro/di water?

 

[HappyHazmat88]

For cal-mag *I ONLY ADD IT IF I NEED IT* others here add every watering... So that would be your call if they need it or not....but they are still young and will be going into fresh soil they should have everything they need to start from soil....so imo I wouldn't add anything yet.

And just an added bit of info I am growing autos in both happy frog and ocean forest soil....so I am familiar and not just blowing smoke

 

[SmokingWings]

Thank you, and just to clarify when you recommend no nutes does that include no cal and mag in ro/di water?

The plants should not need to have any additional nutrients for the first 2 weeks in the soil you have mentioned. After that break-in period the grower has to start making decisions on what nutrients have to be added.

As HappyHazmat88 mentions in the quote below the plants will have everything they need for the first several weeks. Let the plant use that time to start growing the feeder roots, etc.

For cal-mag *I ONLY ADD IT IF I NEED IT* others here add every watering... So that would be your call if they need it or not....but they are still young and will be going into fresh soil they should have everything they need to start from soil....so imo I wouldn't add anything yet.

 

[Emilya Green]

Soil is set to the high end of the pH range recommended for soil, for a good reason. It is possible to apply acid to dissolve all the dolomite lime that has been purposely added to your soil to provide that top end buffer, and you soil will then be at a lower pH, but why? Why disable soils ability to provide upward drift?

As far as nutes go, why wait? I start fertilizing my plants on week 1. I am not into just feeding my plants the bare minimum they need to keep going.

 

[ontheline]

For cal-mag *I ONLY ADD IT IF I NEED IT* others here add every watering... So that would be your call if they need it or not....but they are still young and will be going into fresh soil they should have everything they need to start from soil....so imo I wouldn't add anything yet.

And just an added bit of info I am growing autos in both happy frog and ocean forest soil....so I am familiar and not just blowing smoke

Thanks and in my short time here everyone has been helpful and I've learned much just reading and to date my belief is the only smoke being blown in my direction is during exhale.

 

[ontheline]

Soil is set to the high end of the pH range recommended for soil, for a good reason. It is possible to apply acid to dissolve all the dolomite lime that has been purposely added to your soil to provide that top end buffer, and you soil will then be at a lower pH, but why? Why disable soils ability to provide upward drift?

As far as nutes go, why wait? I start fertilizing my plants on week 1. I am not into just feeding my plants the bare minimum they need to keep going.

Hey Emilya,
My thinking has been if I want to grow in 6.2-6.3ph range I reasoned why wouldn't it be easier to start with both soil and water where I want the ph to be rather than lowering the ph as I go and it just kind of made sense to me. As for the nutes, I have already been thinking of using them from the beginning with 2 different mixtures, 1 with ro water and ccal/mag and the 2nd with all 4 mixed and alternate days though I haven't decided on the dosage of the micro, bloom and grow nutes though I do have several days to decide, perhaps 1 tsp per gal. the 1st week until they settle in, perhaps full bore as you suggested to me previously.

 

[Emilya Green]

Proper pH is not given as one number... it is given as a range. You should want to grow in the 6.2-6.8 pH range... why limit it to such a narrow window as inert soil would provide you? Its not at all hard to go for the entire range and it doesnt require all the thought and energy you are putting into this, trying to adjust the soil to one specific narrow point. When you saturate the soil with a liquid, such as when watering to runoff, because the molecular weight of the water is so very much more than that of the soil, the pH of the liquid takes over. If you water at 6.3, the soil has no choice but to achieve 6.3 also. But soil is designed to drift, and as soon as that water hits the soil it starts to react with the dolomite and slowly starts to edge upward. Also as nutes are used, the liquid mix in the soil becomes less acidic. As a soil region dries, that region has no choice but to revert to the base pH of the soil, usually around 6.8pH. This allows your nutes to not only stay in the range the whole time they are working, but it allows your nutes to see all of the pH variances between 6.3 an 6.8, picking up each nute in turn where it is most mobile within the soil.

Let's say you adjust your soil to being a flat unwavering 6.3 pH. It is an error to think that you can just come along and then water with nutes, typically with a pH down in the 4's after adding to water, and simply apply it to your adjusted soil expecting everything to work. The problem is that again, the low pH water/nutes would take over and for a while your soil and everything in it will be a slave to that acidic water. The point is, even after taking pains to adjust your soil, you are still going to have to pH adjust your fluids. No matter what, you need to adjust your fluids before applying them to the soil. How then are you gaining any ground at all by killing the drift rate of your soil? It seems like unnecessary and extra work to me.

As far as the dosage of your nutes... every nute program has a chart, that starts off with lower dosages for smaller plants, and then ramping up to full nutes toward the middle of bloom. Follow the instructions. They already thought all of this out for you.

 

[ontheline]

Proper pH is not given as one number... it is given as a range. You should want to grow in the 6.2-6.8 pH range... why limit it to such a narrow window as inert soil would provide you? Its not at all hard to go for the entire range and it doesnt require all the thought and energy you are putting into this, trying to adjust the soil to one specific narrow point. When you saturate the soil with a liquid, such as when watering to runoff, because the molecular weight of the water is so very much more than that of the soil, the pH of the liquid takes over. If you water at 6.3, the soil has no choice but to achieve 6.3 also. But soil is designed to drift, and as soon as that water hits the soil it starts to react with the dolomite and slowly starts to edge upward. Also as nutes are used, the liquid mix in the soil becomes less acidic. As a soil region dries, that region has no choice but to revert to the base pH of the soil, usually around 6.8pH. This allows your nutes to not only stay in the range the whole time they are working, but it allows your nutes to see all of the pH variances between 6.3 an 6.8, picking up each nute in turn where it is most mobile within the soil.

Let's say you adjust your soil to being a flat unwavering 6.3 pH. It is an error to think that you can just come along and then water with nutes, typically with a pH down in the 4's after adding to water, and simply apply it to your adjusted soil expecting everything to work. The problem is that again, the low pH water/nutes would take over and for a while your soil and everything in it will be a slave to that acidic water. The point is, even after taking pains to adjust your soil, you are still going to have to pH adjust your fluids. No matter what, you need to adjust your fluids before applying them to the soil. How then are you gaining any ground at all by killing the drift rate of your soil? It seems like unnecessary and extra work to me.

As far as the dosage of your nutes... every nute program has a chart, that starts off with lower dosages for smaller plants, and then ramping up to full nutes toward the middle of bloom. Follow the instructions. They already thought all of this out for you.

I can pretty much tell you how I got to 6.2-6.3 thinking and it came mostly from reading a lot of post on this forum once I found it. Prior to that I read articles that like you said gave a variety ph ranges and usually stated 6.5 seems to be the ideal and I thought work towards 6.5-6.8 but try to achieve 6.5. Once I focused my reading here I came across several post where 6.2-6.3 was mentioned along with people saying if you do you'll probably be surprised and happy with the results or something along those lines so I adjusted my ph goal to 6.2-6.3.

As for the nutes, the 1st 7-9 days I used ro/di water and it wasn't until you responded to my 1st post here recommending GH products and when I looked into them I became aware ro water needs cal/mag added which I ordered along with the micro, grow and bloom trio because I liked what I read. I received the cal-mag the next day, mixed it according to the guide and started using it immediately. Once the trio arrived 2 days later I mixed them for seedlings along with adding cal-mag and began using both alternating between the 2 mixes with both at a 5.9 ph. All that being said, I knew I wouldn't transplant the seedling for at least 3 weeks which will be this weekend. When I checked the plants yesterday morning I saw where 2 plants had 1 leaf each that turned yellow while 2 plants had yellow spots on the tips of 2 leaves and when reading about a variety of causes the 1 that stuck in my head was root bound and the only way I can check the roots is to life them out of the pots I'm using so I thought instead of disturbing them I'll replant.

That being said, I checked the soil's ph new soil for the 1st time and it's at 6.8 ph. So I started thinking, I have 6.8 soil and 5.9 water how long and how much water will it take to lower the ph and what if I over do it and lower the ph to fast or to low and that's when I figured why not start with where I want to be. Now, I knew the soil had nutes in it but it never occurred to me they would be released by adding water until today. And that my friend was my entire thought process yesterday.

Lastly, as for using nutes from the beginning. after sharing your grow like a boss motto with me I've planned on using the current mixture for seedlings for about a week after transplant then switching to the recommended dose for general purpose before going to the aggressive growth mixture while alternating watering with the cal-mag-ro/di water mixture providing all goes well. And, if I may leave you with 1 final question for now? I know there is a specific order to mix the GH products but I have seen 2 different instructions as to the order to add the cal-mag, i says to add 1st, the other says to add it last which is what GH states if I'm remembering correctly and the order I used, cal-mag last, and I'd like to know what order you're using? Thanks again Emilya.

 

[Emilya Green]

I can pretty much tell you how I got to 6.2-6.3 thinking and it came mostly from reading a lot of post on this forum once I found it. Prior to that I read articles that like you said gave a variety ph ranges and usually stated 6.5 seems to be the ideal and I thought work towards 6.5-6.8 but try to achieve 6.5. Once I focused my reading here I came across several post where 6.2-6.3 was mentioned along with people saying if you do you'll probably be surprised and happy with the results or something along those lines so I adjusted my ph goal to 6.2-6.3.

As for the nutes, the 1st 7-9 days I used ro/di water and it wasn't until you responded to my 1st post here recommending GH products and when I looked into them I became aware ro water needs cal/mag added which I ordered along with the micro, grow and bloom trio because I liked what I read. I received the cal-mag the next day, mixed it according to the guide and started using it immediately. Once the trio arrived 2 days later I mixed them for seedlings along with adding cal-mag and began using both alternating between the 2 mixes with both at a 5.9 ph. All that being said, I knew I wouldn't transplant the seedling for at least 3 weeks which will be this weekend. When I checked the plants yesterday morning I saw where 2 plants had 1 leaf each that turned yellow while 2 plants had yellow spots on the tips of 2 leaves and when reading about a variety of causes the 1 that stuck in my head was root bound and the only way I can check the roots is to life them out of the pots I'm using so I thought instead of disturbing them I'll replant.

That being said, I checked the soil's ph new soil for the 1st time and it's at 6.8 ph. So I started thinking, I have 6.8 soil and 5.9 water how long and how much water will it take to lower the ph and what if I over do it and lower the ph to fast or to low and that's when I figured why not start with where I want to be. Now, I knew the soil had nutes in it but it never occurred to me they would be released by adding water until today. And that my friend was my entire thought process yesterday.

Lastly, as for using nutes from the beginning. after sharing your grow like a boss motto with me I've planned on using the current mixture for seedlings for about a week after transplant then switching to the recommended dose for general purpose before going to the aggressive growth mixture while alternating watering with the cal-mag-ro/di water mixture providing all goes well. And, if I may leave you with 1 final question for now? I know there is a specific order to mix the GH products but I have seen 2 different instructions as to the order to add the cal-mag, i says to add 1st, the other says to add it last which is what GH states if I'm remembering correctly and the order I used, cal-mag last, and I'd like to know what order you're using? Thanks again Emilya.

I rarely have a need to use calmag, but there is a very good reason to mix it into the water first, before anything else. Magnesium is one of the most reactive metals we know of and will react with many things that are included in our nutes and with each compound that it mixes with, it makes a different metal compound. If you mix in the nutes first and your magnesium mixes with the sulfur, you get magnesium sulfide. Mix with the calcium, you get magnesium calcite, etc etc... and none of them are as readily available to the plants than is magnesium oxide, which you get by mixing the magnesium first with just plain water. The reaction is immediate and then you don't have to worry about the magnesium, it will be in there in a stable form that is available to the plants. This is basic chemistry, or I wouldn't know it because this branch of science is way out of my studied fields. It is sort of frightening that GH didn't know that and that unfortunately tells me a lot about the company.
Regarding your yellow leaves... first, I think you are reporting that you are alternating 2 kinds of nutes and never giving plain pH adjusted water in between. That is a mistake... you are giving way too many nutes this way. Also, you are still in the mindset that you need to adjust your soil's pH, and you are thinking that you can do this by mis-adjusting the pH of your fluids to values way down low in the 5s. All you are doing is making your nutes unavailable to the plant until the pH eventually drifts into the proper range, and depending on how fast your plants are using the water, this might never happen. A lot of your nutes are being wasted and it doesn't surprise me much that you are seeing yellowing leaves. You are overthinking this, and making it harder than it needs to be.
Settle on one set of nutes, and use them in a feed/water/feed/water rotation. Always adjust to 6.3 pH and forget about trying to adjust the pH of your soil. First it is not necessary and second, you are shooting yourself in the foot as far as nutes go by trying this during an active grow.

 

[ontheline]

I did abandon my ph soil thinking after reading your comments along with HH's and SW's yesterday. As for the nutes, you are correct if I understand what you're advising. I began watering on 4-1 with ro water adjusted to 6.5 using baking soda until 4-14 I started using 5.5 ph ro water with cal-mag and on 4-17 I began using ro 5.5 water with cal-mag and the GH trio mixed and did not raise the ph. Yesterday after reading your comments I did a mini flush with ro water at 6.5 and I'm in the process of prepping 1 mix of ro to 6.3 as you recommend and 1 mix of ro with the 4 GH nutes to 6.3ph.

I confess I can be quite literal due to my previous hobby of growing hard corals in salt water where the parameters aren't very forgiving once established and for over thinking, I do, that's how I end up amusing myself.

Thanks again Emilya

 

[Emilya Green]

I did abandon my ph soil thinking after reading your comments along with HH's and SW's yesterday. As for the nutes, you are correct if I understand what you're advising. I began watering on 4-1 with ro water adjusted to 6.5 using baking soda until 4-14 I started using 5.5 ph ro water with cal-mag and on 4-17 I began using ro 5.5 water with cal-mag and the GH trio mixed and did not raise the ph. Yesterday after reading your comments I did a mini flush with ro water at 6.5 and I'm in the process of prepping 1 mix of ro to 6.3 as you recommend and 1 mix of ro with the 4 GH nutes to 6.3ph.

I confess I can be quite literal due to my previous hobby of growing hard corals in salt water where the parameters aren't very forgiving once established and for over thinking, I do, that's how I end up amusing myself.

Thanks again Emilya

I too maintain a saltwater reef tank, so I understand your desire to be accurate. Remember that in the reef tank business we are into micro adjustments and this is why vinegar and baking soda work so well for that application, but plants and soil need a little more oomph than they can provide.
I am very pleased to hear that you are responding to my explanations and now understanding soil a little better. It sounds like you are pre-mixing nutes for later use, and I want to warn you to be very careful with that because things can settle out and overnight the pH can change quite a bit. Remember that as soon as you get the nutes out of the bottle and into the pH range where they break free of their chelation, they are then active and able to interact against each other. For the same reasons that chlation is being used to get the stuff in the bottle and to you, you should not let your nutes sit ready to go for very long.
As I mentioned above, baking soda is not the best pH adjuster and your pH will start to rapidly change over time. My pH adjusters of choice are these: For pH up I use pickling lime from the grocery store. This very powerful pH up has to be stored in glass containers because it will eat plastic, but a very weak dilution of this stuff provides a long lasting pH adjustment, and it is super cheap to use. For pH down, I like sulphuric acid, easily and cheaply attained by going to the car parts store and getting some battery acid, a box will set you back less than $10. Then get a gallon jug of distilled water and remove one cup of water. Carefully add back 1 cup of the battery acid, shake well, and this 15:1 dilution is safe and works almost exactly like the commercial pH down product that is 200x more expensive.

 

[Fuzzy Duck]

I don't know why peeps over think this PH thing for growing in soil ?

PH 6.8 is mildly acidic which quite a lot plants over the entire world are very happy to grow in those conditions including cannabis !

Which I've used a soil/compost blend of same PH value for over 10 years with out issues.


I must admit I am not a person who adjusts nutrient enriched water PH for soil growing either, no matter whether it is organic or synthetic salt based as in modern horticultural principles this simply is not done but a rather bizarre concept in the cannabis growing community.

When nutrients are available over a range of PH of the soil & when not such as FE or iron this come in a chelated form so plants can use it.

soil_ph_nutrient_availability

• Fuzzy Duck
• Jan 28, 2014

 

[SmokingWings]

I don't know why peeps over think this PH thing for growing in soil ?

My theory is that pH is so important to successful growing of anything in a hydro method that new growers felt it had to be the same for their preferred mix. Farmers need the know the average pH of their farm but they do not seem to care about getting a reading of the soil around the roots of every plant on their 1/4 section. Then there are the urban gardeners who get a soil test so they can know the NPK recommendations for their backyard and the pH number is almost always included in the results.

Everywhere we go we seem to see that pesky pH number so we get the feeling that it is the most important thing out there. Some of us end up feeling that it is a number that has to be thought about every minute from the time the seed hits the dirt to the time the scissors hit the few remaining yellow leaves at the end.

And that is what starts so many along the road to over thinking the pH of the soil.

 

[ontheline]

I too maintain a saltwater reef tank, so I understand your desire to be accurate. Remember that in the reef tank business we are into micro adjustments and this is why vinegar and baking soda work so well for that application, but plants and soil need a little more oomph than they can provide.
I am very pleased to hear that you are responding to my explanations and now understanding soil a little better. It sounds like you are pre-mixing nutes for later use, and I want to warn you to be very careful with that because things can settle out and overnight the pH can change quite a bit. Remember that as soon as you get the nutes out of the bottle and into the pH range where they break free of their chelation, they are then active and able to interact against each other. For the same reasons that chlation is being used to get the stuff in the bottle and to you, you should not let your nutes sit ready to go for very long.
As I mentioned above, baking soda is not the best pH adjuster and your pH will start to rapidly change over time. My pH adjusters of choice are these: For pH up I use pickling lime from the grocery store. This very powerful pH up has to be stored in glass containers because it will eat plastic, but a very weak dilution of this stuff provides a long lasting pH adjustment, and it is super cheap to use. For pH down, I like sulphuric acid, easily and cheaply attained by going to the car parts store and getting some battery acid, a box will set you back less than $10. Then get a gallon jug of distilled water and remove one cup of water. Carefully add back 1 cup of the battery acid, shake well, and this 15:1 dilution is safe and works almost exactly like the commercial pH down product that is 200x more expensive.

A reef keeper as well, so you have some understanding of my fixation or test readings not to mention that's an expensive time consuming hobby and you might hate to hear how I got out. I had a 90 gal. up and running for about 7 yrs. mostly acro's some monti's and 1 5-6" blue elflo which was my favorite, all grown from frags. I had to run some errands one day and was gone for about 6 hrs. and returned home and every coral had rtn'd. After my temper tantrum I was done though I kept the tank running for several weeks. When I started tearing it down I saw some spots high on a wall behind the tank and discovered it was oil I believe was slung out from a ceiling fan and surmised oil hit the water and wiped it out. Either way, I didn't have it in me to start over.

As for the ph, prior to your guidance I was looking at the soil ph in the same way I looked at the water ph and now it's making more sense. I did start to adjust the water ph with baking soda though after reading your latest I have time to get pickling lime for sure as my ro water is 5.5 and after flushing yesterday I don't think I'll need to water until perhaps tomorrow and that'll give me some time to read more on the acid. My transplant will be into 3 gal. pots and I'm thinking to start I'll mix a gallon at a time until I see what the actual need will be. Until my next hair brain idea Emilya, I thank you for your guidance.

 

[Fuzzy Duck]

My theory is that pH is so important to successful growing of anything in a hydro method that new growers felt it had to be the same for their preferred mix. Farmers need the know the average pH of their farm but they do not seem to care about getting a reading of the soil around the roots of every plant on their 1/4 section. Then there are the urban gardeners who get a soil test so they can know the NPK recommendations for their backyard and the pH number is almost always included in the results.

Everywhere we go we seem to see that pesky pH number so we get the feeling that it is the most important thing out there. Some of us end up feeling that it is a number that has to be thought about every minute from the time the seed hits the dirt to the time the scissors hit the few remaining yellow leaves at the end.

And that is what starts so many along the road to over thinking the pH of the soil.

In a way you are correct with concerns of hydro & inert growing mediums where the PH of nutrient solution is the main objective as the growing medium may not have a natural PH value if any at all !

As for soil then PH to some degree helps in optimal growing conditions this is why pre mixed composts/soil are normally around PH 6.8 to a few points below as it is very hard to get an industry standard across the world in my own experience.

Interesting mention about farms, I've used that in the past !

I spent a few months working for a firm taking soil samples of farm land grid reference, GPS coordinates this was mostly PH related as different bed rocks or soil types base PH value would effect top soil PH value (root zone) which in return could effect yield & the rest of it.

Technical speaking the firm advised farms how to amended their PH value of the farms soil to more ideal conditions depending on conditions which was mildly complicated & no I did not do the soil science bit either or correct ratios to amended such farms soil.... some one else got paid more than I, for that


Ye I get new grower sizzle I was one of those a long time ago !

Forums decades of misconceptions keeps forums going don't forget to do some real gardening research as well not related to cannabis you might learn some thing

 

[SmokingWings]

Forums decades of misconceptions keeps forums going don't forget to do some real gardening research as well not related to cannabis you might learn some thing

Yes.

Growers, gardeners or whatever we want to call ourselves, who feel that avoiding basic research is a shortcut usually end up with basic level plants.

 

[SmokingWings]

As for soil then PH to some degree helps in optimal growing conditions this is why pre mixed composts/soil are normally around PH 6.8 to a few points below as it is very hard to get an industry standard across the world in my own experience.

And that hits the nail on the head to use a famous saying.

We spend good money buying pre-mixed soils. Or, we spend good money on the ingredients and then spend our time mixing up our own batches of soil. If it is the wrong pH then why or how did those companies get the reputation for producing a soil that we should buy? Or why are there soil recipes that have been recommended year after year if the end result is a sub-par soil with the wrong pH?

Measure or check the pH of the water that will be used. Adjust the water pH if need. Be happy.

(Hydro is different. Measure the water in and out. Know the numbers. Life goes on.)

 

[Fuzzy Duck]

Yes.

Growers, gardeners or whatever we want to call ourselves, who feel that avoiding basic research is a shortcut usually end up with basic level plants.

Aye their is a broader opinion & you may need to have a interest in other circles related to any points of focus one must endeavour to achieve !