Can someone diagnose my Flowering Plant leaves?

[healthdude38]

Hey there fellow growers,

Im doing a DWC grow, im on week 7 of flowering and the plants are showing some symptoms that i dont know what it is..

Symptoms started about 2 weeks ago, at first i thought it was nute burn (which i still think it also was that), so i gave it only Ph'd water to flush the plant for this last week, the 2 times i went to check on the ph during this week the ph had become higher and out of range which i think made everything worse and now they look effed up. Somebody any ideas on what i should do?

Ps: the symptoms are starting in the higher leaves and going down the plant, the bottom leaves are not as damaged as the top ones..

 

[BigBlonde]

Could there be some light stress or burn?

 

[healthdude38]

Could there be some light stress or burn?

Idk, maybe? My 1000w Led (spiderfarmer) is about 20cm away from the plant

 

[BigBlonde]

Idk, maybe? My 1000w Led (spiderfarmer) is about 20cm away from the plant

That's about 8 inches and that could be too close. I'm not familiar with that brand of light, but I've noticed LEDs need to be farther away.

 

[healthdude38]

That's about 8 inches and that could be too close. I'm not familiar with that brand of light, but I've noticed LEDs need to be farther away.

I just pulled up the lights a bit. Temperature was 29 C°

But the browning on the leaves doesn't seem to be caused by the heat otherwise the other plants would also be showing the same symptoms?

 

[Trash_2002]

I just pulled up the lights a bit. Temperature was 29 C°
View attachment 1982507
But the browning on the leaves doesn't seem to be caused by the heat otherwise the other plants would also be showing the same symptoms?

they are all the same cultivar clones?

 

[MIGrampaUSA]

Light burn is caused by setting the intensity too high. It has more to do with overwhelming the plant with photons than it does with heat. 1000w of LED is a very powerful light. Double the light distance at minimum or turn the light down. Your plant is showing calcium deficiencies which is being magnified by too much light.

Here's a read on diagnosing calcium deficiency in cannabis.

How to Recognize and Treat Calcium Deficiency in Cannabis Plants

This article explores the importance of calcium and how to spot calcium deficiency in cannabis plants. Analytical Cannabis also offers tips to help prevent and treat the problem.

www.analyticalcannabis.com

 

[healthdude38]

they are all the same strain?

No, they are all different strains

The one with the symptoms is IN Z AIR by perfect tree seeds..

 

[BigBlonde]

But the browning on the leaves doesn't seem to be caused by the heat otherwise the other plants would also be showing the same symptoms?

What @MIGrampaUSA said!

 

[healthdude38]

Light burn is caused by setting the intensity too high. It has more to do with overwhelming the plant with photons than it does with heat. 1000w of LED is a very powerful light. Double the light distance at minimum or turn the light down. Your plant is showing calcium deficiencies which is being magnified by too much light.

Here's a read on diagnosing calcium deficiency in cannabis.

How to Recognize and Treat Calcium Deficiency in Cannabis Plants

This article explores the importance of calcium and how to spot calcium deficiency in cannabis plants. Analytical Cannabis also offers tips to help prevent and treat the problem.

www.analyticalcannabis.com

Ok I tuned it down to 700w now.. should I go even lower?
Will this not yield less? I always thought more light = more weight

 

[MIGrampaUSA]

No, they are all different strains

The one with the symptoms is IN Z AIR by perfect tree seeds

Ok I tuned it down to 700w now.. should I go even lower?
Will this not yield less? I always thought more light = more weight

There is truth to that to an extent. More light = more weight in a healthy plant. However there becomes a point where you can deliver too much light regardless of how well they are cared for. Your light was designed for the professional grower to use in a commercial grow setting. These lights are usually higher up than what a tent grower would have it set at. For most home-grow set-ups. 1000w is over-kill.

If you have a smart phone, download one of the free PPFD apps. This should give you a ballpark idea of where to set your light intensity.

Edit: You can still use your light. Just plan on the 700w-800w area to be your golden grow zone during flower ... and turn down light intensity a bit (10%) during late flower to trick the plant into sensing that winter is around the corner.

 

[healthdude38]

There is truth to that to an extent. More light = more weight in a healthy plant. However there becomes a point where you can deliver too much light regardless of how well they are cared for. Your light was designed for the professional grower to use in a commercial grow setting. These lights are usually higher up than what a tent grower would have it set at. For most home-grow set-ups. 1000w is over-kill.

If you have a smart phone, download one of the free PPFD apps. This should give you a ballpark idea of where to set your light intensity.

Edit: You can still use your light. Just plan on the 700w-800w area to be your golden grow zone during flower ... and turn down light intensity a bit (10%) during late flower to trick the plant into sensing that winter is around the corner.

Thank you, I just went a measured the ppfd with my phone. With 1000w on the ppfd was around 55k to 67k, and with 700w it's around 36k to 45k ( it's higher in the middle of the grow room)

How much is too much? What numbers should I be aiming for with the ppfd?

 

[MIGrampaUSA]

Thank you, I just went a measured the ppfd with my phone. With 1000w on the ppfd was around 55k to 67k, and with 700w it's around 36k to 45k ( it's higher in the middle of the grow room)

How much is too much? What numbers should I be aiming for with the ppfd?

Here's a quick read that might help you sort all this out ...

Understanding Grow Light PAR, PPFD, Wattage And DLI (2023)

How much PAR does my marijuana or vegetable plant need to maximize harvest? Find out the minimum PAR value you plants need before you buy a grow light.

420expertguide.com

 

[SchwiftyGrower]

@MIGrampaUSA wont steer you wrong! Great info as always!

 

[Scrogger2190]

Yeah 1000w is overkill for a home setup. I normally use an 800w led with lm301b diodes. TRUE 800w pulls 800 from wall. And I had to dim it down to 50% at roughly 12" because I run a fresh air setup. But I wanted a light powerful enough that when I upgrade to a sealed co2 setup I wouldn't need to get a new light. The lm301b and h diodes are very powerful led technology. I ended up pulling almost 2lb out of a 4x4 area with it on 50%. Would highly recommend investing in a light meter to understand the amount of light you're hitting your plants with a little bettter

 

[MIGrampaUSA]

There are many good reasons to use a light more powerful than you need. I have 2 ROI-E720's in an oversized 4 x 8. Using the Growers Choice master controller, each of those lights can run at 800 watts. Depending on strain, I am usually in the 500 to 600 watt range per light.

The advantage is less heat and higher efficiency. I wouldn't want the OP to feel like they over - spent. That light is use-able and offers great benefits being used at less than 100%.

 

[Scrogger2190]

There are many good reasons to use a light more powerful than you need. I have 2 ROI-E720's in an oversized 4 x 8. Using the Growers Choice master controller, each of those lights can run at 800 watts. Depending on strain, I am usually in the 500 to 600 watt range per light.

The advantage is less heat and higher efficiency. I wouldn't want the OP to feel like they over - spent. That light is use-able and offers great benefits being used at less than 100%.

Yeah I definitely agree. He didn't waste money. It's definitely scalable into a co2 setup, and iirc you actually get a better footprint at 100% at higher height right? I'm just saying a light meter would be very beneficial for him right now.

 

[MIGrampaUSA]

Yeah I definitely agree. He didn't waste money. It's definitely scalable into a co2 setup, and iirc you actually get a better footprint at 100% at higher height right? I'm just saying a light meter would be very beneficial for him right now.

I agree, but I would pony up the extra funds for a quantum light meter. Those measure in ppfd and calculate dli. The phone apps are useful in the meantime.

 

[Scrogger2190]

I agree, but I would pony up the extra funds for a quantum light meter. Those measure in ppfd and calculate dli. The phone apps are useful in the meantime.

Yeah personally I've never used a phone light meter so idk how accurate they are. The quantum meter is what I'm used to. Measuring in ppfd is tye way to go once you get the formulas down its really nice :)

 

[healthdude38]

Here's a quick read that might help you sort all this out ...

Understanding Grow Light PAR, PPFD, Wattage And DLI (2023)

How much PAR does my marijuana or vegetable plant need to maximize harvest? Find out the minimum PAR value you plants need before you buy a grow light.

420expertguide.com

Im a bit confused, it says in flower a ppfd of 400 to 900ish is needed?? Im getting 67000.. this can't be right can it?

I think even if a put the light at 20% I will have more than 1000 ppfd