Still learning - this is my 3rd grow. 6 plants, 3 strains - all autos
Tropical conditions. Temp 26° - 30° (78 to 86)
Humidity 70%
Light tent - Mars Hydro TS 300 x 3 - 18/6
Soil mix - coir-perlite-guano-worm cast/bonemeal
Seedlings started in an isolated pocket of potting soil
CALMAG + Voodoo Juice added to all in 3rd week
Water @ 6pH
Advanced Nutrients Micro @ ¼strength added at end of 4th week
Current soil EC at 0.3
Now in the 5th week
Four out of 6 are doing fine - have started LST - pegging horizontally around the pot
BUT 2 were started one week after the others (2 of the first set didn’t germinate) These two are growing stunted - very pale green and lower leaves bleaching
These 2 grew stunted from the start and are now as you see them.
Anyone identify what the cause might be and also how to fix it?
(#3 is what the others are doing - the same seed batch as #2)
ps - seedlings in big pots means that I’ve only been watering them every 3 days - about ½pint (250 ccs) at a time to start with. In their 3rd week it upped to 1 pint every 3 days. The photos show them just after they were watered.
When I have used advanced nutrients ,I have always used together and adjusted ratio according to growth stage.
Always add micro to water first then grow ,then bloom.
You are in coco?
Did you buffer coco?
You have to take what you get with autos. You’ll occasionally get a runt or 2.
I see you are feeding Voodoo Juice and a micro product. Voodoo is a microbe product and AN Micro only contains micronutrients like iron, copper, boron, and manganese. Are you also feeding a product that contains nitrogen, phosphorous, and potassium? A lack of nitrogen will definitely cause pale, yellow leaves.
Sorry fellas - AN Micro and Grow used together, for the first added nutes last week at ¼ strength. The coco was washed twice and allowed to dry beforehand.
(It’s quite possible that the high temp and humidity has caused this - on my last grow I had a Dieselmatic which seemed to go native and revert to its ancestry, suddnly growing way long and skinny before it bloomed - it seemed to go photo too, not flowering until it got 12/12.)
Thinking back - I didn’t need to use Voodoo juice, as the soil is already rich enough - maybe that was simply too much for the younger pair at 3 weeks . . . ?
My first thought was nitrogen starvation, but after using AR nutes 4 or 5 days back, there’s been no improvement . . . . still puzzled . . . maybe I should try upping it to ½ strength?
Autos do their own thing, at their own time. Check the runoff before adding. I think coco coir needs ph of 5.5 to 5.8. I don’t grow autos or use coco, so I am probably discombobulated. Anyhoo, good luck
Hey Rob, most brands of Coco need to be buffered with a good dose of Calmag after expanding and rinsing. If this isn’t done then the Coco consumes all the Calcium and Magnesium before the roots can take any up. Have a look at a site called cocoforcannabis for a detailed explanation.
MidWestGuy -
Being small plants in 5 gal pots, I’ve never yet soaked the soil until run-off. I’ll let em dry out then water fully and check the run-off.
I don’t think a 30% blend would need the calmag added first. But that is a common practice to pre calmag the coco. I think those 2 plants just need a tad more nitrogen. It is all the growth affected, not just new or older growth. To me that seems to point to nitrogen. I second the “up it to half dose from 1/4 dose.” You may even want to lower the ph a tad on those two too like @beachglass suggested. Just a couple more drops of ph down. You will probably need to make nutrients for the happy ones, then redo the mix for the late bloomers.
This is another case of coir used in potting soil instead of peat moss because of location. I been noticing a pattern about that related to geography. Anyway its a soil mix and coir is something like peat moss, not totally, I never used it though or even seen it. I’d approach that like soil
I don’t think a 30% blend would need the calmag added first. But that is a common practice to pre calmag the coco. I think those 2 plants just need a tad more nitrogen. It is all the growth affected, not just new or older growth. To me that seems to point to nitrogen. I second the “up it to half dose from 1/4 dose.” You may even want to lower the ph a tad on those two too like @beachglass suggested. Just a couple more drops of ph down. You will probably need to make nutrients for the happy ones, then redo the mix for the late bloomers.
. . . . . . . . . .
Thanks for the detailed reply - and for making me realise that it IS all-over-pale, pointing to nitrogen starvation.
They’re due for a feed today, so I’ll try a boosted dose (½-strength) of nutes and wait for something to happen!
This is another case of coir used in potting soil instead of peat moss because of location. I been noticing a pattern about that related to geography. Anyway its a soil mix and coir is something like peat moss, not totally, I never used it though or even seen it. I’d approach that like soil
. . . . . . . . . .
I’m in Thailand - there are dozens of sellers with uncompressed 100-litre (etc) bags of washed/prepped coir (although very few selling compressed blocks) - the Thai postal system is extremely efficient and very cheap (about $3 to send 100 Ltrs of coir from one end of the nation to the other.)
It also turns out that peat moss is over double the price of coir . . . so I have avoided using it. But I now realise that for a few $$ more I can sidestep any probs/hassles from using coir - although all the other plants are doing fine.
Coir isnt problematic, I dont think one is better than the other. One holds more water than the other. So when you know your watering routine its good.
Lots of organic matter in your soil. Hard to believe its deficient in anything with small young plants.
Jaysittinback Coir isnt problematic, I dont think one is better than the other. One holds more water than the other. So when you know your watering routine its good. Lots of organic matter in your soil. Hard to believe its deficient in anything with small young plants.
. . . . . . . . .
The seeds were germinated in fibre plugs - on their 2nd set of leaves they went into 4 gal pots filled with the main soil-mix - BUT I scooped out an isolated pocket of ordinary potting compost to isolate them from the rich soil mix.
There was no real consistency in the way I did this, and I’m now thinking that perhaps these two seedlings might be sitting in bigger pockets of ‘neutral’ soil than the rest.
But that doesn’t really explain it, as I don’t think the seedlings really miss all those nutes in the first three weeks . . .
3 weeks’ roots can fill a couple gallons.
Agreed with above, not uptaking enough nitrogen. With guano and other crap in there it should be there. I say get pH in range for soil.
What season is it there? Just outta curiosity. I see your temps are exactly where our mid-summer will be
