Same problem in all my grows

Hi guys,
Been growing autos for nearly a year now and I've noticed all my plants seem to show the same problem - Some sort of rusty-looking markings on the leaves. After enough times, the leaves start to go crispy and die off. Plants always grow to maturity and end up smoking well, but I'm wondering if this could be also stunting my plants' growth and reducing yields? Plants are 17 days old, and I'm growing in plagron lightmix with about 50% perlite, watering using GH Flora Tripart at half-strength, rinsing with 60ppm water after every 2 feedings. I also make sure my feeding/rinsing water is always at 6.5 PH with a solution testing kit. Can anyone point me in the right direction please? I'd love to have a few plants grow healthily from start to finish. Thanks

Kalel01 said:

Hi guys,
Been growing autos for nearly a year now and I've noticed all my plants seem to show the same problem - Some sort of rusty-looking markings on the leaves. After enough times, the leaves start to go crispy and die off. Plants always grow to maturity and end up smoking well, but I'm wondering if this could be also stunting my plants' growth and reducing yields? Plants are 17 days old, and I'm growing in plagron lightmix with about 50% perlite, watering using GH Flora Tripart at half-strength, rinsing with 60ppm water after every 2 feedings. I also make sure my feeding/rinsing water is always at 6.5 PH with a solution testing kit. Can anyone point me in the right direction please? I'd love to have a few plants grow healthily from start to finish. Thanks

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How big are the pots, how often you water and how much water do you give them at a time?

Irregular rust spots is almost always Calcium deficiency. If it is more consistently the margins and tips with regular spotting (consistent pattern in veins) then more likely Potassium.


Always start with basics:
1. plants cant take any nutrients if PH is off - depending on your medium but usually 5.5-6.5 (6.2 sweet spot)
2. Check WHERE the damage is occurring (new growth or old growth or both, leaf edges or between veins, check stem coloring, and undersides )
3. Check WHAT the damage looks like (spotting, rusting, curling, etc)
4. Google "Cannabis deficiency chart" and compare #2 & #3

Ph / lockout issues. What is rinse water? So you feed it then chase it with water like a shot of cheap whisky? Feed to run off and dont chase it with mini flushes.
ive never had to feed that soon in soil but guess it’s possible . You should be watering thoroughly and the let dry before watering again. 17 days old and watering after every two feedings? How many times have you fed that? Try water water feed.I suspect your over feeding

It could be alot of things. Need more details and pics of whole plants. It could be light stress, overwatering, lockout, deficiency or multiple things going on at once. The plant looks sad. Leaves should never be hanging that low that its touching the soil. Learn to read plant behavior. Leaves pray when happy.

Thanks for your replies. Some further info:
Plants are in 10l pots, I usually water when they feel light, first 2 inches are pretty dry at that point. I water until I get about 200ml of runoff.
I've been adding GH calcium magnesium at 1ml/l to my feeding solution.
Rinsing with clean water right after feeding doesn't really make sense bam0813, to clarify I water with my nutrients mixed in when the plants need watering, then the next time they need watering I water with nutrients mixed in, but the time after that I'll just water with RO water pH'd at 6.5. Isn't this standard procedure for synthetic nutrients?
Plants were praying all through the grow until I performed topped and LST'd yesterday, could be they are still stressed.

No i doesnt but thats how it read to me. Actually rinsing makes no sense either but.Ive never heard of feed feed water in soil . Why not use tap and forget about calmag? Seems your stripping it out to buy it back. Btw RO is already 6-6.5 water water feed is typical of soil imo

Also depends on age size. My plants get watered every day at this point . So i dont feed every third day.

Kalel01 said:

performed topped and LST'd yesterday, could be they are still stressed.

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No that's not from lst stress. Looks like classic overwatering. U can feed once or twice a week but never 2 feedings back to back unless in coco. No rinsing/flushing. U might be flushing your nutes out. Only use calmag if or when the plant shows signs it needs it or u are creating a problem. It will lock out other nutes which should be in your Gh. Reduce light, whenever there is an issue to help her recover better. Blasting sick plants makes it worse. They really don't need much early on anyway. Dont water til pot it super light so your roots can breath. Pay attention to the leaves posture. It can also tell u when to water. When they're praying don't water til they give slight droop. Hopefully this can get u off to a better start and it all may work its self out. All we really do is feed nutes, water, give light(indoors) and protect from pests. Once u can read/understand what plant is communicating, all u do is keep her happy.

Kalel01 said:

plagron lightmix with about 50% perlite, watering using GH Flora Tripart at half-strength,

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Hello,
I'm used to running a very similar setup. Canna Terra Pro + 50% perlite, 1.8 EC, pH 6.0, DTW to10% pot volume, feeding once a day, up to a maximum of twice per day.
Using 18L pots.

Kalel01 said:

Plants are in 10l pots, I water until I get about 200ml of runoff, rinsing with 60ppm water after every 2 feedings.

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In my own opinion this is where you're going wrong. I personally run to 10% pot volume in waste, and never need any rinses between.
So 10L pot, you should be seeing about 1L in waste. 200mL isn't enough.

Kalel01 said:

I usually water when they feel light, first 2 inches are pretty dry at that point.

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Sounds like they're maybe getting a bit dry too?
As I said using 18L pots with 50/50 CannaTerra to perlite, feeding once per day. Maximum of two.

Kalel01 said:

Thanks for your replies. Some further info:
Plants are in 10l pots, I usually water when they feel light, first 2 inches are pretty dry at that point. I water until I get about 200ml of runoff.
I've been adding GH calcium magnesium at 1ml/l to my feeding solution.
Rinsing with clean water right after feeding doesn't really make sense bam0813, to clarify I water with my nutrients mixed in when the plants need watering, then the next time they need watering I water with nutrients mixed in, but the time after that I'll just water with RO water pH'd at 6.5. Isn't this standard procedure for synthetic nutrients?
Plants were praying all through the grow until I performed topped and LST'd yesterday, could be they are still stressed.

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That damage is from pH fluctuations. Usually when the soil gets too dry then is completely saturated.

It most likely won’t progress as you water more often as the plant grows

Way to much perlite. I too thought more means better. The roots hated it. While transplanting em noticed they looked kinda tangled up in it. 20-30% is more then enuff. Some plants are finicky so if they don't like it they will let u know.

The Overwatering in Promix creates skinny MacDonalds roots. They need oxygen as much as water to have big fat healthy roots. Just my opinion.but I would pick up my pots before I water them. Promix weighs next to nothing when dry. I've grown in straight perlite so doubt that's issue.

Southernontariogrower said:

I've grown in straight perlite so doubt that's issue.

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So u grew hydroponic and perlite held your plant up at the base? Thats a bit different.

Kalel01 said:

Thanks for your replies. Some further info:
Plants are in 10l pots, I usually water when they feel light, first 2 inches are pretty dry at that point. I water until I get about 200ml of runoff.
I've been adding GH calcium magnesium at 1ml/l to my feeding solution.
Rinsing with clean water right after feeding doesn't really make sense bam0813, to clarify I water with my nutrients mixed in when the plants need watering, then the next time they need watering I water with nutrients mixed in, but the time after that I'll just water with RO water pH'd at 6.5. Isn't this standard procedure for synthetic nutrients?
Plants were praying all through the grow until I performed topped and LST'd yesterday, could be they are still stressed.

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So roughly 4ml per gallon of Ca/Mg? That seems high to me. I add 1-2ml per gallon to water that's been filtered down to 0ppm...then whatever is included in my nutrients.