Update on previous post (yellow leaves)

[MikeHunt000]

Hi, I posted here before about some of the lower leaves turning yellow.

I don't think I stopped the issue, and also think I gave them nutrient burn.
The plant in the photo is critical X cheese auto (but been told on here they are photoperiod ones) they were planted around 15th of may. I stopped feeding and now have just been watering every 2 to 3 days depending on the soil dryness.

How long is likely to be left until they finish flowering? Will the yellow leaves take over the plant before then? Will the buds get much bigger? (It's been flowering for about 2 weeks)

 

[Moe.Red]

Well, you have a while. The yellow in the lower leaves is typically caused by the plant stealing mobile nutrients from old growth to fuel new growth.

“Immobile” Vs. “Mobile” Nutrients​

One way to diagnose nutrient problems is by their location. Some nutrients are immobile. Once they are set in place in the plant, they cannot move from their location. Other nutrients are mobile. When there is a limited supply, they go where the action is—usually to the top of the canopy.

IMMOBILE MINERALS​

Boron (B), Calcium (Ca), Copper (Cu), Iron (Fe), Manganese (Mn), Molybdenum (Mb), Sulfur (S) and Zinc (Zn) are utilized by the plant in ways that prevent them from being moved or movable on a limited scale. These are called immobile or intermediately movable nutrients. Calcium, for example, is permanently laid down in cell walls and cannot be moved. When these nutrients are deficient, the plant cannot transport them from older leaves so new growth occurs where immobile nutrient deficiency symptoms show up as deformed leaves. With extreme deficiency they may die back. This is most likely to happen with Boron and Calcium deficiencies.

MOBILE NUTRIENTS​

Nutrients that the plant can move around are called mobile nutrients. Nitrogen (N), Magnesium (Mg), Phosphorous (P), Potassium (K), and Nickel (Ni) are examples. These nutrients can be cannibalized and moved to support new growth elsewhere in the plant.
When there is a deficiency, plants typically move the nutrients from old growth to the top of the canopy, where they will be utilized most effectively. Deficiency symptoms then show up on the older leaves from which the nutrients are being removed.

“Nutrient deficiencies can, at times, serve a purpose—for both the plant and the grower. ”

— ED ROSENTHAL



To some extent, this is not a bad thing. Most growers would not let those original huge fan leaves to the end anyhow as they loose efficiency of photosynthesis when they get old. and just block light and air movement without much benefit to the plant.

 

[Mechman60]

Hi, I posted here before about some of the lower leaves turning yellow.
View attachment 1262744View attachment 1262745View attachment 1262746View attachment 1262747
I don't think I stopped the issue, and also think I gave them nutrient burn.
The plant in the photo is critical X cheese auto (but been told on here they are photoperiod ones) they were planted around 15th of may. I stopped feeding and now have just been watering every 2 to 3 days depending on the soil dryness.

How long is likely to be left until they finish flowering? Will the yellow leaves take over the plant before then? Will the buds get much bigger? (It's been flowering for about 2 weeks)

On my Northern Lights it yellowed and dropped most fans after my last two flushes. It turned out Great.

 

[AfghaniGuy]

A few years ago when I grew Kosher Kush, I didn't know what the hell I was doing and didn't trim lower fan leaves early and they grew into stalks and got so heavy they broke off. Lesson learned.