Rusty seedlings again: help please

[PE636]

Experienced coco grower here. Looks to me like you're not watering/feeding enough. Soak the whole container to runoff, every time, meaning daily at least. Why are you only watering half the pot?
That's hydroponics not soil you've got going on...Is there a reason you are adding calmag? Using RO water or no? I've used Dyna pro in coco under quantum boards and never needed extra calmag.

 

[leafy86]

Experienced coco grower here. Looks to me like you're not watering/feeding enough. Soak the whole container to runoff, every time, meaning daily at least. Why are you only watering half the pot?
That's hydroponics not soil you've got going on...Is there a reason you are adding calmag? Using RO water or no? I've used Dyna pro in coco under quantum boards and never needed extra calmag.

Thought it was calmag def. Watering whole pot now. Gave them 4 litres on Sunday and got 20% runoff. How do you water daily and get runoff? I mean like don't you need wet/ dry cycles And its just tap water left out for a few days

 

[PE636]

Ya. Calmag isn't something you get a deficiency of, it's a product containing nitrogen, calcium, magnesium and usually iron. Dyna Gro has all this. If you are feeding to runoff daily at the appropriate strength there should be plenty available. Underwatering on the other hand, can cause all sorts of apparent deficiencies. Sorry I can't recall how many ml/l I used with Dyna, it wasn't much though. Adding calmag unnecessarily often upsets the balance of elements and just makes things worse.
How do I water daily to runoff? Mine in 3gallon fabric pots, currently each plant get 2.5 liters every day at lights on, and every second day I hit them twice.. Lots of runoff, which collects in a tray and I suck it up with a shop vac.

 

[leafy86]

Ya. Calmag isn't something you get a deficiency of, it's a product containing nitrogen, calcium, magnesium and usually iron. Dyna Gro has all this. If you are feeding to runoff daily at the appropriate strength there should be plenty available. Underwatering on the other hand, can cause all sorts of apparent deficiencies. Sorry I can't recall how many ml/l I used with Dyna, it wasn't much though. Adding calmag unnecessarily often upsets the balance of elements and just makes things worse.
How do I water daily to runoff? Mine in 3gallon fabric pots, currently each plant get 2.5 liters every day at lights on, and every second day I hit them twice.. Lots of runoff, which collects in a tray and I suck it up with a shop vac.

So you don't get a wet/dry cycle no?

 

[PE636]

So you don't get a wet/dry cycle no?

It's going to dry slightly over the course of 24 hours, but no, don't let it dry like you would for soil. Totally different protocol for coco. Some folks, myself included when I have time, water twice daily or even more, especially in flower when they get thirsty.

 

[PE636]

My only other advice is to quit spraying crap on the leaves. Completely unnecessary and just another thing to wonder about if there is any problems.

 

[leafy86]

My only other advice is to quit spraying crap on the leaves. Completely unnecessary and just another thing to wonder about if there is any problems.

I stopped that after the first time lol thanks for your help. Like I said I gave them 4 litres on Sunday so might try giving them more after work till I get runoff.

 

[PE636]

Good idea, this is Tuesday you already missed a day! Good luck!

 

[leafy86]

Good idea, this is Tuesday you already missed a day! Good luck!

Really fed up now got home and boom worse again.

 

[PE636]

Still looking awfully dry. That heater looks pretty close too that's a bit concerning. Definitely water the entire container my friend, soak every bit of coco in there. Dry spots are very bad. Those lower leaves are pretty nearly toast so you'll have to look at newer growth to get an idea what's going on. Probably take a few days to get back on track. I think I was using Dyna gro around half strength, do you have a ppm meter? Should be around 400.

 

[leafy86]

Still looking awfully dry. That heater looks pretty close too that's a bit concerning. Definitely water the entire container my friend, soak every bit of coco in there. Dry spots are very bad. Those lower leaves are pretty nearly toast so you'll have to look at newer growth to get an idea what's going on. Probably take a few days to get back on track. I think I was using Dyna gro around half strength, do you have a ppm meter? Should be around 400.

Heater only comes on when lights off was thinking of moving it. The marks stopped for a few days but looks like summat I done when I watered them on Sunday has done it again. Was white spots on pots like mold fk sake that's not normal is it. Yes have ppm meter but didn't test it on Sunday as its been bang on so far

 

[Preston9mm]

Here's my take....

Everyone will have an opinion about what's causing this.... This is just mine.


Every symptom you are seeing points to overwatering. Some symptoms may point elsewhere, but still, ALL of them are symptoms of overwatering...

There is a famous myth that you cannot overwater in coco.... this is 100% false. You may not kill it, but you will see slow/sluggish growth through early veg.... as you have.

This is a game-ender for autos... they have a limited veg window, you either hit it, or ya don't.

At the end of the day... A plant will pray at the lights before it starts drooping from being dry. If they droop from day 1.... you're over-loving them

 

[PE636]

I'd agree with @Preston9mm but for the fact the plants are still growing half decent and the leaves don't look to be curled and puffy as overwatering likes to present. I think if they have been over watered this long they'd be in a lot worse shape. I guess time will tell. OP may have to do an experiment and hopefully let us know the results!

 

[PE636]

How old are they now?

 

[leafy86]

How old are they now?

25 days. 3 have been topped aswell.

 

[PE636]

I've also found you can over water coco in "large for the plant" container if you soak it and leave it too long. Oxygen gets used up before it drys. My solution is to water again thus introducing another batch of fresh nutes and oxygen.. Works for me, YMMV. I'm sure you're not letting them sit in runoff or anything silly.
Well for 25 days they are a bit slow maybe but not terrible considering.

 

[PE636]

Ah I see your racks and runoff trays there now, carry on.

 

[leafy86]

Ah I see your racks and runoff trays there now, carry on.

I've seen boys transplanting autos if you know what your doing but don't think ild risk it myself. These atm are stardawg autos same I done last time and only took 10 weeks aswell. Last grow was also messed up only 200g off the 4

 

[PE636]

I haven't done anything auto so can't speak to that. Common sense tells me a gentle transplant at the right time would be fine though.

 

[d42zero]

Il post one when I'm home. Still a bit of rust coming on one of them all in looking good though. I do autoflowers so I don't transplant.

The article I linked you to specifically states they transplant autos and gives their reasons for it, I glossed over that bit since I grow PPs but the gist I got is there's no reason not to transplant autos.

So you don't get a wet/dry cycle no?

I'm feeding four times a day.... no dry cycle. Think of coco like your res on a DWC.... it just holds the nutrient solution near the roots so they can get to it, that's all. You wouldn't let your DWC res go dry for the same reasons you don't let coco go dry. You don't even let soil go dry... you just let the top little bit go dry, but water drains slowly through soil so when the top inch is dry it means the rest is about ready for water. Coco drains way more quickly so if the top inch is dry, the rest is well overdue for water.

25 days. 3 have been topped aswell.

To give you some comparison, the photo I posted was 43 days from seed (including germination time) and they have been HEAVILY topped twice.