Could the 1200 watt LEDs be the issue ?

Hey guys,

Having trouble identifying the source of a leaf discoloration / weakness problem.

Problem started way back in week 1 of grow. Yellow streaks on leaves started appearing. (almost like they were brushed yellow).

Leaves were also dry and crispy to the touch. I use a 1200 watt led that i was advised to raise further from the canopy (27" to 37"). That appeared to solve the dryness problem. That also solved the yellow streaking issue on the leaves.

Then a bigger problem popped up:

The majority of leaves started turning yellow starting from the outter edges and moving inwards (Week 4 through to Week 7)

Owing to sevedal bad experiences overfeeding past grows, I've drastically reduced my nute feeds to only having x3 nute feeds over the past 7 week period (Fox Farm's big grow at 1tbsp / gallon).

Quick Facts:

• At week 7 of grow.
• Single 1200 watt LED light at 37".
• X6 plants in 3 gallon pots.
• Quality soil (x2 weeks of only water).
• Soil is really airy (if that matters).
• PH of soil is 7.
• X3 nute feeds of only Grow Big FFM

Yellowing appears to be getting worse day by day. Any ideas? (defeciency or light related)

Uploaded early dryness + yellowing streaks (week 2) and current yellowing problem (week 7).

Get your soil PH down to 6.5 for better absorption, likely magnesium lockout, why are you feeding only water it looks hungry too

PH of soil is 7. But what PH Water are you feeding? I'd go in the 6.5-6.8PH range for soil in Veg.

The yellowing seems like the start of a (N) Nitrogen deficiency. Could be CaMg.

24" (2 ft) should be a fair distance. 24-36" on a "REAL Watt" 1000W Led should be okay.

Claflin_BU said:

Hey guys,

Having trouble identifying the source of a leaf discoloration / weakness problem.

Problem started way back in week 1 of grow. Yellow streaks on leaves started appearing. (almost like they were brushed yellow).

Leaves were also dry and crispy to the touch. I use a 1200 watt led that i was advised to raise further from the canopy (27" to 37"). That appeared to solve the dryness problem. That also solved the yellow streaking issue on the leaves.

Then a bigger problem popped up:

The majority of leaves started turning yellow starting from the outter edges and moving inwards (Week 4 through to Week 7)

Owing to sevedal bad experiences overfeeding past grows, I've drastically reduced my nute feeds to only having x3 nute feeds over the past 7 week period (Fox Farm's big grow at 1tbsp / gallon).

Quick Facts:

• At week 7 of grow.
• Single 1200 watt LED light at 37".
• X6 plants in 3 gallon pots.
• Quality soil (x2 weeks of only water).
• Soil is really airy (if that matters).
• PH of soil is 7.
• X3 nute feeds of only Grow Big FFM

Yellowing appears to be getting worse day by day. Any ideas? (defeciency or light related)

Uploaded early dryness + yellowing streaks (week 2) and current yellowing problem (week 7).

Click to expand...

Definitely a magnesium issue! If you've only fed grow big, it has very little magnesium in it, and your plants are quite big already! Add a teaspoon of epsom salt (per gallon) to your next watering, and keep it up as you go into flowering on every second watering if you won't be using any nutes with more mag. Also, as mentioned, try to get that ph of the soil down, slowly. 7 is on the border of high and you can run into more issues with lockout as she eats more into flower! I say water at ph 6-6.3. What exactly is the 'quality soil' you are using?

No its not the light its something with the soil your using.

Mag defficiency for sure maby just hungry in general. I would add 2 mil per gal of calmag with every feed from here on out. If you want to use just one thing pick a complete nutrient not one that wants you to use 3 bottles min. I would suggest Jacks, Mega Crop, and believe it or not there are lots who use fox farm soil and Flora Nova Bloom begining to end.

Blitz35 said:

Definitely a magnesium issue! If you've only fed grow big, it has very little magnesium in it, and your plants are quite big already! Add a teaspoon of epsom salt (per gallon) to your next watering, and keep it up as you go into flowering on every second watering if you won't be using any nutes with more mag. Also, as mentioned, try to get that ph of the soil down, slowly. 7 is on the border of high and you can run into more issues with lockout as she eats more into flower! I say water at ph 6-6.3. What exactly is the 'quality soil' you are using?

Click to expand...

Lol right! What quality soil. Had a guy tell me one time his local garden center mixed there own and sold it for 5 bucks a bag and it was the best soil he ever saw ( obviously why he was having problems lol) he brought some in to me ( managed a hydro store for 3 years) shit was sooo dense. Quality soil should self buffer as long as your not overfeeding. I run 50 50 soil/soiless and the little bit of soil in the mix is enough to buffer my ph.

Beachwalker said:

Get your soil PH down to 6.5 for better absorption, likely magnesium lockout, why are you feeding only water it looks hungry too

Click to expand...

On my previous run, i combined big grow with big bloom and the leaves used to claw like nothing ive seen. I also ran into severe nute toxicity in flower. So this time around im playing it safe.

Joint Monster said:

PH of soil is 7. But what PH Water are you feeding? I'd go in the 6.5-6.8PH range for soil in Veg.

The yellowing seems like the start of a (N) Nitrogen deficiency. Could be CaMg.

24" (2 ft) should be a fair distance. 24-36" on a "REAL Watt" 1000W Led should be okay.

Click to expand...

Ill be adding in a calmag supplement to see if that fixes the issue. How much epsom salt should i be adding into the feed (in addition to the grow big 1 tbsp/gal) ?

Dynamo626 said:

Mag defficiency for sure maby just hungry in general. I would add 2 mil per gal of calmag with every feed from here on out. If you want to use just one thing pick a complete nutrient not one that wants you to use 3 bottles min. I would suggest Jacks, Mega Crop, and believe it or not there are lots who use fox farm soil and Flora Nova Bloom begining to end.

Click to expand...

At the moment, i only have access to the 3 bottle feed from fox farm and a floranova 1-part (bloom) feed.

Dynamo626 said:

Lol right! What quality soil. Had a guy tell me one time his local garden center mixed there own and sold it for 5 bucks a bag and it was the best soil he ever saw ( obviously why he was having problems lol) he brought some in to me ( managed a hydro store for 3 years) shit was sooo dense. Quality soil should self buffer as long as your not overfeeding. I run 50 50 soil/soiless and the little bit of soil in the mix is enough to buffer my ph.

Click to expand...

Out of experience, i know exactly what type of issues you can face lol... Is there anyway of lowering the ph with kitchen ingredients? (stuff i can quickly get from the convenience store)

Update: just checked the water alone (ph= 6.95). About (ph = 6.75) with the big grow and Epsom salt.

Claflin_BU said:

Out of experience, i know exactly what type of issues you can face lol... Is there anyway of lowering the ph with kitchen ingredients? (stuff i can quickly get from the convenience store)

Click to expand...

Vinegar will lower your pH, and baking soda will raise it

So far, plants appear to be healthy and drinking their juice just fine.

Quick question for you guys; based on the image ive attached, would you say that 1200 watt led lamp is enough to cover the 3x3ft canopy ?

(i have x2 300 watt lamps lying around)