PH Wert der Erde

Hi GroW’s

I’ve had a drastic problem with my pH level for about a week now. It dropped from 6.3 to 5.63 & to 5.47.

During that time, I watered 2x with a 3-day interval. 1x 4L with 3.0ml Cal/Mag + 24ml bloom fertilizer pH 6.4 & 1x 4L with 3.0ml Cal/Mag + 24ml bloom fertilizer pH 6.7

In a 15L fabric pot. What is the best thing I can do? Cut the fertilizer in half or leave it out completely & only add water with Cal/Mag? Is it better to raise the pH level slowly or immediately?

I hope you have a few useful tips for me.

Magic

Which pH? The irrigation water or the substrate pH?

If you are chasing run off or medium ph you are setting yourself up for a headache in my opinion. I measure the ph of what goes in and never give it any more attention unless the plant says something is wrong which yours is not doing from the look of it. If it isn’t broken don’t fix it basically.

Ok Thx

Since I have a fabric pot, it’s probably better anyway to water max. only until runoff drops come out. Then stop. Because with fabric pots with soil, it’s supposedly better if no runoff comes out.

I actually always keep my watering water​ at 6.0-6.5 pH. My EC is actually fine too, usually between 0.97-1.25

But how do I find out e.g. the pH value of my plant​? Because that tells me how well it absorbs its nutrients. I need that value, don’t I?

Magic

Hi

A question: I have to water again tomorrow, Fri. 28th. And my pH level is still at a dramatic 5.47​

So my question is, should I water with or without fertilizer, or just 1/2 dose, and/or just plain water + Cal/Mag? And should I raise the pH level slowly to 6.0-6.3 first or rather raise it to around 7.0 right away?

I urgently need some info so my lady can absorb enough nutrients again.

Magic

After a long time, I switched from Biobizz soil to Plagron Growmix, using Plagron Lightmix for seedlings. Completely different plant behavior.

I also had a pH value of 5.7 in the drain once, and the plant showed signs of deficiency/over-fertilization.
The whole thing was due to the many salts that built up from the fertilizers.
Just keep watering consistently with a pH of 6.5. It takes a week or two for it to regulate in the medium again. I find a pH value of 5.8 to be very borderline. From 6.3 down, it becomes extremely difficult for the plant to absorb calcium and magnesium. This usually ends in a lockout with signs of deficiencies. Incorrect watering is also a very common reason. (Better less and more often than too much, at least in the beginning)

I discovered interval watering for myself in the larger pots.
First moisten everything with a sprayer, wait 10 minutes, repeat, wait 10 minutes, and then I pour my 7 liters in 500-1000ml increments every 10 minutes into the 20-liter pot until I have 10-30% drain. With fabric pots, salts like to build up on the inner edges of the pot. This way you prevent dry spots.

Drain is therefore important if you use mineral fertilizers. With organic, it’s secondary.

Your plant looks healthy, as others have already said. Don’t worry so much.

After doing some translation on your substrate It is primarily coco from what I can see which means your target ph is actually 5.8 which the mix started at, it also contains some slow release nutrients by the look of it which is going to mess with the numbers a bit if you are checking. If it was me i would feed at 5.8 and not worry about it any further

Your plant is clearly happy with what it is getting so i don’t see it as a problem

My pH value: 5.47 This is my soil:

So my question is, should I best water with or without nutrients, or only 1/2 dose, and/or only plain water + Cal/Mag? And should I raise the pH level slowly to 6.0-6.3 first and then back to normal 6.0-6.5 next time, or would it be better to raise it right away to about pH 7.0? Or is this too big of a shock?

I still don’t understand which pH you’re measuring, whether it’s the watering water with or without fertilizer—doesn’t matter to me—or if you’re measuring the pH of the substrate, or the runoff tray. I really don’t understand what you’re measuring.
If you mean the watering water, you bought an All-Mix, you shouldn’t feed/fertilize, not because of the pH, but because the substrate already has plenty of fertilizer. Still, if you want you can fertilize; if the plants don’t show burnt tips, it means there’s no excess of salts. (high EC)
If what you mean is that when you add fertilizer to your water, the pH drops, you’re probably using mineral fertilizer, PK, or similar, which have high acidity. In that case, what you need to use is pH+, to raise the pH of the water.
If the substrate pH is what is acidic, at 5.x you can raise it simply by watering with the pH adjusted to 6.5/4/3/2

Ah, I understand.

I meant the pH 5.47 from the runoff.

But based on what you said about organic fertilizer lowering the pH, it must be my fertilizer.

Should I leave it out completely for the next watering? Or better just 1/2?

Yes, your bloom fertilizer is mineral, NOT organic.
Both are mineral, although I’d swear I read other posts of yours where you talk about organics, I don’t know if it was you, but they are mineral.
Just measuring the pH before watering is enough.
P.S.: measuring the runoff pH is not effective, it’s not a real measurement, it’s something done “by eye” to “get a rough idea”, you shouldn’t take it as a reference for anything.

Ok thanks

I can also measure the pH value differently. I could put 50/50 soil/distilled water into a sealable container. Shake well for 1 min so everything dissolves. Then let it sit for about 5 min until almost all the soil has settled. Then measure the pH/EC value from the surface of the resulting liquid. And just like that, you have the pH/EC value of your plant’s soil.

Magic

ok, from my point of view it’s still just a distant approximation, the pH is different in every part of the pot, I have substrate meters and I know why I say it

Ok Thx

Magic

What do you think about flushing?

I currently have a dramatically low pH level of 5.09, and that’s why I did a bit of research and found out that I should just flush my 18L fabric pot with about 6L. What do you think, will this really raise my pH level?

Or do you maybe have another emergency measure?

Magic

Good morning !!! and the EC values it shows you? they are high, right?

Hi

So my watering water has the values: PH 6.53 / EC 0.34

My runoff has the values: PH 5.09 / EC 2.03

Today I also watered without fertilizer or booster, just with Cal/Mag & Downer adjusted to 6.5 PH.

Do you think I should flush next time I water? I usually water with 4l and would then flush with 6l. What do you think?

Ok regards

Magic

Look, with that runoff EC at 2.03 mS/cm, you don’t have severe over-fertilization to warrant doing a root flush; the main problem isn’t the salts, but that your substrate pH dropped way too low. If you do a 6-liter flush with plain water, you’re going to make things worse because you’ll drown the roots and you could throw everything off balance without solving the acidity. So, I’m no big expert, but in your place, I’d keep your usual watering volume without drowning her, put away the pH Down for now without adding any acid to the input water, water with a higher input pH of 6.8 to 7.0 to gradually push the soil acidity up, add a level tablespoon of dolomite lime sprinkled over the substrate and water over it to raise the pH quickly and stably, and manage the fertilizer carefully at your own discretion based on what you’ve been using, but without going crazy with plain water flushes so you don’t leave the medium stripped of everything.

So you mean next time I should go ahead and water like today again, 4l with just Cal/Mag & pH at 6.5?

And that will make the pH value rise again?

The EC value is clear to me because of more or less fertilizer.

I hope I can still get this under control!