420 Magazine Background

Need your expert advice

Swampass

New Member
Howdy gang. I have month old plant thats just starting to show signs of yellowing. Im assuming over watering or a nutrients problem. I grow under a 300 watt LED and use AN micro, grow and bloom at half strength. Last time I watered the plant it wilted bad for a day put perked back up but the yellowing is started. Im afraid of doing opposite of what it needs. Thanks guys and gals.
IMG_1312_zpsf4e633bb.jpg
 

Swampass

New Member
Re: Need your expert advice.

Here is more info:
Strain- not known. but it looks like an indica. Was an old seed i had.
-1 plant
-Vegetative stage 2nd week
-Indoor under 300 watt LED
-in 1.6 gallon growers pot in soil. Going to transplant in final container later this week.
-soil mixture is spagnum with perlite. no nutrients in soil
-air conditioned room with exhaust fan. Temp is usually around 88F
-was watering every three days with nutrients when the container felt lite.
-using advanced nutrients micro, grow and bloom. half strength
-room is a 6x6 with 7 foot ceiling.

Im new to advanced nuts so maybe I shouldn't feed with every watering. Thanks gang!
 

Antics

420 Member
Re: Need your expert advice.

And the rest of the information?

What Strain is it?
Is it Indica, Sativa or Hybrid? What percentages?
How Many Plants?
Is it in Vegetative or Flowering Stage?
If in Vegetative Stage... How Long?
If in Flowering Stage... How Long?
Indoor or Outdoor?
Soil or Hydro?
If Hydro, Reservoir size?
If Hydro, Reservoir Temperature?
If Hydro, what type of Medium?
If Hydro, what type of Setup?
If Soil... What is in your Mix?
If Soil... What Size Pot?
Size (Wattage) of Light? How Many?
Is it Air Cooled?
Temperature of Room/Cabinet?
RH of Room/Cabinet?
PH of Medium or Reservoir?
Any Pests?
How Often are you Watering?
Type and Strength of Fertilizers used?
Size or Square Footage of Room?
 

Swampass

New Member
Re: Need your expert advice.

Hey there antics. I posted the other info above your last post. Only thing I left out was PH and its around mid to high 6.
 

Antics

420 Member
Re: Need your expert advice.

Thanks for filling everything out.

The issue appears to be a magnesium deficiency in its early stages.
cannabis_leaf-deficiencies3113.jpg


Is your growing medium just peat/perlite? Or is it soil, amended with peat and perlite?
As for a few other pointers on your grow:
Transplant: Try to follow the guideline of 1 gallon of pot size for every 12"/30cm of plant height you expect to see. 3 Gallons works, but 5 gallons will work for virtually all indoor grows. (Some strains grow much larger roots than others). I also find it's easier to manage the soil mass, and prevent it from breaking apart by transplanting a small pot, like a solo cup size, into its final container. If the soil breaks apart during transplant, it can damage roots severely, opening the plant up to infections, or at the very least, stunted growth.

88F sounds a little high. The most common range I see is 70-80F lights on, and as high as 85 lights on. If you can bring the temps down a few degrees it can help.

Every 3 days watering could be accurate, it depends on your soil mix. Make sure the soil is well dried out before watering again. I use a moisture meter probe to check moisture level, but I find that you can determine moisture level just by feeling the soil that sticks to the probe if you have a little prior gardening experience.

You'll definitely need to spread out the waterings when you transplant into the final pot.

You should only need nutes once a week. and I've never needed nutes before week 3 or 4. Check PH again to get an accurate reading before supplementing Magnesium. Your micro nutes already contain Magnesium, so I'm still wondering about your PH. What type of measuring device are you using?
 

Swampass

New Member
Re: Need your expert advice.

Thanks for the reply.
Im now fairly confident its bleaching from LED lights. Leaves that are not in direct light have no signs of yellowing. I had light at 12" from plant. Moved it to 20 inches. Even 300 watt LED puts off very little heat so i had plant prob closer than needed. Went ahead and transplanted to 5 gallon container for its final run and to dilute nuts if that is the issue. Im in south Florida so Temp is hard to regulate. When its 98-99 outside its hard to get a 20 degree drop in temp. Ive had plants thrive at temps to 95. I usually can keep temp in the high 80's no problem. Im new to the LED and indoor stuff. We get so much rain its hard to manage the outdoor grows here lately. Im not an expert by any means. Thought Id try indoor for more control over environment. Ill report back to see if this clears things up.
 

J189RFC

New Member
Most often bleaching will happen when the LED is within 2-3 inches of a plant. It also doesn't look like that. We are talking white and burnt tips. In this forum we see it more with the 1000w + lights and usually only during the flowering period. I would be tempted to agree with the prognosis of cal/mag def. One of the weird things LEDs do to plants is make them more hungry for cal/mag than other lights. Generally most peoples feeding regiments don't change when they get LEDs but they do mention needing to add more cal.mag.
 

Swampass

New Member
You are correct the problem ended up being a Cal mag issue. That plant ended up being a hermie. I had to throw it out. That was actually the first plant I ever grew and had no idea what I was looking at but definitely classic signs of Cal mag. I appreciate your reply.
 
Top Bottom