Sugar leaf deficiency in flowering

[Delty]

Problem: Deficiency/rusting showing on sugar leaves (2 colas only) during flowering

Medium/grow method: Canna Coco Coir+ 10% perlite.

Feed: and supplements used: Canna Coco A&B, PK13/14 to 1.0EC above base PH @ 5.6-5.9. Canna Boost, cannazym, rhiztonic

water source: 0.1EC rain water

Strain/age: Seedstockers Thin Mint Crack Auto, 11 weeks from sprout

light used: Mars Hydro SP150

Climate: 23C 55% humidity

Additional info: The buds are still growing well and though it's quite progressed, there are still some white pistils needing to turn brown. The plant is otherwise very healthy looking and this is affecting two colas only. I don't think it's light/heat stress but these two are nearest the light at around 12" distance. I am also growing a Seedstockers CBG Auto and a Purple Punch and Sweet Seeds Sweet Gelato in the same room/conditions/feed and they are all doing excellent, though appreciate mixing a separate feed for fertigating this one will be needed if we think it's nutrient related? Most of the plants have handled/responded well to the little pk13.14 ive been giving them (0.2EC of the 1.0EC total), so could cut that out again if needed.

Appreciate any thoughts, thank you.

 

[Heavily Medicated]

I had a similar thing several years ago that I tracked down to Boron deficiency. It did not seem to effect much that late in the grow. Probably not enough time left to fix any problems. I do think it had something to do with the lights being too close. I had this when I first started with LED lights and think I may have been too close. If you can, raise your lights a little or move her so she is not directly under the lights, and see if it continues. I try to keep 18 inches clearance from top of bud to my LED.

 

[Mañ'O'Green]

@Delty The plants overall look ok but that flower may be showing signs of some color change. It is hard to say if it is fade or nutrients? In any event the P-K boost is just for a couple of days don't over do it.
Carry on

 

[MrAutoGrower]

The looks to be too much nitrogen in my opinion. I had this issue once with one of my big girls. She was 5ft and produced around 7oz. Im going with nitrogen based on the colour of the leaves, the droopin on them, and the shape of the buds. The plant is still in good shape though, just cut back on the nitrogen/ppms. I overfed a smaller plant too much nitrogen, and when too much nitrogen is involved you can end up with fluffy buds and skinnier ones. Still looks like a decent plant though. Cut back the nitrogen and feed P amen K. More P to help with density