CAL-MAG question, again......

[Wildfan76]

Strain is northern lights, about 30 days into flower, been feeding cal-mag 2-3 ml per gallon of water, I see no signs of improvement, and the calcium deficiency is creeping up the plant, how worried should I be since I'm just over or about half way to harvest, how bad will it affect the final product? and its just on this plant, the other is just fine, same soil and lights, same water as well, just puzzles me.

[Wannabebotanist23]

Well it's common for leaves to turn yellow when flowering and the rest of your plant looks healthy from this picture, you might not need to worry

[Wildfan76]

think I should stop using the cal mag since its not really doing anything for it?

[Wannabebotanist23]

Yeah I would at this point since your this close to harvest, and since flowering is the end of the plants life I would see no reason for it to want to keep the fan leaves because it's real only job is to make bud to catch the male pollen and make seeds and die, so it would make sense, this is why we should be using hemp for paper, they grow really fast and die every fall, unlike trees

[Wildfan76]

sounds good thanks for the input

[9fingerleafs]

Calcium is a not mobile nutrient. Affected leaves will NOT recover. Check new growth for improvement. If new leaves are fine then all is well. If new leaves have calcium deficiency then it may be a symptom of something else like PH problems

[Wildfan76]

ive been watching soil ph closely, was up around 8, now I have it at about 6.5 and that was a week ago now, still sitting below 7 as of today, I had cut the lower growth early on to increase production at the tops, so as far as new growth there really isn't any to watch, so I'm wondering do I just let it buck and hope it turns out since I'm halfway there to harvest? Like stop giving cal mag?

[Gordo41]

The earlier 8 PH prob had something to do with the problem you have now. Nothing much you can do about it now, just do it right the next time. You're in soil so its not as easy to make changes to the root ball as it would be if you were in coco.

[9fingerleafs]

I think you can give cal mag until the very end if you flush before harvest. It is a matter of how "hard" is your water. Usually soft water with little calcium wil always need calmag. You may think its not doing anything but if you stop you could start the deficiency again hurting your yield. I would advise you to keep it at 3ml/gal the entire grow

[Wildfan76]

sounds good and thanks

[Gordo41]

Yes definitely keep using the cal/mag.

[Wildfan76]

hoping my next crop coming up doesn't run into this situation, not that its the end of the world, but I'm trying to get my system down routine wise. water is at 291 ppm and about 7.5 ph I try to lower ph to around 6, wonder if next time I should leave it?

[Sonnyhad]

I don't see the tell tale signs of rust spots on those yellow leaves. Just take them off and your problem is gone! just keep your ph right and keep an eye on them. There are plenty of us here to help if the problem continues!

[Wildfan76]

actually there are a lot of rust spots I just took a one leaf pic, hard to see I know but they are there, esp under LED you can see them pop

[Sonnyhad]

I had the same thing going one. I don't know why, I just try to correct it and remove the bad leaves. They won't heal.

[Gordo41]

Dont leave it there. Here's a chart showing how PH effects the uptake of nutes by the plant. If you're out of this range you plants cant get what they need.

[Wildfan76]

Will do, if you look closely you can see the spots, and that's on a higher up leaf not a lower one, hence my concern, its further up the plant

[9fingerleafs]

I'd say then its not calcium but potassium

[Wildfan76]

interesting

[NebulaHaze]

Just curious, is only happening to leaves at the bottom of the plant that aren't getting any light anymore? If so, and it's not spreading up the plant, it could just be that the plant is giving up on the bottom ones. That can happen if you've got a really bushy plant. Otherwise I think you're going in the right direction by focusing on the pH!