420 Fastberry day 45 - Nute burn on serrated edges?

[Duceduck]

I went through 4 pages just to make sure this has t been posted recently.

Strain: 420 Fastberry
Medium: 2 gallon HF amended with WC, Kelp, and Dolomite lime
Temp: 75-78 and 50ish RH
Age: 45 days from sprout and a few weeks into flower
Light: TS-1000 currently at 18 inches @ 85% power
Amendments: Gaia Green 1tbsp each of 444 and 284 about 4 weeks ago (right before pre-flower), sprinkled some WC and Kelp. Currently giving 3 cups of water every other day at 6.5ph. Seeing some sign's of overwatering so letting her dry out some to deal with a few gnats too.
Problem: She's happy for the most part with some good frost development, just not fatting up yet but will be soon. There is some clawing indicating too much nutes but haven't been amended since day 17 and will continue to water only for the foreseeable future. The yellowing tip is starting to turn brown but has been spreading to the serrated edges. This is only found on a few of the leaves up towards the top of the buds. Lower leaves don't seem to be effected. This is a 9 week strain (give or take) so there's only a few more weeks to go.

 

[Mañ'O'Green]

Looks like too much Phosphorous.

 

[Duceduck]

Looks like too much Phosphorous.

looking at the issues and searching for content on the problem, not once did it even cross my mind that it may have been a P excess.. I'm searching now but surely opens things up a bit. Thanks MOG!
There's 3 plants all different phenos, this one seems to be doing the worst.

 

[Mañ'O'Green]

looking at the issues and searching for content on the problem, not once did it even cross my mind that it may have been a P excess.. I'm searching now but surely opens things up a bit. Thanks MOG!
There's 3 plants all different phenos, this one seems to be doing the worst.

Ooops I meant to say Potassium - Sorry. Every plant is different.

 

[Duceduck]

Ooops I meant to say Potassium - Sorry. Every plant is different.

Update: Did a slurry test this morning 1 part soil and 2 part distilled water. Scraped through the first inch and got some soil below that. The PPM read 260's and ph at 6.6. Doesn't seem too bad but am using Gaia Green and seeing some micronutrients being blocked. Seems to be progressing a little more each day but haven't been feeding anything and only watering every few days of 3-4 cups at 6.5ph. Seems to be like MOG mentioned with an excess of P and maybe K. Hopefully, she can pull through as she just hit the beginning of week 8.

 

[Mañ'O'Green]

Ok so now she is showing signs of magnesium lock also. This would continue to indicate too much Calcium. What is the source and PPM of your starting water.

I think your troubles started by adding Dolomite lime to the HF soil. It already comes with enough for the entire grow. If your tap water is high in calcium it just compounds the problem.

 

[Duceduck]

View attachment 1333532

Ok so now she is showing signs of magnesium lock also. This would continue to indicate too much Calcium. What is the source and PPM of your starting water.

I think your troubles started by adding Dolomite lime to the HF soil. It already comes with enough for the entire grow. If your tap water is high in calcium it just compounds the problem.

Last time I checked, the tap water PPM is in the 60's but no report on what's in it. I haven't been adding any cal-mag but the dolomite lime to start does makes sense. Of the 3, she's the only one with these severe symptoms. Will flushing the medium at this point help to remediate? I did scrape off the top layer of soil and added a new inch or so of HF. Just wanted to try to remove the last amended from a few weeks ago.

 

[Mañ'O'Green]

Last time I checked, the tap water PPM is in the 60's but no report on what's in it. I haven't been adding any cal-mag but the dolomite lime to start does makes sense. Of the 3, she's the only one with these severe symptoms. Will flushing the medium at this point help to remediate? I did scrape off the top layer of soil and added a new inch or so of HF. Just wanted to try to remove the last amended from a few weeks ago.

Flushing HF and OF have not done well for peeps here so I don't recommend doing it. You may have added fresh nutrients with the top dress you probably don't need. We can only guess at what might be in that pot? Soil is not like hydro, you do not remediate anything. You slowly steer it where it needs to go. Autos do not do slow! So growing Autos in soil that lost its balance takes longer to fix than the plant will give it.

It is not all bad news. I have seen very sick looking plants finish with a more than expected crop. These plants are very hardy and if given a chance they will mature. I highly recommend giving it a week of LITFA Make sure your environment is in parameters and water when indicated.

Tag me with pics in a week.