What deficiency is this (photo)

its happening in 2 out of 4 plants in a few of the fan leafs

Color change. Some plants change colors.
Especially with cooler temps during flowering.

a purple leaves usualy mean a phosphorusb shortahe

go go kid said:

a purple leaves usualy mean a phosphorusb shortahe

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sorry im not english , u mean lack of posphorous ? they are purple!

YES USUALY, HOW MANY LEAVES ARE TURNING THAT COLOUR?

Phosphorus. It's flowering now and wanting more.

very few fan leafs and only on 2 out of 4 plants , i just read that it could be
Molybdenum deficiency

how can i correct that ?


edit : >"Molybdenum deficiencies are usually present when there are also insufficient amounts of sulfur and phosphorus, so you might want to take a look into that as well. "

thanks guys

Skyhound said:

very few fan leafs and only on 2 out of 4 plants , i just read that it could be
Molybdenum deficiency

how can i correct that ?


edit : >"Molybdenum deficiencies are usually present when there are also insufficient amounts of sulfur and phosphorus, so you might want to take a look into that as well. "

Click to expand...

What lime said

seawees solution is a great sourse of micro nutrients,

thats a molybdamum def, your is deff differant to that one
HOW TO IDENTIFY?
Molybdenum deficiency will test the most eagle-eyed of cannabis growers. This one really is tough to diagnose correctly. Troubleshooting molybdenum deficiency will not only cost precious time, but most likely worsen the condition. Chlorosis striking the middle portion of cannabis plants foliage is commonly mistaken for nitrogen deficiency or calcium and magnesium deficiency.

In fairness, there is sound logic behind such assumptions. But don’t assume anything when it comes to unhealthy cannabis plants. Take a closer look. N deficiency tends to creep up a plant from the bottom up. Ca/Mg deficiency is rare in soil grows and more of a mid-late bloom problem in coco and hydro cultivation. Also, take note of the leaf discoloration, which will have brown crispy fringes and orange to pink shades in the centre. Eventually in a week or so, you will notice it is highly mobile as new growth begins to wither and curl.

how close to harvest are you?

i do have seaweeds from biobizz i will up the nutrients from 40% strength to 50% and use the seaweeds that have "alg·A·Mic is a revitalising product that contains a low level of NPK (Nitrogen, Phosphorus and Potassium) – making it impossible to overdose. "

go go kid said:

how close to harvest are you?

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midlle of 4th week of floration (55 days srtaain , probably 62~65)

its only needed in very small amounts, and seaweed has it, but its the cause of the problem you need to lookat if it is a def of some sort, your ph is something to look at, it maybe causing lockout, thats the only way youwill get a molybdimum deff

I'm going to side with lime too.

Molybdenum is needed in such small amounts, it's rare to see a deficiency using fertilizers.

The more likely chance is low ph locking out something like phosphorus. Not to point it out, though there are signs suggesting it's the case. (tip burn and claw)

I wouldn't be overly concerned about the purple leaves. If the plants are healthy, purple leaves almost always are too.

i always aim ph for 6.2 and 6.5 , i planted this strain last grow and used 50% nuts strenght and didnt saw that !! this grow i was using 40% to prevent tip burn and this happens :///////

Skyhound said:

i always aim ph for 6.2 and 6.5 , i planted this strain last grow and used 50% nuts strenght and didnt saw that !! this grow i was using 40% to prevent tip burn and this happens :///////

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Getting somewhere then. Post your total EC and NPK. Someone will be able to make a suggestion, for sure.

Aussieaceae said:

I'm going to side with lime too.

Molybdenum is needed in such small amounts, it's rare to see a deficiency using fertilizers.

The more likely chance is low ph locking out something like phosphorus. Not to point it out, though there are signs suggesting it's the case. (tip burn and claw)

I wouldn't be overly concerned about the purple leaves. If the plants are healthy, purple leaves almost always are too.

Click to expand...

The only time I’ve heard about molybdenum being an issue was regarding agriculture in central Australia.
A terrain that had been flushed for 200 million years.
Those of us on younger geography don’t need to worry.

Nutrient brands too. Someone on here likely uses the same.

im using full biobizz line with all mix soil at 40% strenght nuts , last grow used with 50%, didnt had this , i dont mesure ~EC :\ , im adding alg a mic from biobizz to help and up to 50 % . One other thing , last grow i watered 1 day waited 3 days and on 4th day watered again . Now is coolder i only water at 5 day