Heat Stress?

[justin21]

I just bought a new 400w HPS system a few days ago and set it up with a reflector in my 2 foot wide by 5 foot long closet with 3 plants that i had growing under 5 fleorecents.

I put the new light about 16" away at first, one fan inside blowing at the plants (14" round inside closet) and it was blowing in between the light and the plant tops, the whole plants are moving.

I also have one fan that is 20" long by 10" wide in the left door blowing air in, and then i open the right door to let air out.

The thing is, this is in my bedroom. So at night I would take the door fan out, and close both doors(mostly cause of the door fan being loud, and light)...I dont have a thermoter but heat didnt seem too too bad(i think)..

for the first day and a half or 2 days, the plants were fine when i did this.

This morning i woke up to check and there were spots over the tops, afew lower leaves but way less spots on those. 2 plants were affected of the 3, the least affected was the one that had the most wind blown at it.

i took some pics, arnt the best but you can somewhat see the leafs and spots.

I'm wondering what did this, heat or light or possibly lack of air.

The closet is made of sliding doors with about half inch cracks all around so its not tightly sealed but might be lack of air + heat.

Just wondering what you guys think, this is my first setup so i'm still learning and dont want to screw this up.


Thanks!

 

[bran1981]

You need to find out how hot it is it there. By looking at the pics, it looks like your leaves are also curling up on the edges witch means your burning them with to much nutes. It's hard to really see the pics.

 

[captain792000]

the key is to get a thermometer asap man..... heat has to be a major issue here....

 

[Little Tommy]

If that is not an air cooled light it may be too close. It also has the look of being wind burned. This can happen if the fans are blowing too hard & directly on the plants. The plants should be moving very gently swaying back and forth. If you are moving branches around with the breeze from the fan it is too close or too hard. A 400 watt light that is not air cooled should be about 16" away from the tallest top with proper ventilation. You do need to get a thermometer to see where your temps are. A 400 watt light will generate lots of heat in a confined space like that. 75F is the happy zone for temps and you should try to avoid any difference more than 10F between lights on & off.

 

[smallclosetgrowr]

as much as it might sound like its heat stress imo im not seeing any signs of it tho , spots aint really related to heat stress.

 

[justin21]

as much as it might sound like its heat stress imo im not seeing any signs of it tho , spots aint really related to heat stress.

I will get a thermometer soon, but ummm might, the leaves are a bit screwed so might be wind cause the wind is very direct.

I dont know cause these spots appeared in 6 hours time while i was sleeping while the doors were closed and sealed with 1 fan running inside.

Since it didnt spread, kept the doors open more.

Leaves still seem a bit stressed on top.

 

[AquafinaOrbit]

as much as it might sound like its heat stress imo im not seeing any signs of it tho , spots aint really related to heat stress.

I agree. Only way heat causes something like that is if you foliar feed and the HID heats up the water till it burns your leaves. Edges curling up as said is a main sign, but side edges also curl up under windburn.

 

[justin21]

oh btw i aint putting any nutes right now. Just put some once when they were starting to give them a boost. been a month already since.

 

[AquafinaOrbit]

They should be getting nutes by now then. Mainly Nitrogen which has a large effect on the color of a plant.

 

[justin21]

They should be getting nutes by now then. Mainly Nitrogen which has a large effect on the color of a plant.

yes i will start giving it.(all i got right now is miracle grow multi purpose 24-8-16 or something But, i'm pretty sure the curling is the wind now, but the spots that happened was?

(cant be nutes)

 

[justin21]

yes i will start giving it.(all i got right now is miracle grow multi purpose 24-8-16 or something But, i'm pretty sure the curling is the wind now, but the spots that happened was?

(cant be nutes)

more pics.

Pic6 is the spots i was saying on one leaf of the plant, pretty much only leaf that was affected.

pic7 seems to be something else, wind burn or whatever, new growth seems very slow now on top of plant only, the rest grows fine.

Leafs on top seem different and pointy.

 

[MR.Budder]

if u splash water on top of the leaves when they are under alot of heat it will cause spots

 

[justin21]

if u splash water on top of the leaves when they are under alot of heat it will cause spots

I didn't splash any water.

I just took 2 more pics.

1 pic is yellow on the tip of some leaves, i took a pic of 1 leaf as an example.

the other picture is the top leaf, most of the leaves look like this now so its weird, very unhealthy, plants are not growing anymore, new growth leaves are like the ones in the pic i just took.

in picture 8, you can see one new growth leaf lower left, it also has yellow tips and is very slim, the leaves are not flat open.


i need help!! its getting worse and i dont know what to do.

 

[Natures Cure]

more pics.

Pic6 is the spots i was saying on one leaf of the plant, pretty much only leaf that was affected.

pic7 seems to be something else, wind burn or whatever, new growth seems very slow now on top of plant only, the rest grows fine.

Leafs on top seem different and pointy.

Resolution . . . ahhhh . . . not so good.

what's your RH?

 

[justin21]

Resolution . . . ahhhh . . . not so good.

what's your RH?

I know, resolution sucks.. all i can do for now and i dont know RH...

 

[drew k.420]

pics arent really good enough to tell .do you test the PH of your water before feeding.could be the beginning of PH spotting,i cant really tell from those poor resolution pictures ...it looks like it could be 10 different things,but until you get better pics youll get all 10 of those!!!good luck

 

[Pipe Dream]

+Those closets can be a pain in the ass I know my first crop was in on. I think maybe that light is too much in such a small area. Personally I used a 175 watt and had no issues other than stretching. You can use the 400 but your going to need to figure out a way to provide fresh air, get rid of the heat and keep the light out. Mine went hermie on me I think because of light leaks.

The first picture above with the yellow looks to be nitrogen defficiency the MG in the soil has probably been used up.

 

[justin21]

+Those closets can be a pain in the ass I know my first crop was in on. I think maybe that light is too much in such a small area. Personally I used a 175 watt and had no issues other than stretching. You can use the 400 but your going to need to figure out a way to provide fresh air, get rid of the heat and keep the light out. Mine went hermie on me I think because of light leaks.

The first picture above with the yellow looks to be nitrogen defficiency the MG in the soil has probably been used up.

oh. ic.. and no i havnt been testing ph, i need to get a kit..

I know that a lot of the leaves that are from the top half of the 3 plants look like in the book "marijuana horticolture medical grower's bible" on page 246 where it says leaf fringe standing up, possible toxic salt buildup, heat stress.

I just said this to show a clear example of what the leaves look like, but now there are some yellow tips on some fresh leaves like i showed on a pic recently in the thread.

 

[Jonus]

Going from fluros to HID lighting will cause that. The plants built their defences against a soft light source that was hitting them with about 1000-2000 lumens per square foot, to then get hit with 5000-8000 lumens per square foot, plus the increase in ambient heat will result in two things, leaf burn from the ambient heat and light shock from the massive increase in lumens.

 

[LIttle Jimmy]

Dude that is for sure heat stress! But more specifically that is what happens when you put plants under an HID light when they were not ready for it COMBINED with heat stress! Plants must be shaded when you first put them under the HID for a couple of days....especially if you vegged them under a fluorescent light

But the leaf curl is just a tiny bit of nute deficiency....The main problem in these pics is the heat/light stress...

I saw that many times in my time of growing....I had a closet just like yours (sliding doors) and until I built a "closet room" I always had heat problems....even with exhaust fans....