Deficiency or burn?

[DTOM420]

I just fed these autos for the 1st time at day 37 - today is Day 39. Gave them a 1/2 dose of 6-12-6 organic liquid nutes and pH’d to 6.3. Soil pH is 6.4. Temps 74° during light hours and 71° at night; with RH around 55%. This puts me in the proper VPD range.

You can see the brown tip on the plant’s oldest leaf which was present BEFORE I fed and was the reason I decided to feed some nutes. All the tips are showing a little brown (burn, I think?) but some are curling upward. Especially near the top. A few leaves have some brown spots near the tips:

Here’s the other girl. Same age and conditions. She is showing similar brown tips over past 2 days but she’s also showing some brown along the serated leaf edges. Same brown spots on a few leaf tips:

Can anyone identify a deficiency or is this burn only? It’s possibne that that old leaf on the first plant is a symptom of a root hitting a hot spot in the soil and by seeding this soil mixture (that should have plenty of nutrients in it) made things too hot. Just trying to get a handle on it early.

@Waira

 

[Rev. Green Genes]

Burn. Ease off the nutes for minute, and maybe raise the light for a cycle. Check pH if you can, burn can be a symptom, or an issue in and of itself.

 

[HashMaster]

Deficiency and perhaps a touch of lockout action going on I'm betting.....

I enjoy reading @Waira cures... only reason I stick my nose in this section actually...

I bet he will be along soon...

 

[DTOM420]

Burn. Ease off the nutes for minute, and maybe raise the light for a cycle. Check pH if you can, burn can be a symptom, or an issue in and of itself.

That would be my thought 100% if I hadn’t had that one old leaf (top picture) with the symptom before I gave it the first nute feeding. And the fact that I only fed 1/2 strength. Sure seems like the most obvious solution, though, since it popped up everywhere else right after the feeding.

PH of soil is 6.5 and nutes were pH’d to 6.3. So, I dont see how this could be a pH lockout.

 

[Waira]

:smoking: well, I don't like coincidences, and while half dose of organics shouldn't have caused this, it's likely so,... How rich is this soil, what brand? And the nute, which brand as well? 6-12-6 is pretty rich for organic liquid based,... ...weird pattern, looks like K defc as well along the margin teeth, seemingly contrary!

 

[DTOM420]

:smoking: well, I don't like coincidences, and while half dose of organics shouldn't have caused this, it's likely so,... How rich is this soil, what brand? And the nute, which brand as well? 6-12-6 is pretty rich for organic liquid based,... ...weird pattern, looks like K defc as well along the margin teeth, seemingly contrary!

Thanks for looking, @Waira. Soil is a mix:

2 gallons Pro-Mix vegetable
.5 gallon coco
.5 gallon Mushroom compost (bag)
.5 gallon composted chicken manure (bag)
.5 gallon worm castings
1 gallon perlite
1 cup alfalfa meal
5 tbs Mex Bat Guano
5 Tbs Seabird Guano
1 cup dolomite lime
3 tbs Rock Phosphate
.5 cup bone meal
10 tbs bone meal
5 tbs blood meal
1 tbs granular humic acid

I’ll PM you a link to the 6-12-6 nutes. For what it’s worth, it’s a very popular organic fertilizer used for all sorts of gardening in our region. There isn’t an organic oriented nursery/supply store within 150 miles that doesn’t use, support and sell it; and a bunch of tomato growers (like me) have used it outdoors with great success. Now, that doesn’t mean it’s going to be good for canna. I had some issues with other plants that I’d been using Mega Crop on and I decided to try some of the 6-12-6 I had laying around. I’m trying to isolate what I’m doing wrong. Lol! 95% of my issues are in my inside grow. Outdoors I had very little issues. Indoors....ugh!

 

[DTOM420]

Burn. Ease off the nutes for minute, and maybe raise the light for a cycle. Check pH if you can, burn can be a symptom, or an issue in and of itself.

Thanks Rev! Soil pH is 6.4 and I’ve been watering with 6.3.

What causes pH fluctuations in soil? I mean, I’ve read some references to soils having a sudden rise or fall mid grow. Besides a buildup of nutes, which I assume might lower pH, what would case a sudden change within a batch of soil mixture (like the one I posted above) to suddenly change? Been wondering about that.

 

[Natsu]

As Waira mentioned, it looks like a K def. to me as well. On my first grow I was using Gia Green living composted soil, my ph dropped to 5 and I ph'ed everything that I put in to 6.5 so I was kind of confused as to why it would drop like it did, so I'm not sure what would cause that either.

 

[DTOM420]

They’re looking worse today. I gave them each a 1/2 gallon of water pH’d to 6.3 with a dose of Sledgehammer. Checked soil pH before that and it’s hanging at 6.4. It’s a little early for more water but, if it’s something with those 6-12-6 nutes I fed, maybe the Sledgehammer and pH’d water will help flush it out some, what’s weird is that the symptoms don’t seem to be exactly the same here.

Grrrrrrrt! This is SO agrivating.

Plant1 has major leaf tip curling and the yellowing is widespread, along the edges and the tips of the leaves:

Plant 2 has a lightening of the leaves along the veins:

As Waira mentioned, it looks like a K def. to me as well. On my first grow I was using Gia Green living composted soil, my ph dropped to 5 and I ph'ed everything that I put in to 6.5 so I was kind of confused as to why it would drop like it did, so I'm not sure what would cause that either.

I have another plant that’s a photo I’ve posted about in here that suffered a major pH drop in the soil but THIS plant’s pH has remained stable and was still stable today. I just don’t see how it could be pH related when the Accurate 8 is showing steady at 6.4 and I’m feeding 6.3. Maybe it IS a K deficiency but look at the Seabird Guano I included in the soil. I wouldn’t think a 40 day old plant in that mix could be K deficient. Heck, I do t see how it could be deficient in anything. Lol!

What would you suggest feeding?

These are the nutes I have on hand:

FoxFarm Big Bloom 0-0.5-0.7
FoxFarm Tiger Bloom 2-8-4
FoxFarm Grow Big 6-4-4
Greenleaf Bud Explosion 0-23-44
Kelp meal
Root Organics HPK 0-4-3
MegaCrop 9.7-5.5-

Hoping el jeffe @Waira will check back in also.

 

[Rev. Green Genes]

Thanks Rev! Soil pH is 6.4 and I’ve been watering with 6.3.

What causes pH fluctuations in soil? I mean, I’ve read some references to soils having a sudden rise or fall mid grow. Besides a buildup of nutes, which I assume might lower pH, what would case a sudden change within a batch of soil mixture (like the one I posted above) to suddenly change? Been wondering about that.

Thats a complex problem, and it starts with what type of soil mix you have. The pH we measure is Active pH, but the more important measurement is Buffer pH which is the latent buffering capability inherent to that soil type/formation. In a field condition it takes a long time to change pH because of the buffer capability, you can think of it as infinite lime or infinite sulfur. In pots however, the buffer is not so strong unless you are using clay or silty soils.

Inside that pot all the little microbes are using nitrogen, and if you have a strong microlife community, they can bind up a lot of Nitrogen, causing the soil pH to temporarily spike. It then changes back as the microbes die and release that N back to the soil. Or you can have other reactions between nutrients as they shift form in the soil. Coco can play havoc with pH, because it attracts so much nutrient to it, it can leave areas of the pot with differing pH. If you have chlorine in the water, it can react funny. If there is sodium salt present than it can bind up nutients in solution and they leach. There are dozens of ways. The main point is that soil chemistry is not simple, and every thing you add, and what you started with will always react and change over time.