Spots appearing - need help

[Cwmoore577]

Ok, so I have a pretty basic closet set up with a single 600w full spec light, Temps are usually 70-80 but exact humidity unknown.
Soil is FoxFarm Strawberry Fields which I read that people have had problems with also.
Plants are still vegging at 9 weeks old.
I have General Organics BioThrive grow for nutrients (4-3-3) and gave the plants a half strength dose about every third watering in weeks 4 to 6.
Originally had some curling under/clawing and chlorosis. Thought it might be Nitrogen tox at first so after I transplanted to bigger containers I cut the liquid nutes out and just watered them with pure distilled water for weeks 7-9 on about every third day. They started doing better after the transplant and then started to see some interveinal chlorosis so I gave a half strength dose of calmag twice in the past 2 weeks thinking it could be mg deficiency.

Now I’m starting to see some more curling, brown spots, and reddish/purple stems.

Any suggestions of what I need to do or stop doing?

Also going to test runoff pH today to see if that may be an issue. I will edit those results.

 

[boilingoil]

Plant size to bucket size, please? Are you lifting the pot to check for water content or just going on a 3 day watering cycle? Old growth will not show improvement, check that newer growth isn't having problems.

 

[Cwmoore577]

Plant size to bucket size, please? Are you lifting the pot to check for water content or just going on a 3 day watering cycle? Old growth will not show improvement, check that newer growth isn't having problems.

I’d say they’re about 2.5 to 3ft tall and in 5 gal containers. I do try to get a measure by checking weight but mostly I use a moisture meter and check to see if it’s dry 2-3 inches in the soil. And yes, the clawing, curling under, brown spots, reddish stems developed on newer growth recently. The first two pictures are of the top fan leaf.

 

[boilingoil]

I’d say they’re about 2.5 to 3ft tall and in 5 gal containers. I do try to get a measure by checking weight but mostly I use a moisture meter and check to see if it’s dry 2-3 inches in the soil. And yes, the clawing, curling under, brown spots, reddish stems developed on newer growth recently. The first two pictures are of the top fan leaf.

Your probable over watering. Easiest way to see mag diff is over watering or using LED's

 

[CanadianJim]

Moisture meters can be useful, but only if they reach deep enough into the soil. And they're more of a ballpark. Weight is better. Does the cal/mag have N? I seem to remember that some of them do.

 

[Cwmoore577]

Moisture meters can be useful, but only if they reach deep enough into the soil. And they're more of a ballpark. Weight is better. Does the cal/mag have N? I seem to remember that some of them do.

Yes the NPK of the calmag is 2-0-0. And thanks I’ll keep that in mind.

 

[Cwmoore577]

Your probable over watering. Easiest way to see mag diff is over watering or using LED's

So watering less should fix the issue? Also I pH’ed my runoff which is low at 5.3. Could that be an issue?

 

[Renfro]

So watering less should fix the issue? Also I pH’ed my runoff which is low at 5.3. Could that be an issue?

Yes. Think you found the problem. You want 6.5 - 6.8 going in and something not too far off coming out. You may have salt buildups in the soil. Do you water to get 20% runoff everytime?

 

[Cwmoore577]

Yes. Think you found the problem. You want 6.5 - 6.8 going in and something not too far off coming out. You may have salt buildups in the soil. Do you water to get 20% runoff everytime?

Well I get runoff every watering but idk if close to 20% comes out, definitely not every time. Like last night I gave each container like 32 oz of pure distilled and a small amount drained so that I could stick the ph pen in. Then I added 16oz of the distilled water w/ calmag in it. 24-32 oz is about how much they get every watering.
Tested the runoff last night.. water measured 6.7-6.8 going in and the bit I got out the tray was 5.3 for each plant.

Can you get salt buildup while watering with mostly pure distilled?

 

[Renfro]

Pure distilled is bad for plants. You cant buildup anything with 0 ppm water. Adding a little calmag is required for sure when using distilled h2o. at those levels of PPM input you shouldnt have any significant buildups.

So you are watering with distilled water? May I ask why?

I wish I had one of my soil pH pens (the digital ones) there to test that soil. I suspect it's pretty wack on the pH.

 

[Renfro]

Soil is FoxFarm Strawberry Fields which I read that people have had problems with also.

I think this is where the issue may be. What symptoms / issues do they describe?

 

[Renfro]

I have had fairly good luck with soil that had a really high or low pH using a pH thats going to offset that and try to swing the pH the right direction. It's not scientific and is totally a guessing game but may help nutrient uptake enough to save the crop. So say the soil is pH 5 and you want 6.5 then feed at say 8.0 to try and get the numbers to balance out. Totally not scientific but I have used this to save a crop. You have to watch the plants for signs and adjust... pretty crappy situation when you are stuck in a bad mix.

 

[Cwmoore577]

I have had fairly good luck with soil that had a really high or low pH using a pH thats going to offset that and try to swing the pH the right direction. It's not scientific and is totally a guessing game but may help nutrient uptake enough to save the crop. So say the soil is pH 5 and you want 6.5 then feed at say 8.0 to try and get the numbers to balance out. Totally not scientific but I have used this to save a crop. You have to watch the plants for signs and adjust... pretty crappy situation when you are stuck in a bad mix.

Well for one a guy on here said he used FFSF and his plants “burned to shit” is what he said.
Also, I just left the hydro garden store here in town and the guy there suggested that it could be russet mites. Any idea if he could be right? I spotted a couple mites after looking it over with a magnifying glass. Really tiny, but I did find them not 100% that they’re russet. I bought some Green Cleaner Insecticide and going to douse them tonight when the lights go off.

 

[Bernie420]

So watering less should fix the issue? Also I pH’ed my runoff which is low at 5.3. Could that be an issue?

You water correctly to fix watering issues

dont ever check run off ph its pointless and makes you do stupid shit.

get a microbe product

Feed water water feed , microbes once a week.

When somebody says it could be or I think so, its just another way of saying they dont know.

 

[Budzbuddha]

Overwatering..... let plant dry better .... see how many days it can go BEFORE watering instead of a schedule. I personally hate distilled water ... seems ridiculous since I water my outside tomatoes / chilies / flowers with hose water. The whole idea of using “ stripped “ water ( cal / mag , etc. removed ) then trying to reintroduce it .... just complicates things.

Does your lawn need distilled water ?

As stated ... checking runoff is also ridiculous ( since you have to OVERWATER just to get runoff ) .
If you ph what you are adding to the plant ( and it’s at mediums preferred range ) then you are set , no checking shit is needed.

Overwatering actually leaches the medium ( strips ) and that’s where shit start showing up.

 

[Cwmoore577]

Overwatering..... let plant dry better .... see how many days it can go BEFORE watering instead of a schedule. I personally hate distilled water ... seems ridiculous since I water my outside tomatoes / chilies / flowers with hose water. The whole idea of using “ stripped “ water ( cal / mag , etc. removed ) then trying to reintroduce it .... just complicates things.

Does your lawn need distilled water ?

As stated ... checking runoff is also ridiculous ( since you have to OVERWATER just to get runoff ) .
If you ph what you are adding to the plant ( and it’s at mediums preferred range ) then you are set , no checking shit is needed.

Overwatering actually leaches the medium ( strips ) and that’s where shit start showing up.

Ok I’ll keep that in mind and water less. What do you think of the mites found? Didn’t find many but could they be causing anything as well?

 

[pulpoinspace]

imo the picture doesn't look like typical mite damage but if you found mites i would try to get rid of them before its too late.

 

[Cwmoore577]

imo the picture doesn't look like typical mite damage but if you found mites i would try to get rid of them before its too late.

It does have a few leaves that kinda look like russet damage with the curled up edges that resembles heat stress.

 

[grohkingg420]

Any help appreciated. Starting to see more and more leaves like this by the day. Can’t see any bugs by the bare eye. Wondering what is causing this and remedies to cure. 30 gallon pots , promix soil. Botanicare grow nutes and some calmag being used.

 

[CanadianJim]

Those look like either leafhoppers or four lined plant bug. Since the insecticidal soap I use needs you to hit it directly, you'll probably want to use neem oil. I've never used it but from what I've read it leaves a residue that keeps them away.