Rusty dirty looking leaves? What is this?

[Jslo313]

Heyya folks, been seeing more and more of this lately, these rusty lookin leaves. Trying to figure out what it is. Been affecting the Outter most leaves, mainly the ones furthest from or hidden from the light but now seems to be happening more and more. Pulled the first few off as they were small and didn’t seem all that important but I’m starting to get worried. About four weeks into flower, give or take, indoor grow. Temp and humidity well controlled. Any ideas as to possible causes? Been looking for signs of pest and can’t find any. Nutrients have been very minimal but haven’t cal/mags anything. I use a third tap water mixed with distilled to get some of the micros in there. Not much of a science, just know there’s some calcium in the water. Lol. What gives? Any ideas or possibilities? Or am I overlooking something terribly obvious?

 

[steamroller]

I'd be looking for thrips.
Then decide if you want to kill them or try to just finish.
Spinosad kills them read up if I am right.

 

[Jslo313]

Thanks for the tip. Might pick up some spino at the store just in case, but I’m not seeing any of the signs I’m reading about and I’ve checked the bottoms of almost every leaf to show the sign. No pests, even under magnification. No holes in the leaves, nothin. Maybe a decent clue is that it all seems to emulate from the veins of the leaf. Gonna keep on reading but please keep the ideas coming. Not gonna count out thrips but def wanna know what other possibilities are out there. My first time growing so wanna try and make sure I get it right!

 

[Jslo313]

anyone else think maybe it's just a cal/mag defficiency? been perfectly PH'ing my water to 6.5 but haven't tested runoff in well over a month. when I did, it was pretty low but I really didn't know what to do about it. lol. maybe hit it with some 7.0 water, and test runoff?

 

[BigBlonde]

Well... I don't know. I agree that it seems to emulate from the veins. I was wondering if you could get a magnified picture of the spots. I'm curious if the discoloration is on the leaves or a change to the color of the leaves themselves.

 

[elusiveshame]

Looks like a deficiency. A dose of calmag wouldn’t hurt. Just remember that those spots won’t magically turn back to normal, so at this point you want to keep it from worsening.

You’re a few weeks early for it to be the normal life cycle IMO, and it could be a nutrient lockout, but if you haven’t been feeding it much, I’d say it’s likely a lack of nutrients.

It’s definitely not water 😅

 

[growsince79]

Heyya folks, been seeing more and more of this lately, these rusty lookin leaves. Trying to figure out what it is. Been affecting the Outter most leaves, mainly the ones furthest from or hidden from the light but now seems to be happening more and more. Pulled the first few off as they were small and didn’t seem all that important but I’m starting to get worried. About four weeks into flower, give or take, indoor grow. Temp and humidity well controlled. Any ideas as to possible causes? Been looking for signs of pest and can’t find any. Nutrients have been very minimal but haven’t cal/mags anything. I use a third tap water mixed with distilled to get some of the micros in there. Not much of a science, just know there’s some calcium in the water. Lol. What gives? Any ideas or possibilities? Or am I overlooking something terribly obvious?

Check for mites.

 

[Jslo313]

Yup, up at wal mart hoping to find some cal mag. I’ll take some right up close pics as soon as I get home. Doesn’t seem to be ON the leaves. Tried to rub it away after reading about rust fungus. Thankfully not rubbing off.

 

[Jslo313]

Here’s some up n close pics.

By the by, not water? They look overwatered?! Damn! I’m down to once every five days. Thought I’d course corrected by noobie-ism. Lol. Tonight was watering night. Had to order cal mag from Amazon. Will be in tomorrow night sometime before bedtime. Guess I can make it one more night.

Well... I don't know. I agree that it seems to emulate from the veins. I was wondering if you could get a magnified picture of the spots. I'm curious if the discoloration is on the leaves or a change to the color of the leaves themselves.

 

[elusiveshame]

The water comment was a joke from another thread. Disregard that.

It looks like you’re using self watering pots? Are you top watering or solely relying on bottom feeding? 5 days seems like a long time for bottom feeding.

 

[Jslo313]

Nah, lol. The bottom feeders seemed like a good idea before I started growing. Now they’re just expensive water trays. Need to just throw the wicks away. Not really seeing a point in those anymore.

 

[GreenGalaxyFarm]

Was thinking cal defici when first seen

 

[Mothman]

Was thinking cal defici when first seen

Me too. Or thrips. I’m betting Ca def.

 

[Homesteader]

Overall health is not good. Multiple issues that probably all start with mites. No visible tricomes in flower is another sign something is amuck. I am not positive on the rust spots but they do not look like calcium to me and could just be due to the mites sucking the life out of the plant.
You can tell in your third picture of the leaves. Could be thrips but Im thinking mites. Check under the leaves

 

[Ballisticsuk]

anyone else think maybe it's just a cal/mag defficiency? been perfectly PH'ing my water to 6.5 but haven't tested runoff in well over a month. when I did, it was pretty low but I really didn't know what to do about it. lol. maybe hit it with some 7.0 water, and test runoff?

It looks like calcium deficiency
Do you use led lights
If so move them up a bit flush the medium and then add 0.2ec of calcium it doesn't look mag deficient so I wouldn't add any of that because the issues off the back of mag toxicity is apretty bad situation


You can also foliar feed calcium for faster absorption

 

[Ballisticsuk]

It looks like calcium deficiency
Do you use led lights
If so move them up a bit flush the medium and then add 0.2ec of calcium it doesn't look mag deficient so I wouldn't add any of that because the issues off the back of mag toxicity is apretty bad situation


You can also foliar feed calcium for faster absorption

Clcium up takes best around 6.0 6.1 pH level so if your run off is lower consistently then there is your problem flush with pH 7.neat water Untill you have passed 3-4 times the size of your pot and the run off is coming out around 5.9. Then resume feeding with a lower ec and 6.5 pH

Mag absorbs best at the lower end of the spectrum 5.5 5.6

Explains why only calcium is locking out

 

[Ballisticsuk]

Looks like a deficiency. A dose of calmag wouldn’t hurt. Just remember that those spots won’t magically turn back to normal, so at this point you want to keep it from worsening.

You’re a few weeks early for it to be the normal life cycle IMO, and it could be a nutrient lockout, but if you haven’t been feeding it much, I’d say it’s likely a lack of nutrients.

It’s definitely not water 😅

Has it been flushed ever
Even min nutes without flushes cause problems

 

[steamroller]

Look on back/ bottom of leaves.

 

[BigBlonde]

Look on back/ bottom of leaves.

That would be helpful. When I had a problem with spider mites, I would cut off a fan leaf and look at the bottom under one of those $30 microscopes from Amazon. A good jeweler's loupe works well for that purpose, as well. Cutting off the leaf made it much easier to see if there were any critters living there.

 

[steamroller]

Thrips or mites should be easy to see.
IMO if it was spider mites webs would be seen/found somewhere.
It could be a Ca def but it seems extreme if it is IMO. 🤷‍♂️
The plants need for Ca is highest in first 4 weeks of flower I believe so not ruled out completely.