Leaves turning yellow

Armo

Well-known member
I have 6 mature fig trees growing in my 8x4 growtent with 2 x 400w LED lights.
I think its a bit too crowded in there and should only go with 5 trees max next year.

My problem is that bottom leaves are starting to turn yellow, top growth seems fine. They are very close to the lights so I have pinched the buds to buy some time until I take them outside.

I am keeping the humidity around 45-50% with a dehumidifier, tempatures around 21-27C (70-80F) with lights on and off. Watering every other day and I fertilize with N-P-K weekly, giving fish fertilizer every 2-3 weeks and cal-mag every couple of weeks.

I also have two fans in the tent to circulate the air, one above the tree and one in the middle.

What am I doing wrong?
 

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This is a classic case of chlorosis due to lack of light, which is quite common when growing figs in crowded tents. I have experienced that myself.

The solution, which you mentioned yourself, is not to overcrowd. Another solution is to get stronger lights, which will give you a better canopy penetration. For comparison, in my 4x8 tent I run TWO 800W lights.


Another solution - just pick up the fallen leaves and ignore it. The tree will be fine, and the fig production will be fine... as long as the problem doesn't persist for too long and you end up losing most of the canopy.

Here is my Smith from last year, which got barely any light sitting in the corner of my grow tent next to a dehumidifier. It lost most of the bottom leaves... but look at all the figs that hung on and ripened just fine.
figs-577.jpg
 
This is a classic case of chlorosis due to lack of light, which is quite common when growing figs in crowded tents. I have experienced that myself.

The solution, which you mentioned yourself, is not to overcrowd. Another solution is to get stronger lights, which will give you a better canopy penetration. For comparison, in my 4x8 tent I run TWO 800W lights.


Another solution - just pick up the fallen leaves and ignore it. The tree will be fine, and the fig production will be fine... as long as the problem doesn't persist for too long and you end up losing most of the canopy.

Here is my Smith from last year, which got barely any light sitting in the corner of my grow tent next to a dehumidifier. It lost most of the bottom leaves... but look at all the figs that hung on and ripened just fine.
figs-577.jpg
I love my Smith Fig :) Your tree looks amazing.

Light is the biggest problem I think. Mine are not bar style and light doesn't penetrate to the sides too much.
Another problem it might be having is the soil ph level and fertilizer uptake issue. Ive read to water it down too get rid of build up salts.
 
I love my Smith Fig :) Your tree looks amazing.

Light is the biggest problem I think. Mine are not bar style and light doesn't penetrate to the sides too much.
Another problem it might be having is the soil ph level and fertilizer uptake issue. Ive read to water it down too get rid of build up salts.
I assumed pH is in balance as it's easy to check. If you suspect pH issues, the only best thing to do is to check it and then adjust if needed. I would not try to guess here.

If you use only or mostly synthetics, salt build-up is a common issue, which can be taken care of with an occasional flush. It also depends on how you water you plants... if you water until a good runoff, this becomes a much less of an issue and will require a less frequent flushing. That will bring alklinity down. There are other ways to lower the pH in the pots too, slow or quick, if needed.

Also, I assumed it's not a pest problem as it's easy to check as well... but if you haven't, get a pocket microscope to verify that it's not mites or something else that's causing it. It's the first thing I do when I see a leaf problem. I kind of assume everyone else does it... I shouldn't assume :)
 
Lights could be a problem, however, if it is just the lower leaves and not the upper leaves showing issue, it could be a nutrient issue.

My primary guess is over watering. Every other day sounds like a lot! But I’m not as experienced with having mature trees in grow tents for head starts just as a disclaimer. If you water too much, that can cause a nutrient imbalance actually, especially with mobile nutrients: nitrogen, magnesium, potassium, or phosphorus. You could be having a nutrient lock out as well if it’s not the watering.

Personally, I wouldn’t fertilize so much next year if you do the same thing. If you’re having to pinch tops to stop growth because they’re getting too big, it doesn’t make sense to force more growth with weekly NPK ferts. They aren’t needed for health at that rate.
 
I assumed pH is in balance as it's easy to check. If you suspect pH issues, the only best thing to do is to check it and then adjust if needed. I would not try to guess here.

If you use only or mostly synthetics, salt build-up is a common issue, which can be taken care of with an occasional flush. It also depends on how you water you plants... if you water until a good runoff, this becomes a much less of an issue and will require a less frequent flushing. That will bring alklinity down. There are other ways to lower the pH in the pots too, slow or quick, if needed.

Also, I assumed it's not a pest problem as it's easy to check as well... but if you haven't, get a pocket microscope to verify that it's not mites or something else that's causing it. It's the first thing I do when I see a leaf problem. I kind of assume everyone else does it... I shouldn't assume :)
I have never checked for my soil PH, I guess it's something I have to start doing. Whats the best way of checking it, with the paper strips?

I give around 4 gallons of water to 6 plants every other day. I try not to give too much to drown them but I guess in order to flush out the salts I have to deep water them sometimes and toss the water out from the saucer. Its just gets hard with the plants being so tall now.

I had a gnat problem, they multiplied fast so for a while I was watering the trees from below while trying to catch the gnats from top. I put a nice layer of perlite with the sticky traps and I dont see much of them anymore.

I guess I should do a ph test first, what's a good brand you would reccomend off of Amazon?
 
Lights could be a problem, however, if it is just the lower leaves and not the upper leaves showing issue, it could be a nutrient issue.

My primary guess is over watering. Every other day sounds like a lot! But I’m not as experienced with having mature trees in grow tents for head starts just as a disclaimer. If you water too much, that can cause a nutrient imbalance actually, especially with mobile nutrients: nitrogen, magnesium, potassium, or phosphorus. You could be having a nutrient lock out as well if it’s not the watering.

Personally, I wouldn’t fertilize so much next year if you do the same thing. If you’re having to pinch tops to stop growth because they’re getting too big, it doesn’t make sense to force more growth with weekly NPK ferts. They aren’t needed for health at that rate.
With 80F and a full grown tree, they start getting thirsty. At the end of 2 days the leaves get very droopy, I assume it would get worse if I didnt water them.

As mentioned above I divide around 4 gallons of water to 6 plants. With the dehumidifier running the water gets collected back really quick. Almost half the water I put in gets pulled by the dehumidifier.

Its a great idea not to fertilize them this much next year. I thought with a really fast growing trees I would always have to feed them but they are outgrowing the tent in just 2 months.
 
I have never checked for my soil PH, I guess it's something I have to start doing. Whats the best way of checking it, with the paper strips?

I give around 4 gallons of water to 6 plants every other day. I try not to give too much to drown them but I guess in order to flush out the salts I have to deep water them sometimes and toss the water out from the saucer. Its just gets hard with the plants being so tall now.

I had a gnat problem, they multiplied fast so for a while I was watering the trees from below while trying to catch the gnats from top. I put a nice layer of perlite with the sticky traps and I dont see much of them anymore.

I guess I should do a ph test first, what's a good brand you would reccomend off of Amazon?
Amazon sells inexpensive soil pH test kits, those seem to work well for me.
 
100% to be honest im lazy so I will just use a PH strip and test that way. I think I have a meter somewhere but the strips are so easy!
 
I have 6 mature fig trees growing in my 8x4 growtent with 2 x 400w LED lights.
I think its a bit too crowded in there and should only go with 5 trees max next year.

My problem is that bottom leaves are starting to turn yellow, top growth seems fine. They are very close to the lights so I have pinched the buds to buy some time until I take them outside.

I am keeping the humidity around 45-50% with a dehumidifier, tempatures around 21-27C (70-80F) with lights on and off. Watering every other day and I fertilize with N-P-K weekly, giving fish fertilizer every 2-3 weeks and cal-mag every couple of weeks.

I also have two fans in the tent to circulate the air, one above the tree and one in the middle.

What am I doing wrong?
I agree with @Figgin' A response. But also check the run off water from your pots for ph. Often times if you fertilize well you can alter the ph of the media and get salt build up which can also crate nutrient lock out which can make it difficult for some plants to uptake nutrients like nitrogen.
 
@Armo Confirmed this again. Two of my most mature trees in the garage tent were the last ones to be transitioned outside started to drop leaves about a week and a half ago. Their canopies are large and dense. Only the lowest leaves were dropping. I've been wheeling them outside over the past 5 days to acclimate, and the leaf drop stopped on the second day, pretty much. I did not change the watering or fertilizing schedules.

leaves-drop.jpg
 
I used to have this happen when I grew indoors, it was mostly the bottom leaves that would yellow.
The rest of the plant was looking great, I attributed it to the shade the bottom ones were in due to the tightly packed growing area.
Was never really a problem since the plants were thriving.
 
@Armo Confirmed this again. Two of my most mature trees in the garage tent were the last ones to be transitioned outside started to drop leaves about a week and a half ago. Their canopies are large and dense. Only the lowest leaves were dropping. I've been wheeling them outside over the past 5 days to acclimate, and the leaf drop stopped on the second day, pretty much. I did not change the watering or fertilizing schedules.

leaves-drop.jpg
Mine looked exactly the same as these leaves. I took my trees out about 10 days ago. They acclimated nicely since the first day was cloudy, and on the second and third days they were in my outdoor tent. By the fourth day, they were fully outside without any sunburn. Not one leaf is changing color now.

I really think the leaves were dropping because of lack of lights — not enough light penetrating below and not enough fresh air circulating in the tent. I don’t know if the plants feel choked, but nothing beats their natural environment.

Ever since I took the trees outside, I even started getting a Black Manzanita breba ripening up.
 

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Mine looked exactly the same as these leaves. I took my trees out about 10 days ago. They acclimated nicely since the first day was cloudy, and on the second and third days they were in my outdoor tent. By the fourth day, they were fully outside without any sunburn. Not one leaf is changing color now.

I really think the leaves were dropping because of lack of lights — not enough light penetrating below and not enough fresh air circulating in the tent. I don’t know if the plants feel choked, but nothing beats their natural environment.

Ever since I took the trees outside, I even started getting a Black Manzanita breba ripening up.
I am pretty sure that it was a lack of light. Not my first year observing this. Unfortunately, unavoidable with long headstarts in crowded tents, but fairly benign.

Never got a chance to see or try a BMz breba. Please, share some pics and your review when it ripens.
 
I am pretty sure that it was a lack of light. Not my first year observing this. Unfortunately, unavoidable with long headstarts in crowded tents, but fairly benign.

Never got a chance to see or try a BMz breba. Please, share some pics and your review when it ripens.
I think next yesr i am gling to start them a bit more later. This yesr I started then mid February and by April they were already overcrowding in the tent. Next year I might try mid March head start.

As for the breba, I had it very early last year too. I am not good at desceibing taste but it was very very sweet and delicious.
Picture is from last year.
 

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To help make sure its not or overwatering, some rope or string dangling out of the bottom holes can help wick extra water away. Water finds the bottom of the pot and theres nowhere to go since air is not a medium. Then, Dam! Big fat waterlogged pot all waterlogged, dammed up & saturated from a wall or air. Adding the string give water an offramp or exit so your pot stays drained & in the happy zone of equilibrium, not supersaturated with nowhere for water to go except hold firm in that pot.

Just general advice & not a diagnosis of your issue fyi
 
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