Leaves curling up, getting yellow/brown!

Hey guys.

It's my second try, and my second plant.

My other died of similar stuff to this one. It's just a seedling, making 2 weeks old today(since germinating). I'm also growing another plant for a friend, and she has been passing through the same(on smaller leaves) Here are the pics :



Some info:

Soil : sunshine mix #6, perlite, worm castings ; soil has been moist for some time now
Light : two 45W CFL, brand OurLux
Ventilation : none
PH : no measure, but i'm using water with 6.8 pH
Nutes : used 2 times since the problems started showing, FloraNova Grow(used 1/2 of recommended by LucasFormula)
Humidity and Temperature : temperature is around 68 farenheit, and humidity is 60%-90%(city levels) - I let my cabinet open some times for new air to come in

What has been done so far from the start of the problem

1 - I raised the lights 3". Must have been wednesday.
2 - I put some nutes in my water, and watered it twice(2 days interval). No changes.
3 - I changed the GROWING CABINET yesterday night. So far no changes.

It's just a seedling, so I can't believe its nutes. Must be pH? Over-watering?

Looks like maybe salt burn. Some soils will have more mineral salts or salt residue than others.

you don't need to feed seedlings in a pre fertilized soil

Imo its getting to much nutes im pretty sure the should spend there first 2-3 week without nutes.

My diagnosis is you are trying too hard. Just water it and leave it alone for a couple weeks. I know you want to care for it every step of the way, but cannabis is the opposite of a person. They need almost nothing when first starting out life and get needier as life goes on.

-Sap

Ogracious said:

My diagnosis is you are trying too hard. Just water it and leave it alone for a couple weeks. I know you want to care for it every step of the way, but cannabis is the opposite of a person. They need almost nothing when first starting out life and get needier as life goes on.

-Sap

Click to expand...

That's a nice advice, really! But if it's dying you need to fix it... it happened before and the plant died, thats why i'm so anxious

I just started nuting it AFTER the leaves started turning brown!

Looks to me like a combo of lights being to close and too much food. NO nutes in that soil for 3 weeks, and then at 1/4 strength, slowly building up. Just use water. Keep the lights back and no food, and it looks like they will recover. Get a PPM tester so you take the guess work out of how much you are feeding them, that and a PH tester are a must if you want to grow seriously. Peace

weedizard said:

That's a nice advice, really! But if it's dying you need to fix it... it happened before and the plant died, thats why i'm so anxious

I just started nuting it AFTER the leaves started turning brown!

Click to expand...

Yes, I wasn't saying I wouldn't have added the nutes initially, just that I would leave it alone now. Those leaves look like either nute or light burn. My money is on the light being too close, ESPECIALLY with no ventilation. Plants naturally cool themselves by evaporating water from their leaves, which happens very slowly without airflow. I would keep a very close eye on it's growth to make sure it doesn't get too close. Any reason you cannot add a fan? Money?

-Sap

Ogracious said:

Yes, I wasn't saying I wouldn't have added the nutes initially, just that I would leave it alone now. Those leaves look like either nute or light burn. My money is on the light being too close, ESPECIALLY with no ventilation. Plants naturally cool themselves by evaporating water from their leaves, which happens very slowly without airflow. I would keep a very close eye on it's growth to make sure it doesn't get too close. Any reason you cannot add a fan? Money?

-Sap

Click to expand...

I can add a fan, but can I keep my closet closed if I add it?

here are some pics of my closet... I tought CFL's were good because they didnt need fans.

When the heat gets too high, the edges of the serrated leaves will begin to curl up even if there are no burns or other signs of light stress.

Find a way to lower the temperature and/or increase the circulation in the grow room or grow area if heat is the problem. Having a small fan blowing over the tops of your plants will help prevent hot spots from forming directly under your grow lights. If your marijuana plants are just getting too much light, try removing some of the lights or moving your lights further away from the tops of the plants. ! Good Luck !!

lets just say this. I do a hydroponic (inert medium with no nutrients) grow and use tap water on my seedlings and they grow fine. My ppm is 110 out of the tap which is very low, after a while i work into 1/8 dose , then up to 1/4 slowly, and so on.

worm castings and sunshine mix are both microbe friendly, if i were you just a tid-bit of castings at first mixed into the sunshine mix (actually check and see , it may actually already have castings in it...)
your lights may be too close to the pots and heating up the root zone, leading to either an over-dried medium or a medium thats warm and wet, causing anaerobic bacteria (mostly all bad bacteria, that thrives in lack of oxygen environment) to rot your root.

adding the nutrient may be killing any of the benificials that are in there.

my suggestion is insulate your little pots next time, or plant them into something bigger.
I went as far as getting bubble wrap insulation, doing one layer on the outside of the pot (bottom not insulated) and making a "cap" with a slot for the stem sort of like a pac-man, and like 5 or 6 holes to allow the soil to breathe.

i used a soil thermometer before and after, the root temps went from 76-77 in the day and a few degrees cooler at night, down to 73 at all times. When I water now, the water sort of governs the root temp more because the soil doesn't get affected by the heat from the t5's.

Once the canopy gets larger, the soil zone temperature will go down more and more, because it will be shaded. The cap i made is also reflecting more light, and prevents algae growth!!

optimal rootzone temps IMO are 70 tops at day, and 60 lowest at night. The temperature change is GOOD for them , know that little factors such as this will change your grow dramatically.

chairroller said:

When the heat gets too high, the edges of the serrated leaves will begin to curl up even if there are no burns or other signs of light stress.

Find a way to lower the temperature and/or increase the circulation in the grow room or grow area if heat is the problem. Having a small fan blowing over the tops of your plants will help prevent hot spots from forming directly under your grow lights. If your marijuana plants are just getting too much light, try removing some of the lights or moving your lights further away from the tops of the plants. ! Good Luck !!

Click to expand...

Thanks man! Looks like i'm gonna add a fan...
but would a fan work even if i keep my closet door closed??

you need a hole at the bottom of it, for air to go into, and then a fan up top that pushes air out. the fan up top will pull cool air from the floor hole up through the root area then up through your canopy and then finally cool off your lights and recirulate back into your room.

then you also need a small oscillating fan or a small fan or 2 pointed at the wall (direct fan all the time is really bad) to help strengthen the stems by making them sway around (also shakes canopy a little and allows light to the bottom)

weedizard said:

Thanks man! Looks like i'm gonna add a fan...
but would a fan work even if i keep my closet door closed??

Click to expand...

Although it would be optimal to have a hole in the closet door for a fan, circulating the air with the door closed will still cool your plant and is better than not having airflow.

-Sap

Better leave it open ! But there is no problem !!