Need some advice

Relatively new to gardening but have done my homework. This is my second plant that has gone to flower and has seemed to stop dead in its tracks.
All foliage was nice and green until midway through the 3rd week of flowering buds began to develop nicely but stopped prematurely due to major fan leaf loss.
Ph has been kept stable at 6.5 to 7 and even went as far as to not fertalize this second plant anymore when I noticed the problem. My thought is that over the 12/12 cycle things cool off too much for the roots causing the plant to start cannibalizing itself? Soil doesnt have the best drainage as I'm working with what I have available (miracle grow and semi sandy soil) Stems have also started to turn purple which is why I'm thinking its temp/oxygen related.
Started on a 400w MH at 18/6 the switched to a 400 w LED at 12/12. Fertalizers used are Alaska fish fertilizer and Alaska more bloom (both selsomly used on this plant). Same outcome with both plants any help or advice is appreciated.

Out of curiosity what was the average temperature and humidity? For light off and on

You've gotta feed em!

Miracle gro soil is not recommended but you should be able to make it work.

How did you measure PH?
Alaska fish fertilizers have a very low PH.

Light on temp was at 75 for veg and LED could only get to 70 for flowering. Not sure but around 50% humidity (basement) light off could have been closer to low 60's with winter on it's way. First plant seemed to develop more and I think it was due to warmer overnight temps (first plant flowered in spring second is flowering in winter)

Chunky Stool said:

You've gotta feed em!

Miracle gro soil is not recommended but you should be able to make it work.

How did you measure PH?
Alaska fish fertilizers have a very low PH.

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On next to no budget so all I have is a probe ph tester at the moment. Would feed and let the ph balance out through the next waterings.
Was told to dial back feed minimaly when caring for a feminized autoflower is this correct?
Recommendations for an inexpensive/reliable ph/ppm meter?

Lone_strainger said:

On next to no budget so all I have is a probe ph tester at the moment. Would feed and let the ph balance out through the next waterings.
Was told to dial back feed minimaly when caring for a feminized autoflower is this correct?
Recommendations for an inexpensive/reliable ph/ppm meter?

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I buy cheap ph & ppm meters off amazon and just replace them every year -- but they are for checking liquids.
The best soil check is the one that requires you to mix a slurry using distilled water, strain it through a coffee filter, add a capsule of magic powder, then check a color chart.
It's going to be hard to dial up the nutes using alaska fish fertilizer unless you have some PH up. Liquid silica works great for raising PH -- and it helps your plants.
-- edit --
I've never grown autos so I can't help with a feeding schedule for them.

Chunky Stool said:

I buy cheap ph & ppm meters off amazon and just replace them every year -- but they are for checking liquids.
The best soil check is the one that requires you to mix a slurry using distilled water, strain it through a coffee filter, add a capsule of magic powder, then check a color chart.
It's going to be hard to dial up the nutes using alaska fish fertilizer unless you have some PH up. Liquid silica works great for raising PH -- and it helps your plants.
-- edit --
I've never grown autos so I can't help with a feeding schedule for them.

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K makes sense I feel slightly foolish but in my defense i did nute burn right away lol. Is this plant worth any effort anymore or should I cut my losses?

Lone_strainger said:

K makes sense I feel slightly foolish but in my defense i did nute burn right away lol. Is this plant worth any effort anymore or should I cut my losses?

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I would definitely finish her but you will get better results with plants that are well fed w/no deficiencies.
You will learn how to read your plants; all it takes is practice.
Hell I still screw up.
I've got seedlings right now that are showing serious mag def -- and it's totally my fault.

Lone_strainger said:

Was told to dial back feed minimaly when caring for a feminized autoflower is this correct?

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Are you growing autoflowers? You're not supposed to flip lights to 12/12 with autoflowers.

autoflowers are a 18/6 plant no need to flip to 12/12.
Temps are too cold
Soil sucks poor drainage
autoflowers are light feeders I believe

I think if you burnt up your plant you would see more of the burnt leaves like in the first pic on more of the plant so I just think you have root issues from the poor soil drainage and the cold temps are not helping at all. temps could be 85 during the day and no lower than 72 at the night time imo

so basically you already have it figured out. If you had a heat matt like for cuttings and some insulation to wrap around the pot to keep the heat in would help some a beach towel could work instead of insulation. a meat thermometer stuck inside the pot maybe 2/3 down stuck in the side of the pot could help to know what the temps of your roots are maybe idk. Keep the roots warmer and the plant wont mind the colder temps as much but cold roots it will slow it down alot. next time in veg up the nitrogen a little if you keep using the same nutes like you have been.

Need magnesium.

Bout a pound ......










*sorry .... somebody dared me

Budzbuddha said:

Bout a pound ......










*sorry .... somebody dared me

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ouch

Cold cellars are great for DWC but not so great for soil grows. My garden soil is great but if I put some in a bucket and try to grow weed it never works well. You have to buy either good soil or Pro Mix. I think you need to switch to DWC and order some hydro nutes.

Thanks for the tips good to know it's nothing major. Had to flip lights due to height restraints... blew my mind how fast I ran out of ceiling space. Hope to pass recreational in my home state today wish us luck.