Ph and fertilizer

[PastryBaker]

Happy Labor Day to all in the states.

I have to adjust my water ph when I water. When I am going to fertilize should I add my fertilizer to the water first and then adjust the ph? Or adjust the ph and add the fertilizer and then recheck?

Thank you.

 

[BrianBay9]

Some fertilizers can alter pH, so better to add first, then adjust if necessary.

 

[Rodrigo]

The way I do it is to add the fertilizer and then check the ph. The fertilizer most likely will change the ph so there's no point in adjusting before adding it

 

[Gabler]

Why are you adjusting the pH when you water? Is it too acidic or too alkaline? Were you noticing problems with your plants before you began adjusting the pH?

 

[Glaucus]

It will change the pH. But probably not by much. If you have typical hard water, lower the pH to say 6.0, then add a normal amount of fertilizer, the pH probably will be about the same.
But if you do something else, like set the pH to 10.0, add a ton of fertilizer so that it is barely soluble, then measure if it is still 10.0, it probably no longer is. Of course that's not what you are doing. But also not what you specifically ruled out.
Since you have the ability to measure the pH, why not try and measure fo r yourself how much it has changed?

Most fertilizers are blended to bring the pH to the 6.2 to 6.5 range, because in that range everything is soluble and plant uptake is good. At higher pHs, fertilizer components might form non-soluble salts with the calcium in your tap water, biggest candidate being calcium phosphate.

So to answer the 'why do you want to lower water pH', if you are mixing in fertilizer you definitely want to consider that. It is not going to be significant, because your fertilizer is likely quite dilute. But if you are growing 200 tomato or pepper plants, and you are setting the pH anyway, and you are feeding way more than you would feed a bonsai, it is a bit silly to do all this work, and have quite a bit of the phosphate become a solid before you even poor it onto the soil. Because your tap water is pH 8.5 and high in calcium2+.

 

[PastryBaker]

Why are you adjusting the pH when you water? Is it too acidic or too alkaline? Were you noticing problems with your plants before you began adjusting the pH?

Way too alkaline. Almost at 9. I thought my one tree's problems were from sun damage and I used shade cloth. But still was not doing great. A couple said that to check the water. The water out here can be pretty bad. High ph and lots of dissolved solids.

 

[PastryBaker]

It will change the pH. But probably not by much. If you have typical hard water, lower the pH to say 6.0, then add a normal amount of fertilizer, the pH probably will be about the same.
But if you do something else, like set the pH to 10.0, add a ton of fertilizer so that it is barely soluble, then measure if it is still 10.0, it probably no longer is. Of course that's not what you are doing. But also not what you specifically ruled out.
Since you have the ability to measure the pH, why not try and measure fo r yourself how much it has changed?

Most fertilizers are blended to bring the pH to the 6.2 to 6.5 range, because in that range everything is soluble and plant uptake is good. At higher pHs, fertilizer components might form non-soluble salts with the calcium in your tap water, biggest candidate being calcium phosphate.

So to answer the 'why do you want to lower water pH', if you are mixing in fertilizer you definitely want to consider that. It is not going to be significant, because your fertilizer is likely quite dilute. But if you are growing 200 tomato or pepper plants, and you are setting the pH anyway, and you are feeding way more than you would feed a bonsai, it is a bit silly to do all this work, and have quite a bit of the phosphate become a solid before you even poor it onto the soil. Because your tap water is pH 8.5 and high in calcium2+.

My tap is sometimes almost 9. And lots of TDS. It is at 390. The water out here is not the best.

 

[Gabler]

I solved a similar problem with Holly Tone fertilizer.

 

[Rodrigo]

I solved a similar problem with Holly Tone fertilizer.

Can I ask what that does? Lower the ph? I use a siphon to a bucket of super low ph and it's honestly a headache so if this is easier I may try it lol

 

[Bonsai Nut]

If you are going to adjust your water, I would recommend doing so uniformly - ie through filtration or water treatment (like reverse osmosis or water softening). I would NOT recommend trying to treat each bucket of water that you put on your trees - you will go insane in short order. Success in bonsai is all about keeping things simple.

However even with crappy water, you will see an improvement if you use acid fertilizer particularly if it also supplements iron. The soil acidifier I saw used most often in SoCal was elemental sulfur. I use this chart all the time, so I apologize if you have already seen it. However I think it clearly illustrates how high pH impacts the ability of your trees to take up iron, manganese, copper and zinc.

 

[PastryBaker]

If you are going to adjust your water, I would recommend doing so uniformly - ie through filtration or water treatment (like reverse osmosis or water softening). I would NOT recommend trying to treat each bucket of water that you put on your trees - you will go insane in short order. Success in bonsai is all about keeping things simple.

However even with crappy water, you will see an improvement if you use acid fertilizer particularly if it also supplements iron. The soil acidifier I saw used most often in SoCal was elemental sulfur. I use this chart all the time, so I apologize if you have already seen it. However I think it clearly illustrates how high pH impacts the ability of your trees to take up iron, manganese, copper and zinc.


View attachment 566050

Thanks...I only have a few trees and orchids so it make a quick few gallons of just regular water. And adjust. It pretty much is the same measurement of citric acid every time. In my real career I am a pastry chef for 20 years, so measuring is an every day thing...lol Now when I have many trees, I am sure I will rethink that. I did attach one of these that helps make the water a little better. I think it was you who showed me how to look at my water report.

 

[Gabler]

Can I ask what that does? Lower the ph? I use a siphon to a bucket of super low ph and it's honestly a headache so if this is easier I may try it lol

The soil acidifier I saw used most often in SoCal was elemental sulfur.

Holly Tone is a granular fertilizer mixed with chips of sulfur. It comes in gigantic bags for fertilizing acid-loving trees in the ground. My azalea, sweetgum, oak, beech, and maple trees all seemed to like it. They were a much darker green. Other species were indifferent to the pH change. I'm now on well water, so I don't need to use it anymore.

 

[Jrmcmich]

Thanks...I only have a few trees and orchids so it make a quick few gallons of just regular water. And adjust. It pretty much is the same measurement of citric acid every time. In my real career I am a pastry chef for 20 years, so measuring is an every day thing...lol Now when I have many trees, I am sure I will rethink that. I did attach one of these that helps make the water a little better. I think it was you who showed me how to look at my water report.

I have Similar bad city water with TDS of over 500. I tried one of those filters as well. Lowered slightly but not much. I ended Up getting a 275 gal tote on facebook marketplace and now collect rain water from roof.

 

[PastryBaker]

I have Similar bad city water with TDS of over 500. I tried one of those filters as well. Lowered slightly but not much. I ended Up getting a 275 gal tote on facebook marketplace and now collect rain water from roof.

I wish I could collect rainwater. But here in the desert, I would maybe get a gallon a year.

 

[Sixty’s]

Reading through the tread I would say that your best option would be a RODI unit. This should bring your ph down and TDS to zero. Alternatively if you don’t want to make that investment just yet look at aquatic shops near your area most of them will sell RODI water.