Well this is the second time this has happened to me now...

BB Cheese 6 weeks into flowering the larger fan leaves start drying up going yellow and dying.

Now at 7 weeks and the smaller leaves are going yellow drying up to a crisp (literally) which is going to effect the bud at harvesting.

I thought it was lack of watering/humidity so i increased the water schedule a bit and mist sprayed them twice a day but its getting worse by the day.

any thoughts please???

Need more info than that matey, what system are you using or are you using compost/soil, what feeding ratio's are you using, if hydro what is the ec level at and ph level assuming you are using hydro, need a pic really that would help, if the leaf tips are burnt this would indicate overfeeding. It could also be underfeeding, then again could be mg def, need a pic.

Also you stated you are misting, would not mist anything in flower otherwise you may end up with bud rott, if you have to do any spraying avoid bud sites, would never mist with lights on.

I hardly ever mist let alone twice a day, once every 2 weeks and never in flower, occationally mist mg if yellowing appears lower down the plant.

Here is a pic.

Grown in Bio bizz all mix, using bio bloom and bio grow with recommended schedule.

temps are around 27C and humidity is 30%

400W gro lux light in bud box tent

How much of each are you giving them?

Hi asout, i was under the impresion that misting in the floweriing stage(late) isnt good for your gorw, sling it into google you will pick something up there, I'll have a look for ya in a few hour's(got to take misses to the boozer).
Hope ya sort it,
Peace out.
VEGHEAD.

Any posts made by me are purely fictional in nature and by no means is anything I say to be taken seriously. I do not grow or condone the growing of anything not legal. Any and all pictures I post are pictures widley available on the internet and any discussions I am involved in are purely hypothetical or are commentary in nature and should not constitute advice or be considered advice to assist in activities that are deemed illegal.

about 2 or 3mls per litre, 1 litre every 2 days

2 or 3? 2 or 3 of what mate?

And i suspect that you misting them twice a day hasn't done them any favours whatsoever.

2 or 3 of bloom and 1 of grow, i have stopped the misting now!

I have the same exact problems with my cheese mate, will be following this with interest, I am using roughly the same ml as you and terra flores and bio bizz stimulator - also the second time for mine and its driving me nuts.

only thought so far is that its too much chems and its locking them up, but its a pain in the arse

Looks like a magnesium deficiency

Water with 2 teaspoons of Epsom salts (magnesium sulphate) per gallon of water. For fast results, spray foilage with a 2 % solution of Epsom salts.Greening starts at the top of the plant and moves downward. Add same dose until symptoms dissapear or apply magnesiums sulphate monnohydrate.

Keep root zone and nutrient solution 70-75 f

Keep ambient air temp at 75 f in day and 65 f night

Keep soil above ph 6.5 and lowetr the ec slightly for a week

Matt

It doesn't look anything like (Mg) deficiency mate!

Sorry

Manganese ?

So are we sure its the Epson salts deficiency or not? as im ready to give it a try......

It looks very much like a toxcicity of one kind or another, hence the leaf claw and general twisiting of leaves, probably caused by overfeeding, misting has only made the problem worse and probably locked out other nutrients as well.

I would drop your feeding ratio, if that was hydro and I know it isn't the ec at 4ml per litre would be close to an EC of 2.0, granted soil is different but the food ratio and amount applied would be ruffly the same quantity.

It looks like N toxcicity based on having this problem before and it looking like that picture but not as drastic, personally would flush for 2 days and lower nutes.

Just re-read ya first post, you only have 2 weeks left based on the BB Cheese flowering period being 9 weeks max, I also flush for the last two weeks, or rather use a small amount of grow for the last two weeks to improve bud taste.

serious nute burn that is , from misting and rootfeeding together prob, only thing you can do now is to just give water till they finished, also 1 litr every 2 days aint helping , try giving them a lot more water and then going 3 or 4 days before you water them again , aka the wet/dry cycle

Yeah when you water, stand them in a tray, and water till the water comes out the bottom.
Leave the pot to stand in the water for 20-30mins.
If the water gets sucked up by the plant, rewater until the pot is completely saturated.
Then dont rewater till the soil is almost completely dry

And I agree with Bish that whatever the problem might be, it certainly looks nothing like an Mg (Magnesium) deficiency.

I have stopped all feed, just watering for now and things seem to not be getting any worse....less leaves drying up now.

Just one question, its nearly 9 weeks flowering which should be long enough but although the lower branches look ready for harvesting the top colas still look like they need another few weeks! No red/brown pistles, all white and fresh looking? Should i wait until the tops look ready?

I have learned that without a jewelers loupe 30 x magnifyer, look for when the hairs are 50-75% brown it is ready and starting to degrade. I would remove the dead leaves and also I may add ,I read recently by a prominent breeder that letting a sativa basicallly die for last 2 weeks makes it mature and finish quicker. Hope this Helps Showgirl

It's the trichomes that you use to tell you how mature it is, not the hairs.

100 lines for you Scribble. Showgirl

i had exactly the same prob with BBcheese.

I considered everything, but boiled it down to poor ventilation or shit genetics.
Although other strains in that environment were fine.

Whats your ventilation like?

Im sure it was due to the genetics of BBuddas unstable afghan cross, that turned out nothing like Original Cheese whatsoever.,, nor any thing like Afghan come to think of it.

Hope yours turns out better
Peace