Under/Over fed, light burn, other issue?

[MGD420]

Just a bit curious as to whats going on with this girl.

Auto, 22/2 light schedule, feeding sensi bloom A&B 4ml / litre

leaves that are rusty seem to be more at the top closest to the light.

The other plant seems to be doing good

 

[Bill284]

Just a bit curious as to whats going on with this girl.

Auto, 22/2 light schedule, feeding sensi bloom A&B 4ml / litre

leaves that are rusty seem to be more at the top closest to the light.

The other plant seems to be doing good

Hey MGD
Looks like a little nutrient burn.
Is 4 ml/l the recommended dose?
Try backing it off a bit?



Stay safe
Bill284

 

[bluter]

looks like a little pk excess. agree with @Bill284 on the nute levels.

 

[Sparkey224]

Agree with bill and bluter. Raise the light too a little bit.
I don't understand why folks want to put their plant so close to the light.
Cheers

 

[MGD420]

Hi @Bill284 how's thing's bud ? Hope thing's are good with you too @bluter
Thanks for the help guy's as always it's appreciated. I'll drop the feed down to around 3ml and see how she does.
@Bill284 yes 4ml is the recommended dose for the sensi bloom when in flower, i managed to get my hands on some MegaCrop 9-7-14. @bluter has mentioned it a few times to try it but haven't had a chance to use it yet as using the sensi until it runs out, the MC is hard to get here in the uk though.

Hey @Sparkey224 how's thing's. Unfortunately i've no more room to move the light it's already at it's max height in the tent and the plant in question has already been supercropped to prevent it from touching the light.

 

[Bill284]

Hi @Bill284 how's thing's bud ? Hope thing's are good with you too @bluter
Thanks for the help guy's as always it's appreciated. I'll drop the feed down to around 3ml and see how she does.
@Bill284 yes 4ml is the recommended dose for the sensi bloom when in flower, i managed to get my hands on some MegaCrop 9-7-14. @bluter has mentioned it a few times to try it but haven't had a chance to use it yet as using the sensi until it runs out, the MC is hard to get here in the uk though.

Hey @Sparkey224 how's thing's. Unfortunately i've no more room to move the light it's already at it's max height in the tent and the plant in question has already been supercropped to prevent it from touching the light.

I’m good
Some nutrient schedules will have a peak that’s not in line with your plants.
If you watch her how she reacts and grows when you feed her you can tell if she needs to be at maximum.
Look at the leaf shape and color.
Start there learn how they react.
Sometimes the schedule is more of a guideline.
Different phenos sometimes have different needs




Stay safe
Bill284

 

[MGD420]

I’m good
Some nutrient schedules will have a peak that’s not in line with your plants.
If you watch her how she reacts and grows when you feed her you can tell if she needs to be at maximum.
Look at the leaf shape and color.
Start there learn how they react.
Sometimes the schedule is more of a guideline.
Different phenos sometimes have different needs




Stay safe
Bill284

Having colour blindness doesn't help. Certain shades throw me off under the lights. Dark green leaves not an issue, when they're a lighter shade of green i always think they need fed. The plant was probably fine up until i upped her feed she just looked light in comparison.

She's a greedy plant i know that much. I have 3 plant's going at the moment and she takes almost double the amount of water/feeding before run off compared to the other two

 

[Bill284]

Having colour blindness doesn't help. Certain shades throw me off under the lights. Dark green leaves not an issue, when they're a lighter shade of green i always think they need fed. The plant was probably fine up until i upped her feed she just looked light in comparison.

She's a greedy plant i know that much. I have 3 plant's going at the moment and she takes almost double the amount of water/feeding before run off compared to the other two

That’s great you always feed to run off.
Sorry about the color blindness.
And the LED’s don’t make it easy.
I understand.
It takes time.



Stay safe
Bill284

 

[Delps8]

good to see 22/2. I've run plants at 24/0 throughout veg but have settled o 20/4.

You have a nutrient imbalance - the question is what caused it? You might solve it by changing your nutrient mix but cannabis is happy with nutrients in a wide range of concentrations. If you're feeding the recommended mix and recommended strength then there might be something in the environment that's causing the nutrient imbalance.

What are your temperature and RH values?

There's lots of foliage in there so I suspect that you're feeding your plants well (light is how a plant makes food). What's your fan set up like.

The damage to those leaves didn't happen overnight. What changed about 7-10 ago?

What light are you using and what's the dimmer % and hang height?

Cutting back on nutrients rarely hurts because most growers give their cannabis plants more nutes than are needed to be "sufficient" but something changed at least a week ago that has put things out of whack.

 

[MGD420]

good to see 22/2. I've run plants at 24/0 throughout veg but have settled o 20/4.

You have a nutrient imbalance - the question is what caused it? You might solve it by changing your nutrient mix but cannabis is happy with nutrients in a wide range of concentrations. If you're feeding the recommended mix and recommended strength then there might be something in the environment that's causing the nutrient imbalance.

What are your temperature and RH values?

There's lots of foliage in there so I suspect that you're feeding your plants well (light is how a plant makes food). What's your fan set up like.

The damage to those leaves didn't happen overnight. What changed about 7-10 ago?

What light are you using and what's the dimmer % and hang height?

Cutting back on nutrients rarely hurts because most growers give their cannabis plants more nutes than are needed to be "sufficient" but something changed at least a week ago that has put things out of whack.

They were on 20/4 but changed it around 2 weeks ago, upped the light intensity from 50% to 70% over the past week or two with the plants going into flower same with their feed, upped that around 2 weeks ago as the the leaves were looking a light green.
Fan set up, one large fan at the top of the canopy, lights are mars hydro sp3000 @70%
lights are 8 inch from the top of the tallest plant with no room for moving them any further
temp 23c and rh is 68%
I know the rh is high but i have tried to get it down without burning through silly amounts of energy using a large dehumidifier like i have done in the past. The RH sit's around the same levels throughout the entire house not just the tent so it's either deal with it or run dehumidifiers 24/7 that cost more daily than the entire setup costs to run daily

 

[Bounce3d]

hi

i think you have a cal/mag problem

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[Bounce3d]

it could be the over feeding has affected the cal/mag

 

[SmokingWings]

it could be the over feeding has affected the cal/mag

Mulder's Charts are always interesting to sort out. Shown on this chart, and from what I remember from other charts with more individual nutrients, the only nutrient in excessive amounts that has an effect on Calcium is Phosphorous. But excessive amounts of Calcium will have an antagonistic effect on just about every other nutrient that will be shown on the chart; and that includes Magnesium which is often paired up with Ca so that both are applied to the plant at the same time.

That might be why Calcium and Magnesium are both in the same product. The science has come up with an acceptable ratio between the two nutrients that lets them play nicely with each other. (Notice that excessive amounts of Magnesium do not have an adverse or antagonistic effect on Calcium.)

 

[Delps8]

They were on 20/4 but changed it around 2 weeks ago, upped the light intensity from 50% to 70% over the past week or two with the plants going into flower same with their feed, upped that around 2 weeks ago as the the leaves were looking a light green.
Fan set up, one large fan at the top of the canopy, lights are mars hydro sp3000 @70%
lights are 8 inch from the top of the tallest plant with no room for moving them any further
temp 23c and rh is 68%
I know the rh is high but i have tried to get it down without burning through silly amounts of energy using a large dehumidifier like i have done in the past. The RH sit's around the same levels throughout the entire house not just the tent so it's either deal with it or run dehumidifiers 24/7 that cost more daily than the entire setup costs to run daily

Increased feed levels two weeks ago + increased light levels.

I see no symptoms of excess light but it's possible that the combination of increased level of photosynthesis plus the cold and wet temps is causing a nutrient issue.

At 23°C and 68% RH, your plants are having a hard time transpiring. The temperature + RH are like a cool, wet blanket so it can't throw off moisture which means that it can't take up much water. The increased photosynthesis is causing additional growth but the plant can't transpire because of the low VPD.

With those values, your temp + RH, I'll use the term VPD because it's convenient, is brutally low — your environment is a little bit moist for germination. With all of that foliage and only one fan, RH in the plant (which is what counts) is significantly higher.

Ambient RH readings are of some value but it's the RH adjacent to the plant and in the canopy that impacts transpiration. Out of interest, get some RH readings just above the canopy and in the plant. Those are the values that matter because that's the RH level for the plant.

If you can't get RH down, can you get temperature up?

In addition, can you increase air flow and what about an extraction fan? I run fans at 2 meters/second and change the air 2.x times per minute (I forget the exact number).

The vapor pressure deficit chart below shows that your plants are dealing with a VPD of 0.7. Cannabis grows better in warmer temps. If you can't get RH down, so be it but with that much water in the air, your plants will do much better at around 30°C.

Perhaps I've missed it but is this soil or hydro?

70% for that light and hang height is OK but you've got an uneven canopy so I would cant the light - drop the light on the left side of the tent so that the hang height is about the same as it is on the right. It looks weird but more photons = more weed and the flower top on the left are probably getting 200µmol less than the flower tops on the right. That 200µmol is about a 15-18% loss in crop yield.

 

[MGD420]

Increased feed levels two weeks ago + increased light levels.

I see no symptoms of excess light but it's possible that the combination of increased level of photosynthesis plus the cold and wet temps is causing a nutrient issue.

At 23°C and 68% RH, your plants are having a hard time transpiring. The temperature + RH are like a cool, wet blanket so it can't throw off moisture which means that it can't take up much water. The increased photosynthesis is causing additional growth but the plant can't transpire because of the low VPD.

With those values, your temp + RH, I'll use the term VPD because it's convenient, is brutally low — your environment is a little bit moist for germination. With all of that foliage and only one fan, RH in the plant (which is what counts) is significantly higher.

Ambient RH readings are of some value but it's the RH adjacent to the plant and in the canopy that impacts transpiration. Out of interest, get some RH readings just above the canopy and in the plant. Those are the values that matter because that's the RH level for the plant.

If you can't get RH down, can you get temperature up?

In addition, can you increase air flow and what about an extraction fan? I run fans at 2 meters/second and change the air 2.x times per minute (I forget the exact number).

The vapor pressure deficit chart below shows that your plants are dealing with a VPD of 0.7. Cannabis grows better in warmer temps. If you can't get RH down, so be it but with that much water in the air, your plants will do much better at around 30°C.

Perhaps I've missed it but is this soil or hydro?

70% for that light and hang height is OK but you've got an uneven canopy so I would cant the light - drop the light on the left side of the tent so that the hang height is about the same as it is on the right. It looks weird but more photons = more weed and the flower top on the left are probably getting 200µmol less than the flower tops on the right. That 200µmol is about a 15-18% loss in crop yield.

Hydro, the plants are in coco. I could raise the temps by hooking up a small heater and drop the light to one side.
I think the uneven canopy is due to the plants being planted a week or two apart. there is actually 3 plants in the tent at the moment one was planted 2 - 3 weeks behind the other two.
I could also turn the extraction up more, the fan is way oversized for the size of tent but i have noticed even when it's turned up it doesnt drop the RH much. RH is 63 at the top of the canopy and temp is 24. Not sure if my gauge for the ac infinity is giving the right reading as its way off compared to the hygrometer in the tent which gave the above readings. 63% and 24c

 

[Delps8]

Hydro, the plants are in coco. I could raise the temps by hooking up a small heater and drop the light to one side.
I think the uneven canopy is due to the plants being planted a week or two apart. there is actually 3 plants in the tent at the moment one was planted 2 - 3 weeks behind the other two.

Got it. I had what I called "Twins" grow. I tried use the one light for both plants. No joy. I put so much light on Jeff that it fox tailed and ended up getting a little Vipar XS1500 anyway.

These plants were same strain, germinated the same date, same seed packet. Go figure.

I could also turn the extraction up more, the fan is way oversized for the size of tent but i have noticed even when it's turned up it doesnt drop the RH much. RH is 63 at the top of the canopy and temp is 24. Not sure if my gauge for the ac infinity is giving the right reading as its way off compared to the hygrometer in the tent which gave the above readings. 63% and 24c

Higher temp and/or lower RH will help. You've got a fair amount of foliage in there and low VPD like that increases the odds of bud rot. That sucks.

 

[MGD420]

Got it. I had what I called "Twins" grow. I tried use the one light for both plants. No joy. I put so much light on Jeff that it fox tailed and ended up getting a little Vipar XS1500 anyway.

These plants were same strain, germinated the same date, same seed packet. Go figure.

Higher temp and/or lower RH will help. You've got a fair amount of foliage in there and low VPD like that increases the odds of bud rot. That sucks.

Hopefully there's no bud rot, even with the heater on, exhaust fan turned up there's almost no drop in humidity, still sitting in the 60's and temp is 1c higher. The humidity in the entire house is sitting around the same let alone just the tent

 

[bluter]

Hopefully there's no bud rot, even with the heater on, exhaust fan turned up there's almost no drop in humidity, still sitting in the 60's and temp is 1c higher. The humidity in the entire house is sitting around the same let alone just the tent

air movement is key. even with the higher rh%. moving as much air as possible will keep you under control. turn up the exhaust fan, and add another couple 4 or 6 inch clip fans to the tent. keep larger fans at or above the canopy pointed at the tops, and the smaller ones, lower or underneath pointing up.

i've brought a few grows home with late high rh% this way and avoided the bud rot. i had some on the last 2 grows and arrested it on the last one this way.

all the crap about vpd won't help you. the issue is the rh. the best way to control it is air movement. adding heat in summer to hit a vpd number is sheer nonsense.

 

[MGD420]

air movement is key. even with the higher rh%. moving as much air as possible will keep you under control. turn up the exhaust fan, and add another couple 4 or 6 inch clip fans to the tent. keep larger fans at or above the canopy pointed at the tops, and the smaller ones, lower or underneath pointing up.

i've brought a few grows home with late high rh% this way and avoided the bud rot. i had some on the last 2 grows and arrested it on the last one this way.

all the crap about vpd won't help you. the issue is the rh. the best way to control it is air movement. adding heat in summer to hit a vpd number is sheer nonsense.

That was my understanding aswell bluter, as long as there's plenty air movement the humidity shouldn't affect the grow in the same way it would if the air was stagnant. A good few growers online say the same but it's even better to hear it straight from someone i know and trust on the forum.
I've got another couple of fans there that i will set up for the bottom of the tent over the next day or two.
I think where i stay doesn't help to be honest, weathers shite for the best part of the year, summer consists of 3 maybe 4 days of sun and then pisses it down for the rest of the time. Surely doesn't help.

 

[Delps8]

Hopefully there's no bud rot, even with the heater on, exhaust fan turned up there's almost no drop in humidity, still sitting in the 60's and temp is 1c higher. The humidity in the entire house is sitting around the same let alone just the tent

1°C — well it's better than 1°F!