Can't figure it out.

Hey everyone,

So I can't figure out what I'm doing wrong. This is not my first time growing and I do know what I'm doing wrong this time around. So here is the info...

Soil: Promix HP
Water Ph: 6.5
Light: HLG65 @ 22" above.
Temperature: 24C
Humidity: 65%
Intake and exhaust fans. With carbon filter.
2 isolating fans.
Everything is automated to keep optimal.
Strain: Blueberry Cupcake - HSC
Started from seed July.

I add kelp every other water. Ph to 6.5
I don't think I'm over watering or under but I could be wrong. Doubt it. I would think a feed but I ran 4 before these new 4 and I had the same issue happening so I gave them a half feed and it burned them to death. So these are the new 4 I started and it's happening again. It looks like overfeeding or under feeding. Also looks like a N deficiency. What the heck am I doing wrong?

I also added a picture of the kelp I use. I wonder if that's what's causing it. Used it for years before. It says it's a 20:1 and that's 200ml to a gallon. I only use 1 tablespoon per gallon. So I can't see it burning them.

Any and all comments are greatly appreciated. Thanks in advance.

BurnzyBurnz said:

Hey everyone,

So I can't figure out what I'm doing wrong. This is not my first time growing and I do know what I'm doing wrong this time around. So here is the info...

Soil: Promix HP
Water Ph: 6.5
Light: HLG65 @ 22" above.
Temperature: 24C
Humidity: 65%
Intake and exhaust fans. With carbon filter.
2 isolating fans.
Everything is automated to keep optimal.
Strain: Blueberry Cupcake - HSC
Started from seed July.

I add kelp every other water. Ph to 6.5
I don't think I'm over watering or under but I could be wrong. Doubt it. I would think a feed but I ran 4 before these new 4 and I had the same issue happening so I gave them a half feed and it burned them to death. So these are the new 4 I started and it's happening again. It looks like overfeeding or under feeding. Also looks like a N deficiency. What the heck am I doing wrong?

Any and all comments are greatly appreciated. Thanks in advance.

Click to expand...

At a glance the Pro mix looks really crusty, and I think I see some green algae on top, so 1st thought is way over watered.

I think 6.5ph is too high for ProMix HP. Most suggest 5.8-6.3pH. And I agree with the notion that there's a watering issue. I use ProMix HP and it never gets that green and swampy looking.

Not sure about your feed...they look like they're hungry to me, but also you've obviously cooked them at some point too. I don't know the ins and outs of just feeding kelp for nutrients.

my guess is too much water. It generally creates symptoms similar to N deficiency

steve870 said:

my guess is too much water. It generally creates symptoms similar to N deficiency

Click to expand...

What's to much water ? I wait for a little run off and stop. Probably like 125ml of water only.

I also grow in ProMix HP, it is ph buffered so no need to ph your water.

But it does not not contain any nutrients and Kelp is only a supplement, not a full feed fertilizer.

And it appears that one pot is sitting in water ?

I let my ProMix dry out almost completely before feeding again. At this stage I would not be giving a full watering.

And I use plant elevators and saucers to keep the pot out of the run off.

My goal to give no more than the plant can use in three to four days.

Cheers

chuckeye said:

I also grow in ProMix HP, it is ph buffered so no need to ph your water.

But it does not not contain any nutrients and Kelp is only a supplement, not a full feed fertilizer.

And it appears that one pot is sitting in water ?

I let my ProMix dry out almost completely before feeding again. At this stage I would not be giving a full watering.

My goal to give no more than the plant can use in three to four days.

Cheers

Click to expand...

Yep. My ProMix experience is that once I've watered thoroughly to a good amount of runoff, I'm roughly at 4ish days before needing to re-water.

BurnzyBurnz said:

What's to much water ? I wait for a little run off and stop. Probably like 125ml of water only.

Click to expand...

let dry almost completely before watering. Runoff isn't necessary if you are not feeding.so you can gauge an amount of water per day and water every day just the amount your plant needs

LeastExpectedGrower said:

Yep. My ProMix experience is that once I've watered thoroughly to a good amount of runoff, I'm roughly at 4ish days before needing to re-water.

Click to expand...

Pretty much what I've been doing and ended up here.

chuckeye said:

I also grow in ProMix HP, it is ph buffered so no need to ph your water.

But it does not not contain any nutrients and Kelp is only a supplement, not a full feed fertilizer.

And it appears that one pot is sitting in water ?

I let my ProMix dry out almost completely before feeding again. At this stage I would not be giving a full watering.

And I use plant elevators and saucers to keep the pot out of the run off.

My goal to give no more than the plant can use in three to four days.

Cheers

Click to expand...

So just to be clear ... Your suggestion is I let it dry out and feed it? I have foxfarm veg 6-4-4. But they look burned or that they are eating them selves to stay alive, I can't tell. I wonder if it's the kelp I'm using... It's called marphyl. I wonder if it's making the soil hot.

It's weird. I had this problem 2 grows ago. Turned out the plants needed to be transplanted into grow bags. I'll never use pots again. The pots stayed wet at the roots, the center of the pots was very wet when I did this. The rest of the pot was very dry. Also you probably already know your plants can only handle 1/2 dose nutrients at this stage and only every other watering. Looks like possible lock out so I wouldn't give them any nutes till its fixed. The nutes you have in the soil are probably built up due to the lockout.
Just trying to help.

LeastExpectedGrower said:

Yep. My ProMix experience is that once I've watered thoroughly to a good amount of runoff, I'm roughly at 4ish days before needing to re-water.

Click to expand...

Ya it doesn't drain well. Things domino.

BurnzyBurnz said:

So just to be clear ... Your suggestion is I let it dry out and feed it? I have foxfarm veg 6-4-4. But they look burned or that they are eating them selves to stay alive, I can't tell. I wonder if it's the kelp I'm using... It's called marphyl. I wonder if it's making the soil hot.

Click to expand...

it depends are you feeding them already? The thing with promix is that you can treat it as hydro or soil. in a hydro setup you rise EC to diminish water uptake by the plant. in soil you let it dry out more and water less.

BurnzyBurnz said:

Pretty much what I've been doing and ended up here.

Click to expand...

Your Promix at roughly the same time in the grow looks really different from how mine looks. This is a picture just after a plant has been watered:

Mechman60 said:

Ya it doesn't drain well. Things domino.

Click to expand...

I dunno. It's been fine for me and I like the 3-4 day watering window. I start in smaller 3/4 gallon pots then once the plants' leaves start to about reach the perimeter of the pot I transplant into 5g bags of promix. I alternate water/feed and wait until they're dry between.

BurnzyBurnz said:

So just to be clear ... Your suggestion is I let it dry out and feed it? I have foxfarm veg 6-4-4. But they look burned or that they are eating them selves to stay alive, I can't tell. I wonder if it's the kelp I'm using... It's called marphyl. I wonder if it's making the soil hot.

Click to expand...

Yes, dry before water and a light feed.

Right now I would do a flush with 3X water, 2X with just water and on the last add some food. And flush that kelp in the toilet

Grow bags work well and they are cheap

At the least, I would drill at least a half dozen 1/4" holes in the bottom of your pots AND a couple of rows up the sides from the bottom.

ProMix drains really well in a proper pot and will only hold so much water. If you water correctly you shouldn't have any issues.

Cheers

LeastExpectedGrower said:

I dunno. It's been fine for me and I like the 3-4 day watering window. I start in smaller 3/4 gallon pots then once the plants' leaves start to about reach the perimeter of the pot I transplant into 5g bags of promix. I alternate water/feed and wait until they're dry between.

Click to expand...

Grow bag are pretty forgiving. And 5 gal. Is my choice also. I mix my own soil tho. Some folks can't resist watering too much.
I've no experience with any pre mixes tho. That's your expertise. Hope you can help with that.

chuckeye said:

Yes, dry before water and a light feed.

Right now I would do a flush with 3X water, 2X with just water and on the last add some food. And flush that kelp in the toilet

Grow bags work well and they are cheap

At the least, I would drill at least a half dozen 1/4" holes in the bottom of your pots AND a couple of rows up the sides from the bottom.

ProMix drains really well in a proper pot and will only hold so much water. If you water correctly you shouldn't have any issues.

Cheers

Click to expand...

Something like this.

Mechman60 said:

Grow bag are pretty forgiving. And 5 gal. Is my choice also. I mix my own soil tho. Some folks can't resist watering too much.
I've no experience with any pre mixes tho. That's your expertise. Hope you can help with that.

Click to expand...

The only time Promix was wonky on me was while using blumats, which are a non-runoff constant drip and my issues ended up never being the actual watering or water content, but handling the feeding portion effectively. When I hand-water there's no real issues. Though the OP should consider looking up some details on the hows and whys of Promix HP, which is generally considered a 'soilless medium,' if he hasn't already.

Mechman60 said:

Something like this.

Click to expand...

Patients is a virtue during all this.