Soil Ph Too Low! Help!

Hi everyone newbe here. Wanted to get opinions on how I can get my soil PH back up as fast as possible?

I bought 12 mother plants from a local farm. They are 3-4ft tall in 7gal pots with I think a pro mix medium. I’ve had them two weeks. I noticed I’m getting a lot of yellow leafs, at first I thought stress from the move or nitrogen deficiency. I give them a double dose of Bio Thrive but no luck.

The more I’ve been reading on here I got concerned that I was in nut lockout. So I tested my run off. 6.5 going in come out 5-5.5!
The run off was also a brown color which I read was not good. I have not preformed a slurry test yet.

That being said I think I might have figured out why my ph is so low. I was using the drops to test. Thought I was giving 6.5 but I got a pen and it’s showing low 5’s. So I have been feeding with way too low ph. Plus don’t know what the guys I purchased the plants from we’re doing.

What would y’all recommend I do to get my ph back up ASAP?? I don’t wanna lose these ladies!! Also wanted to let you know I’ve been dealing with fungus gnats, which also come with plants. Been using Gnatrol as recommended by guy at hydro store.
 

jumpincactus

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Many growers face a problem of a low pH of their soil. Some soils are acidic by nature and, in other cases, low pH is the result of prolonged and intensive fertilization and irrigation.

Soil pH below 5.5 might result in reduced yields and damages to the crop. Under these pH conditions, the availability of micronutrients such as manganese, aluminium and iron increases and toxicity problem of micronutrients might occur.

On the other hand, at low soil pH, the availability of other essential nutrients, such as K, Ca and Mg decreases and this might result in deficiencies.


In growing media, pH changes are much more rapid than in soils. Although various growing media are available with different baseline/starting pH levels, the effect of fertilization and irrigation on their pH levels can be enormous.

RAISING SOIL pH USING LIME
The most commonly used technique to raise the soil pH is applying agricultural lime. The Solubility of lime is relatively low, so if it is applied only to the soil surface, it usually affects only the top layer of the soil, not more than a few centimeters deep.

But which liming material should you use? What should be the lime application rate? Click here to more about how to choose a liming material and application rate.

In soilless media, lime should be incorporated into the media prior planting and the process is usually logistically difficult. Waiting until after planting only makes it more complicated, because the lime should then be individually applied to each growing container or each plant. Again, due to its very low solubility, it's impossible to apply it through irrigation.

RAISING SOIL pH USING POTASSIUM CARBONATE
Unlike lime, potassium carbonate is highly soluble and therefore can be applied by drip irrigation. Due to its high solubility, potassium carbonate can be easily distributed throughout the root zone together with irrigation water and reach deeper soil profile.

In both soils and growing media, potassium carbonate can rapidly affect chemical reactions in the root zone, thus elevate root zone pH.

Irrigation with water that have a low buffering capacity (low bicarbonate content) might drastically decrease pH levels in growing media. In this case, and especially when using inert media, pH drop can present a constant problem.

Applying potassium carbonate periodically, or even regularly, as part of the fertilization program, can prevent the pH drop.

POTASSIUM CARBONATE AS A FERTILIZER
Potassium carbonate also contributes potassium to the nutrient content of the irrigation water.
Therefore, potassium carbonate can be regarded as a fertilizer and its K contribution should be considered.

When applying potassium carbonate through the irrigation water, it is important to keep the pH below 7.0 in order to avoid emitter clogging.

Sometimes growers need to increase the buffer capacity of the irrigation water, while keeping pH levels low enough. In this case, it is possible to add potassium carbonate to water, and at the same time to acidify the water. The acid will neutralize some of the carbonate ions, while the pH level will still be low enough to prevent emitter clogging.

COMMON CAUSES FOR LOW SOIL pH

Prior to applying materials that increase pH, make sure that the low pH is not caused by an inappropriate fertilization regime. Often, an adjustment of such a regime may solve the acidity problem.

This is especially true for growing media (soilless media): ammonium/nitrate ratio is a major factor that can determine the media pH, and it can be controlled by proper a fertilizers application.

In soils, intensive fertilization with ammonium-based fertilizers or ammonium-forming fertilizers (urea) may lower soil pH.

Other factors affecting soil pH include:

Parent material - type of rocks from which the soil developed.

Rainfall - soils under high rainfall conditions are more acid than soils formed under dry conditions.

Soil organic matter - soil organisms are continuously decomposing organic matter. The net effect of their activity is that hydrogen ions are released and the soil becomes more acidic.

Native vegetation - the type of the native vegetation under which the soil was formed affects the pH of the soil. Soils formed under forest vegetation tend to be more acidic.


 

JWM2

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Olympus Up by nectar for the gods is a great way to raise your soils ph. It’s liquid lime. Calcium carbonate. Its about the only quick way to raise the soils ph with lime. Using regular lime is not hydrated and will take a few weeks to have any real noticeable effect. Powdered lime is great for soil mixes but not an additive. I’d suggest finding a local retailer that has Olympus Up and using that. Be warned though. It is potent stuff. So you don’t need much to have an effect. It’s best to raise the ph slowly over a number of days vs doing a flush and raising it all at once.
 
Olympus Up by nectar for the gods is a great way to raise your soils ph. It’s liquid lime. Calcium carbonate. Its about the only quick way to raise the soils ph with lime. Using regular lime is not hydrated and will take a few weeks to have any real noticeable effect. Powdered lime is great for soil mixes but not an additive. I’d suggest finding a local retailer that has Olympus Up and using that. Be warned though. It is potent stuff. So you don’t need much to have an effect. It’s best to raise the ph slowly over a number of days vs doing a flush and raising it all at once.
Thanks I’m ordering now! How would you suggest I use it? I’m watering with tap water. The ph is around 5.3 and ec of 115. Which thought it was 6.5 until I found out drops were off. Thanks for all your help!
 

JWM2

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Thanks I’m ordering now! How would you suggest I use it? I’m watering with tap water. The ph is around 5.3 and ec of 115. Which thought it was 6.5 until I found out drops were off. Thanks for all your help!
The directions on the bottle are pretty good guidelines. You could prolly use closer to 1tsp than 1/8tsp in your setup. Just watch your soils ph after a couple applications.
 
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I would be tempted to flush them with a low dose nutrient solution (0.5ec) with a ph of 6.5, Then give them a Full strength feeding. Start with RO and add 0.3ec Calmag. I wouldn't normally recommend this but those plants are old, and the soil is likely depleted of Ca. Plus it looks like you have both magnesium and Iron deficiency. Bring it up to 1.5ec with a good balanced base nutrient. Ph with potassium silicate.

I would also give them a foliar of just calmag, at about 0.1-0.2ec.
If it's in Pro-mix you should be able to re-buffer the ph without too much trouble just by appropriately adjusting the input ph and an adequate flush. If it's really stubborn you could top dress the pots with 2-3 Tbsp of dolomite lime each.

If you have a loupe, make damn sure those are actually just fungus gnats. 9 times out of 10 they are. But you should positively ID them to make sure they arent root aphids which can look quite similar to the untrained eye. Root aphids would also cause signs of deficiency. If it's just fungus gnats, use lots and lots of yellow sticky traps right at the soil surface. They're a nuisance but not really that harmful to the plant.
 
I would be tempted to flush them with a low dose nutrient solution (0.5ec) with a ph of 6.5, Then give them a Full strength feeding. Start with RO and add 0.3ec Calmag. I wouldn't normally recommend this but those plants are old, and the soil is likely depleted of Ca. Plus it looks like you have both magnesium and Iron deficiency. Bring it up to 1.5ec with a good balanced base nutrient. Ph with potassium silicate.

I would also give them a foliar of just calmag, at about 0.1-0.2ec.
If it's in Pro-mix you should be able to re-buffer the ph without too much trouble just by appropriately adjusting the input ph and an adequate flush. If it's really stubborn you could top dress the pots with 2-3 Tbsp of dolomite lime each.

If you have a loupe, make damn sure those are actually just fungus gnats. 9 times out of 10 they are. But you should positively ID them to make sure they arent root aphids which can look quite similar to the untrained eye. Root aphids would also cause signs of deficiency. If it's just fungus gnats, use lots and lots of yellow sticky traps right at the soil surface. They're a nuisance but not really that harmful to the plant.
Sorry for the question overload but when my meter is reading 115 ec is it actually 0.115? Also when you say add 0.3 cal mag does that mean on top of ec before adding? So total if I added to my tap water would be 0.415? I’m new to all this it’s kinda confusing!

Thanks
 
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Sorry for the question overload but when my meter is reading 115 ec is it actually 0.115? Also when you say add 0.3 cal mag does that mean on top of ec before adding? So total if I added to my tap water would be 0.415? I’m new to all this it’s kinda confusing!

Thanks
your tap water is probably 115ppm not EC, 115ppm would be about 0.2ec.

I wouldn't add calmag to tap water, only reverse osmosis water. You dont know what's in that 115ppm but it's likely a bit of Ca already with little or no magnesium/Iron.

With Calmag in RO at least you know the ratio of Ca/Mg/iron is correct.
 
I would be tempted to flush them with a low dose nutrient solution (0.5ec) with a ph of 6.5, Then give them a Full strength feeding. Start with RO and add 0.3ec Calmag. I wouldn't normally recommend this but those plants are old, and the soil is likely depleted of Ca. Plus it looks like you have both magnesium and Iron deficiency. Bring it up to 1.5ec with a good balanced base nutrient. Ph with potassium silicate.

I would also give them a foliar of just calmag, at about 0.1-0.2ec.
If it's in Pro-mix you should be able to re-buffer the ph without too much trouble just by appropriately adjusting the input ph and an adequate flush. If it's really stubborn you could top dress the pots with 2-3 Tbsp of dolomite lime each.

If you have a loupe, make damn sure those are actually just fungus gnats. 9 times out of 10 they are. But you should positively ID them to make sure they arent root aphids which can look quite similar to the untrained eye. Root aphids would also cause signs of deficiency. If it's just fungus gnats, use lots and lots of yellow sticky traps right at the soil surface. They're a nuisance but not really that harmful to the plant.
What potassium silicate do you recommend? I’ve been reading where GH can be dangerous if mixed wrong.
 
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263
What potassium silicate do you recommend? I’ve been reading where GH can be dangerous if mixed wrong.
Pure. My hydro shop gets it from a chemical supply company, its VERY thick stuff and yeah it can cause issues if you dont use it properly. You want to dilute it before adding to the res and add it very, very slowly stirring the whole time. It has such a strong ability to raise ph that added too fast or undiluted it will cause some nutrients to precipitate out of the solution.
 

jumpincactus

Premium Member
Supporter
11,574
438
Olympus Up by nectar for the gods is a great way to raise your soils ph. It’s liquid lime. Calcium carbonate. Its about the only quick way to raise the soils ph with lime. Using regular lime is not hydrated and will take a few weeks to have any real noticeable effect. Powdered lime is great for soil mixes but not an additive. I’d suggest finding a local retailer that has Olympus Up and using that. Be warned though. It is potent stuff. So you don’t need much to have an effect. It’s best to raise the ph slowly over a number of days vs doing a flush and raising it all at once.
Well said.
 
D45AC2D9-5AEF-4DB5-A1E7-96C0C9FDA98B.jpeg
If you have a loupe, make damn sure those are actually just fungus gnats. 9 times out of 10 they are. But you should positively ID them to make sure they arent root aphids which can look quite similar to the untrained eye. Root aphids would also cause signs of deficiency. If it's just fungus gnats, use lots and lots of yellow sticky traps right at the soil surface. They're a nuisance but not really that harmful to the plant.
I’m thinking you found my problem. Found this on one of my Cherry Moms today!!!! Found a few on other plants but not like the one in picture. I don’t really know what to do everything you read says something different. A lot say imid is the only way which idk might not be as bad for me since I don’t plan on flowering anytime soon. I’m planning to make 200-300 more moms off these moms. Might not flower these ladies till next year if I can get though these little creatures!!

Thanks for any help farm
 
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View attachment 857885

I’m thinking you found my problem. Found this on one of my Cherry Moms today!!!! Found a few on other plants but not like the one in picture. I don’t really know what to do everything you read says something different. A lot say imid is the only way which idk might not be as bad for me since I don’t plan on flowering anytime soon. I’m planning to make 200-300 more moms off these moms. Might not flower these ladies till next year if I can get though these little creatures!!

Thanks for any help farm
Yeesh, those look like regular Aphids. Are you seeing them in the soil or just leaves?
Is there any white chalky looking stuff on the top of the soil?

Imid will kill Aphids, no doubt. Something else that will is Botanigard 22 wp. If you are a long way from flower I would personally use both. But that's me. Pesticides make some people squeamish. I dont mind using them if they're used properly, and as a last resort.
 
Yeesh, those look like regular Aphids. Are you seeing them in the soil or just leaves?
Is there any white chalky looking stuff on the top of the soil?

Imid will kill Aphids, no doubt. Something else that will is Botanigard 22 wp. If you are a long way from flower I would personally use both. But that's me. Pesticides make some people squeamish. I dont mind using them if they're used properly, and as a last resort.
Not seeing any of the little green ones like on the underside of leafs in soil. I do see some little black winged bugs crawling through soil. Haven’t got them to be still enough to look at them with loupe. Just got sticky traps up this morning. Hopefully I’ll catch some so I can take a good look!! However I did see some of the little green one crawling around rim of pot. Not seeing any chalky looking stuff.

What Imid do you recommend? How much per gal. for soil? Also are you saying mix botaniguard 22 and Imid together and treat at same time?

Thanks for all your help
 
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Not seeing any of the little green ones like on the underside of leafs in soil. I do see some little black winged bugs crawling through soil. Haven’t got them to be still enough to look at them with loupe. Just got sticky traps up this morning. Hopefully I’ll catch some so I can take a good look!! However I did see some of the little green one crawling around rim of pot. Not seeing any chalky looking stuff.

What Imid do you recommend? How much per gal. for soil? Also are you saying mix botaniguard 22 and Imid together and treat at same time?

Thanks for all your help
When you catch some of the little winged bugs on the sticky traps post a pic. That sounds like either FG or RA. FG's wings will be the same length as the body. RA will have wings twice the size of the body.

I would recommend Merit 75 at 1/2 tsp per 5 gallons of water used as a soil drench. 2 applications 10 days apart.
That will kill 99.9% of them. The botaniguard I would spray on the leaves at the same time as the Imid application. I'd also apply it as a root drench a week after the last imid soak.

These are not cheap pesticides mind you. Botanigard 22wp costs $122 in Canada. probably more like $80-90 in the US.
And dont use Botanigard ES, try to find the 22wp. It has less phytotoxicity.
 
When you catch some of the little winged bugs on the sticky traps post a pic. That sounds like either FG or RA. FG's wings will be the same length as the body. RA will have wings twice the size of the body.

I would recommend Merit 75 at 1/2 tsp per 5 gallons of water used as a soil drench. 2 applications 10 days apart.
That will kill 99.9% of them. The botaniguard I would spray on the leaves at the same time as the Imid application. I'd also apply it as a root drench a week after the last imid soak.

These are not cheap pesticides mind you. Botanigard 22wp costs $122 in Canada. probably more like $80-90 in the US.
And dont use Botanigard ES, try to find the 22wp. It has less phytotoxicity.
Ok thanks for the info! When I look Merit 75 up I find Merit 75wp and wsp. I need the wp right?

I got a picture of one of the little black flyers I caught! Loving these little sticky pads! Also got a pic of an aphid crawling around rim of pot.

The last picture I’ve added is kinda worrying me. One whole limb has died! What is happening??? The crazy thing is I haven’t found hardly any Aphids on the leafs of this plant. Any Ideas??
 
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Its hard to tell from its contortion but that looks like a fungus gnat on the sticky trap. RA fliers have wings that are much bigger than their body. But the crawler on the pot looks like a root aphid, though it could be a regular aphid. Either way, Its clear your plants are suffering from uptake issues and it's a logical assumption to say something is probably chowing down on your roots. I'd be dropping the nuke. Merit 75 wp and wsp are pretty much the same thing, wp is wettable powder, and wsp is water soluble packets for large applications like golf courses etc... I'd get wp for sake of ease of use. Apply as a root drench and foliar spray at the rate of 1/2tsp per 5 gallons of water. Follow up with a second application 7-10 days later.

If you want to try a more "natural" fungicide first use botanigard. Personally I'd use both.
 

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