First time grower: Possible manganese deficiency, in need of a diagnosis!

[fasttanoy]

Hi guys,

I'm a first time grower and am having problems getting started. I have shiva skunk and jack flash seedlings planted in a coco/perlite 75/25 mix that are currently propagating under a T5 fluorescent light. My progress from the beginning can be found in my journal
In my grow room the temperature ranged from 70-76F and the relative humidity is at a constant 65%

My problem is that the growth of my plants has been virtually non-existent from days 5-11. Today (Day 12) I noticed some brown spots on 4 out of 6 of the plants. My best guess is manganese deficiency but I was hoping someone with more experience could take a look at them:

Edit: Just thought of something important: if it were manganese deficiency would this also explain the lack of growth over the last 6 days?

 

[PeytonManning]

What's your ph? That's usually what causes that kind of lockout

 

[fasttanoy]

What's your ph? That's usually what causes that kind of lockout

pH has usually been 5.8

I wasn't sure though whether the brown dots were a sign of manganese, calcium or iron deficiency so as a test I've now fed plants and adjusted their root pH to 5.5, 6 and 6.5 but as yet still no sign of growth

I also thought the issue could be overwatering so I let one plant go without water for 7 days and that one was no different from the rest

 

[PeytonManning]

I believe coco is notorious for calcium deficiencies. And you can never really have too much calcium

 

[Christine Green]

Now that you've fed them, give them time to recover. They had no nutrients in their soil. What light do you have them under? They don't need much more than a T5 at this stage, or at least keep a LED 2-3 feet away.
I hope that helps!

 

[fasttanoy]

I believe coco is notorious for calcium deficiencies. And you can never really have too much calcium

I heard this too when I researched coco before my grown. In anticipation of this I bought some CalMag and have fed some to one of my plants so if this is the issues hopefully we'll see some growth soon!

Thanks for your time

 

[fasttanoy]

Now that you've fed them, give them time to recover. They had no nutrients in their soil. What light do you have them under? They don't need much more than a T5 at this stage, or at least keep a LED 2-3 feet away.
I hope that helps!

Thanks for the advice, the plan is to just chill out and observe over the next few days. At the moment the tops of the leaves are 4 inches away from the T5

 

[PeytonManning]

Good thinking ahead in that one. I use cal/mag every watering even if I don't need it.

 

[fasttanoy]

What's your ph? That's usually what causes that kind of lockout

I think your two posts combined just caused me to have a revelation! I think I've been too stringent with my pH- I've read that the optimal pH for a hydro grow is 5.8 so I've been ensuring that my plants stay at that level, however I think in doing so I've not allowed my plants to absorb calcium.

Does this sound about right to you? If so is there any way I can adjust the pH in freshly fed plants without overwatering them?

Cheers mate

 

[PeytonManning]

Sounds about right. I let mine fluctuate between 5.8 and 6.2 throughout the week

 

[PeytonManning]

Not sure if you can do it now without over watering. That's why I chose hempy. Passive hydro, impossible to over water so you can flush and do what you need when you need to. Perlite is ph neutral and holds/contains no nutes. Haven't had a single deficiency on my first grow, so I know I'll never change from that. I thought about coco but saw you have to ph it and charge it before use, salt buildup,etc

 

[fasttanoy]

Not sure if you can do it now without over watering. That's why I chose hempy. Passive hydro, impossible to over water so you can flush and do what you need when you need to. Perlite is ph neutral and holds/contains no nutes. Haven't had a single deficiency on my first grow, so I know I'll never change from that. I thought about coco but saw you have to ph it and charge it before use, salt buildup,etc

I'll wait for few days and then bring the pH up to 6.2. Thanks for all your help, I feel a lot better about my chances with the grow now. Any chance you could check out my journal, I imagine you'd be good at picking up on the newbie mistakes I miss!

Just so you know I love Futurama, I've even listened to the DVD commentaries, which are awesome by the way

 

[PeytonManning]

Futurama is my favorite. I've listened to the commentary too! Always nice to hear the genius behind the scenes. I'll go check out your journal and see if anything stands out

 

[shottafire]

They look slightly hungry. I am in my first coco grow and it is going well so far. I know that you never want to feed plain water in coco since it throws off the cation balance in the rootzone. Got to keep the feeds consistent you could feed .5 ec to seedlings and gradually working your way up.

 

[fasttanoy]

Futurama is my favorite. I've listened to the commentary too! Always nice to hear the genius behind the scenes. I'll go check out your journal and see if anything stands out

The only time when a commentary has made me laugh out loud is when in one episode someone asked "are we allowed to ruin what's about to happen in the episode" to which the reply was "we're allowed to do that, we're just not allowed to ruin what's about to happen in the commentary"

 

[PeytonManning]

The first few times I watched them in DVD I always wondered why some episodes had just black screen for five minutes after episode ended. Turned on commentary and realized they love to talk lol. Hoping Futurama comes back soon. Been loving Archer and chozen also. Huge adult swim fan! Venture bros, metalacolypse, frisky dingo. I hate death metal but have all of deathkloks albums and Brendan smalls album