Leaves Curling Under And Wilting But Not Under-watering? Plus Interveinal Necrosis?

[Feetwet]

A couple plants leaves are curling under, two plants are wilted, and one plant has some interveinal necrosis. I put them outside a week ago and fed them 650 ppm (incl 200ppm from the water) Grower's Secret 5-2-1 fish emulsion. That was the first real feed, as I had only given them 1/4 str a week before. Fast forward to three days ago i saw one was wilted and the soil was dry so I watered them all. Added BTi (microbelift) for fungus gnats, added vinegar to correct water to ph of ~6 give or take 0.5, to correct 7.1 soil ph. The next day she's still wilted, and some other plants aren't wilted but have curled under leaves. One has interveinal necrosis. Check the photos.



1. Are you growing from seed or clones? Seed
2. How old are your plants? 4 weeks from planting the germinated seeds
3. How tall are your plants? 8-12in
4. What size containers are they planted in? 1 gal
5. What is your soil mix? Vermisoil Potting Soil
6. How often do you water and what type of water do you use? Every other day. Sun dries them out fairly quick.
7. What is the pH of your water? 8 but I added vinegar until it was from 5.5-6.5 to correct soil ph which was a little high at 7.1
8. What kind of fertilizer do you use and what is its NPK ratio? Three days ago I fed at 650ppm 5-2-1 growers secret (fish emulsion). The water is 200ppm. No chlorine.
9. Do you foliar feed or spray your plants with anything? Not recently.
10. What kind of lights do you use and how many watts combined? (HPS, MH, fluorescent, halogen, incandescent "plant lights") The big bulb in the sky. They went out a little less than a week ago after being hardened off.
11. How close are your lights to the plants?
12. What size is your grow space in square feet?
13. What is the temperature and humidity in your grow space? It's hot out. 87f.
14. What is the pH of the soil? ~7.1 but reducing it
15. Have you noticed any insect activity in your grow space? Fungus gnats. Nematodes applied a week ago, BTi applied two days ago.
16. How much experience do you have growing? None

 

[G gnome]

If its root bound that could be it.

 

[Seamaiden]

I'm sitting here looking at those plants and thinking, "They look HOT." Then, you post this.

13. What is the temperature and humidity in your grow space? It's hot out. 87f.

That is your problem right there. And, in fact, many plants will yellow out and drop leaves when it's too hot. The response is often to feed them. This can often be the worst thing you can do.

You MUST cool the roots off, ASAP. Do not use water to cool. Wrap the pots in white paper or plastic, shade the pots, do whatever you can to mitigate the effects of hot sun on a black pot.

 

[Feetwet]

If its root bound that could be it.

Yea they are in one gal pots... I'm gonna research that.

I'm sitting here looking at those plants and thinking, "They look HOT."

They are definitely hot. The soil even at the bottom is 94f. I'm baking the roots... BUT the thing is, a friend did the same thing last year in the same conditions with no trouble. I'm going to follow your suggestions anyway because they'll do better without all that heat.

 

[Feetwet]

I'm sitting here looking at those plants and thinking, "They look HOT." Then, you post this.

That is your problem right there. And, in fact, many plants will yellow out and drop leaves when it's too hot. The response is often to feed them. This can often be the worst thing you can do.

You MUST cool the roots off, ASAP. Do not use water to cool. Wrap the pots in white paper or plastic, shade the pots, do whatever you can to mitigate the effects of hot sun on a black pot.

So I'm thinking that since they aren't all wilted, maybe because that wilted one's pot really dried out that the roots got really hot AND dry, while the others pots were less dry, so they suffered less and so are less wilted.

I'm going to cover the soil surface with light colored mulch to keep the soil cool and prevent moisture loss, as well as cover the pots with white paint or paper.

 

[showmegreen]

Yep I'm with that "Fair and ever knowledgable" @Seamaiden . toasten'em. Put a tent over'em made outta black screen. If ya don't cookem first they will aclimate.

 

[Quagmire]

Give them some Epsom salt.. looks like magnesium and calcium deficiency to me.. some strains can handle heat quite well.. but I'd say your problem is calmag bro.. give it a try.

Read this and see what you think
In gardening and other agriculture, magnesium sulfate-(Epsom Salt) is used to correct a magnesium or sulfur deficiency in soil; magnesium is an essential element in the chlorophyll molecule, and sulfur is another important micronutrient. It is most commonly applied to potted plants, or to magnesium-hungry crops, such as potatoes, roses, tomatoes, (LOL) lemon trees, peppers and cannabis. The advantage of magnesium sulfate over other magnesium soil amendments (such as dolomitic lime) is its high solubility, which also allows the option of foliar feeding. Solutions of magnesium sulfate are also nearly neutral, as compared to alkaline salts of magnesium, as found in limestone; therefore the use of magnesium sulfate as a magnesium source for soil does not significantly change the soil pH...

Hope this helps.. and try to get your temps down a bit if you can.. I run my room at 78-82 with great results.. some strains like it, but most indica's do just fine.

 

[Seamaiden]

I really have to recommend against this until after he's got those roots cooled down. I've got experience doing this to plants that were clearly heat-stressed and it's very easy to kill them off by trying to feed anything at this point. I hate contradicting someone I respect and admire, but I honestly think that until they're cooled off it's a mistake.

 

[Feetwet]

Give them some Epsom salt.. looks like magnesium and calcium deficiency to me.. some strains can handle heat quite well.. but I'd say your problem is calmag bro.. give it a try.

I think you're correct, as well. Growers Secret has no micros. I'm going to feed very lightly (maybe foliar?) with cal/mag/sulfur and put the unhappy few in a shadier place.

I really have to recommend against this until after he's got those roots cooled down. I've got experience doing this to plants that were clearly heat-stressed and it's very easy to kill them off by trying to feed anything at this point. I hate contradicting someone I respect and admire, but I honestly think that until they're cooled off it's a mistake.

I covered the pots with white paper and mulched with straw but the temps are still high-- 94f. I need to shade the pots but I'm not sure how. Maybe line them up and lean some breathable opaque material against the rims? Most of them are doing fine even with those temps! Wish I could cool them down, though. I heard a little clay in the soil helps.

 

[rubthe nub]

here's an old trick that will typically cure that problem

Heeling in (google for an in depth explanation)

I've found a pile of mulch often works as well as a pile of soil

Good Luck

 

[Quagmire]

94f is incredibly high, wonder what color your root base is? sucks, I deal with high temps in my grow room to bro and I manage to keep mine at 82f or lower. Just bought a better intake fan and enlarged my passive hole from 4" to 6" and things improved fast. Moving my window a/c unit to the office so it will cool the room down that the passive air is being drawn in from..
But man that's awfully hot and Seamaiden is right, should be your #1 issue to face first.. just thought I saw some calmag issues and wasn't recommending that exact product but thought they had a good write up on what a good Epsom salt will do for ya down the road.. but yeah, one thing at a time.
Not sure I'd do any leaf spraying either until you get your temps down either.. may just make matters worse.. wish you the best and sorry if I misled ya in any way bro..

 

[Quagmire]

Hey, what is that you have them sitting on?? just wondering if it's heating up your plants base thru the day.. just went and looked at your photo again and was thinking, how hot is that getting and is that your biggest culprit is all. man I hope ya get this figured.. luck

 

[rubthe nub]

Transplant ASAP
those tiny little pots ain't doing you any favors right now.
If you cant transplant, I'd get 'em heeled in ASAP
Good Luck

 

[Feetwet]

Thanks for the help everyone. The new growth is looking great but some of those lower fan leaves are still sad and wilty and some died. I think it's the hot container but I can't do much right now since I'm still looking for property here in NorCal. Getting late :( Just can't swing so much cash upfront.

Supposed to get really hot next week, too. I can't wait to get them in pots. I'm going to shade cloth them.

 

[Apollo13]

I use the 16 inch double mylar bubble wrap on my uc buckets. It works great and cheap. It is less than 20 bucks for 25 foot. Blocks light aND insulates. The bigger the pot the better. Also get them on the ground if possible or concrete. Lift ur light up if possible and just in case, water with just water and 50 ppm cal mag. As a rule of thumb, don't add when plant roots are hurt or weak. When hot environment, usually drop the nutrients. Rather have them starve then burn and not enough light than too much. My 2 cents. Good luck with the heat... another thing I do is shut light off for hour 5-6 or if really hot, sometimes hour 3-4 and again at 7-8. I guess I'd rather only run a few hours of light over 12 hours than kill them. No roots and why bother flower?

 

[Seamaiden]

This is outdoors. He can't really lift the light, or shut it off. ;)

 

[xavier7995]

Strain selection seems like it would be very important in your situation....but to late for that now:) Stuff grows great in the tropics, but it has to be a strain acclimated to that environment.
Kind of labor intensive, but you could try bringing them indoors during the hottest parts of the days. Repotting to larger pot would also help since it would give more buffer before the rootzone got that hot.

It does look like a calmag issue (maybe K as well) based on the leaves, but improper PH and and temp can prevent the plant from absorbing what is there properly so concurred that it would be a good plan to get that stuff sorted first before looking at adjusting nutes much.