Brown thumb grow

[Gingerbeard]

Screw your probe.
You know what dry dirt feels like.

[Brwnthmb]

Just for reference, this is the plant I was just now asking about watering and the moisture meter. I did ignore the meter and watered it thoroughly.
My question is about the yellow spots you see on the leaves, mostly along the center line. The chart and drop down menu lists watering, ph, or nutrients as a possible cause. However, ph is around 7, and nutrients should be good. The soil is a relatively fresh potting soil and my other plants do not have this problem. The older leaves do have the problem more than the newer leaves. Do you think that this may be a holdover problem from the plant being overwatered in its early life? (I don’t know that it I was, but it stands a good chance. The seed germinated 7/22. The plant was transplanted to 3 gallon on 9/26.)

[Brwnthmb]

Screw your probe.
You know what dry dirt feels like.

I did ignore the probe and watered the plant.
thanks

[Rwise]

soil PH in veg is 6.2-6.5 in flower 6.5-6.8, again a PH of "around" 7 is "around" to high. Some plants can deal with it others cant, one pot may have got more of the buffers than another pot. Treat each one as an individual, and deal with its needs.

[Bluey]

Get your pH right and the plant will look after itself mostly. Get it around right and, well, your plant will be around right but never be right.

[Brwnthmb]

soil PH in veg is 6.2-6.5 in flower 6.5-6.8, again a PH of "around" 7 is "around" to high. Some plants can deal with it others cant, one pot may have got more of the buffers than another pot. Treat each one as an individual, and deal with its needs.

I have not yet upgraded my ph meter to an apera ph60 (or equivalent) as suggested by Bluey and Rwise et al, so I’m stuck with my old meter. Nevertheless, The ph reading for this plant and with this meter is 7.0.
I measured my other plants for comparison. Out of 9 plants, 7 had a ph of 7.0, one was 6.7, the other 6.8. (The 6.7 is one that is in flowering phase.)
So, the meter does seem to be repeatable. As far as accuracy I can’t say. ( I do plan to replace it with a better one. I just haven’t done it yet. Your advice didn’t fall on deaf ears.)

[Brwnthmb]

Thank you Rwise and Bluey

[Bluey]

You measure the pH inputs. Easy as. Don't bother with measuring runoff pH.

Don't ask me how to use a pH meter that is +/- 0.25. I'd bin it.

Apera have an Amazon store. Get storage fluid and calibration fluid in the same order.

If you are giving nutes also consider the PC60 instead of the PH60.

Don't bother with the Bluetooth model.

[Rwise]

You dont need to spend as much as I did on test equipment (My PH meter ran near $400 with supplies), but those cheap meters are just that cheap.

[Bluey]

The Apera Amazon store seems to be the go. US$94 for the kit

[Brwnthmb]

I can’t “refind” the information on dark green leaves, nitrogen, and flushing the soil, but I do remember that the solution to the problem is to flush the soil with water. I also remember plus 20%, but I don’t remember if this is the recommendation for watering normally or if the +20% is for flushing excess nitrogen. (Does anyone remember where in the drop down menu that this info is located?) thank you.

ps. I ran 6 liters of water through this one which is 20-100% more past the “pouring out” point, depending on where that is, 3 or 5 liters.
My hope is that I didn’t overwater it too bad. The leaves are curled up like a claw now. It’s a mystery to me as to how the soil knows when to let the water flush the soil and when to hold the water and cause problems.
Thoughts?

[Bluey]

Yes. Too much N.

Solution is to flush with water. pH it if you can around 6.3 and let it flush right through. You want a gallon of runoff or more.

You can't settle N out of the plant by flushing but van get it out ofyhe soil.

Are you feeding it nutes?

[Brwnthmb]

No I’m not using nutrients (other than what is in the soil already).
I just watered it (a lot, trying to flush out N as I explained), and the plant has just entered flowering stage. Do you recommend dropping the ph to 6.3 now? What are the benefits to dropping the ph now verses just letting the plant flower and finish its life with a ph of 7.0?

[Bluey]

Ok. Once it starts to flower (you see flowers) raise your pH slowly from what it should be in veg 6.2 to 6.5 to flower pH of 6.5 to 6.8.

Give it another flush. You want very little N in that soil heading into flower. You may need to suppliment some PK at ¼ to ½ strength at about 3 to 4 weeks into flower and keep that up for a bit.

[Brwnthmb]

Bluey thanks for the guidance. I wasn’t planning to add nutrients, but after learning more about it, I think I will. And adjusting the ph is needed. And I definitely need a meter.
I feel certain that a lot of nutrients have been used up in the plants (which are) blooming, plus I was planning to keep some other plants in the vegetative state for longer than normal. These will definitely need help. Thanks

[Gingerbeard]

Huh? I see a healthy looking plant. Looks better than mine! Seriously! I have pH tips. Where is your clawing? If those leaves mean you have Ntox, I have Ntox and have had Ntox in pretty much every plant I have grown since getting my groove together.
Are you giving more than recommended nutrients? Are you giving veg nutrients to still-hot soil?
Plants move and do things when they grow. I mentioned a time-lapse making a plant look like it was waving like a bird. That is not a joke. When you see plants turning colors other than green and taking other than fan leaf shapes, worry.
Now, check manufacturers recommendations. I know you're working with equipment issues. When it comes to flushing, that might not be the best toilet.

[Bluey]

He says the leaves are curly like a claw now, not shown on picture, but with that color I'd say too much N is the cause and he has flipped it so really need to get it out of the soil. That's my take on it anyway.

[Bluey]

You can't remove an excess of nitrogen from a plant by flushing the soil.

Your flushing the soil to remove the excess N from the soil as you don't want that going into flower.

Your plant is packed with N and if it needs some it can't get from the soil it will scavenge it from the lower leaves.

Edut. Yes flushing the soil will stress the plant. You do it once properly, not 6 times half hearted. It will recover quickly.

[Brwnthmb]

You measure the pH inputs. Easy as. Don't bother with measuring runoff pH.

Don't ask me how to use a pH meter that is +/- 0.25. I'd bin it.

Apera have an Amazon store. Get storage fluid and calibration fluid in the same order.

If you are giving nutes also consider the PC60 instead of the PH60.

Don't bother with the Bluetooth model.

I reconsidered and am going to use nutrients. You suggested the PC60 vs PH60 if using nutrients. Does the PC60 measure NPK as well as ph? (The apera website doesn’t say specifically.)

edit: the apera website does provide an email address and I sent the question to them. The PC60 measures TDS but the website doesn’t specify what the total dissolved solids are. [i’m looking for an instrument that measures nitrogen, potassium, and phosphorus in the soil.]

[Brwnthmb]

@Bluey
I suspect that I need to add nutrients for the bloom phase (and subtract nitrogen), but I don’t really know what nutrients I have left in the pot of soil. So, I thought it best to test the soil for nutrients (and ph) before I make adjustments.

[Brwnthmb]

Bluey
However; based on what you just said, I think it is wise to go ahead and add bloom nutrients. It will be the end of the week until I get an instrument to measure nutrients in the soil anyway and I received bloom nutrients this morning.
I have other plants that I plan to keep in vegetative state longer than normal, and I feel sure that they will deplete their nutrients. That is mainly what the instrument is for.
I have only grown outside before this.

[Bluey]

Best to watch it closely and keep your pH on point. First sign of deficiency I'd recommend adding bloom nutes at quarter strength, an NPK ratio of 1.1.2 from memory and maybe 2 to 5 weeks in a PK suppliment around 0.12.13 at half strength. That should keep you going pretty well. You shouldn't need to suppliment PK for more than a few weeks and every second feed probably fine. Don't give runoff every feed. A bit of runoff twice a week is plenty most of the time.

Watch your leaves closely and keep pH in a range of 6.5 to 6.8 once flowers appear. Increase nutes a little each week until maybe at 3/4 strength. I've never had to go higher than that in coco.

Edit. I have had to start PK prior to flowers appearing but it will vary depending on how your plants are travelling.

[Brwnthmb]

I am very happy with my plants and I hesitate to do anything, but they are just starting flowering and are ready for bloom supplements.
I just received the bloom supplement (pictured). This brand was one of the ones recommended. Therefore I feel sure that I can make it work in the ratio that you are specifying.
Thank you for your help.
[the (2) 3 gallon fabric pots are the main ones. The two clay pots started flowering at the equinox, and I just brought them in for frost protection.]

[Brwnthmb]

@Bluey
When you say “always vary the ph inputs within the recommended range” (or something to that effect) do you mean just to always stay within the recommended range?, ie don’t go outside the range (of 6.5-6.8) to try and correct for a too high or a too low ph?
Edit (added); I remember seeing a chart on here somewhere that shows the relationship between ph and nutrients absorption (the ph range for nitrogen absorption, for example), but I can’t locate it now. Do you remember where that is?

[Bluey]

There's a few charts available so make sure you download the one for the medium you are using.

The pH of the soil won't change much, but you need to vary it in hydro to allow for a balanced take up of nutes so I'd say it's good practice to vary it in its recommended range. You shouldn't need to go outside that range unless your soil is out of range but assume it's good. Just watch your leaves very closely, from the bottom to the newest top ones for changes in color and shape. Taking photos can help with that.

Do you have enough light?

Take some close up of where the buds will start forming looking closely for the formation of pistols.

When do you plan on adding nutes to your water?

[Brwnthmb]

@Bluey
I’ve been adding bloom nutrients to those in bloom phase and veg nutrients to those in worn out soil, judging from yellowing leaves and too much time since repotting. So, to answer your question, I already am adding nutrients. Today was the first day that I got the ph correct before pouring in the bloom nutrient mix. I expect healthier leaves now.
My tap water is over 7, so if nothing else it needs some ph down. I do have a recurring problem of dark green leaves, and the soil is only a month old. I’ve noticed that the plants which get the dark green leaves get light bags quickly (they are thirsty). That seems to me to be a healthy sign.

[Gingerbeard]

You got something wompus about your before-and-after nutrient pH.
I did a little google and found the answer "No, Superthrive Bloom is a plant nutrient designed to be used during the flowering stage of plants and does not lower pH."
When did this start, or, when did you notice this? Have you upgraded your pH meter? If your pH lowers with the more you add, are you adding too much in the first place?

[Gingerbeard]

Flat, yes. But you need air to the bottom of the bags just as you need it to the sides. They need to breathe or your chance of root rot goes up.

[Brwnthmb]

Thanks for the tip on elevating the bags! I would never have thought of that. Do you also discard the black plastic saucers that fit onto the bottom?

[Brwnthmb]

Thanks for the tip on elevating the bags! I would never have thought of that. Do you also discard the black plastic saucers that fit onto the bottom?

[Brwnthmb]

Gingerbeard
i think I’m using the meter correctly; and it’s a vivosun meter (the cheap but recommended one). I measured the before and after the same way, suspended in a one liter pitcher.
However , the calibration didn’t go exactly like the manual said it should, that the meter would get to 5, then blink 3 times, etc. so I don’t feel confident in the calibration. However the readings are very repeatable when measuring tap water, and the sample at 6.86.

edit; I am trying to add 1/2 tsp/ gallon (0.5ml/750ml) but the syringe that I’m using is hard to read.

[Bluey]

1 US gallon = about 3800ml or just under 4 litres. 750ml is a bit under a US quart which is 948ml

1 imperial gallon is a bit over 4 litres. 1 imperial quart is 1.13 ltrs

Something like that.

Edit. Zoom on using your phone on the syringe and put some blue tape or similar at 2ml 4ml or 5ml 10ml then you can keep putting off those reading glasses like me.

[Bluey]

Read this

https://forum.growweedeasy.com/forum/growing-community/587080-the-tale-of-two-ph-pens#post587080

Get an Apera PH60 or PC60 with calibration fluid and storage fluid.

They have a shop on Amazon.

Toss that POS in the bin once it arrives.

[Brwnthmb]

@Bluey
I have a ph60, but haven’t used it yet. (I also ordered the vivosun “model pos” since it was cheap and recommended.) I will try the apera when I get home for comparison.
I expected the Vivosun to calibrate as advertised at least. There’s some reason it didn’t get to and stop at 5. It’s also a puzzlement how it was repeatable afterwards measuring tap water and the sample’s ph.