Slow growth - Is it temperature?

Hey guys and gals...

I've decided to transcribe my grow journal onto RIU. I'm not satisfied with the growth of my plants. Most are on their fourth set of leaves, but have just kinda stopped... they have a complete third set of leaves but have stopped growing vertically or making new leaves. I would like to get to a point where I can clone them and sex them, but I need them to get much taller. They are in 3" pots.

I had pH issues earlier with nutrient lockout. I have corrected that problem by pHing every time. I don't know if it is because the last couple times I went feed-feed-water-feed-water-feed for the last several waterings. I was afraid of nutrient burn when one of the plants leaves browned a bit, but I plan on getting back to a feed-feed-water rotation.

I give all the details and pictures in my grow journal. My question is 1) is it just these freak low temperatures I have been getting at night and maybe low humidity, or 2) are my plants potentially getting root bound at week 5 even though they haven't gotten very big, or 3) something else I'm missing. If you need any other data, please let me know and I will get it.



Week 5, Day 33 - they just don't look very happy

How often are you watering? how much? what kind? temp? o2? exactly what are you putting in it? and what ph?

watering daily can be touchy. Especially with little plants. Coco can be finicky with nutrients as well. as I have noticed atleast. I wish it was as easy as 6/9 once a day (;

I put all the info in my grow journal which I linked to. I'm watering every two to three days, tap water, rested for 24 hours to vent chlorine, so room temperature.

I'm thinking it's root bound because that is the only thing I see that matches the symptoms. I'm gonna transfer today.

I hope u get them back to being healthy cause they looking ugly as hell right now. Sometimes....too much attention can do more harm.

i highly doubt they are root bound. seems too be a ph problem. my tap is 8.0 and i gave that too two seedlings c i was unprepared too water. the next day they looked exactly the same.

Ya, they look like pH issues to me, but I calibrate and pH the water every time now. I'm gonna transplant and feed and pH again. Gonna pH the run off a well.

Did you flush the coco before planting? If not, it could be salt residue in your medium.

I might not have flushed the coco properly. I did buy a quality product from a hydroponics store. I transferred the plants today into 6 inch pots from 3 inch ones, pHed to 6.0 with 1/4 nutrients. The roots looked good. I'll have to read up on the coco coir, see if there is a solution/test for salt. I tend to pace myself with corrections... I will wait at least 2 days after a major change, like this transfer to larger pots, because I new growers tend to overdo rather than under do anything.

I do think I'm going to get a TPS meter to test the runoff to see if its too high. I'm following a AskEd's write up at grasscity.com, and if the salt is too high, then a good flush should get me back. I should probably schedule a flush this week anyway, since he recommended doing a flush every 4 weeks.

Thank you everyone for your help. You don't know how valuable it is to "think out loud" and bounce ideas off of you guys.

I would tend to think a flush will fix you up dude. I use coco too and I always flush the shit out of it because I burned all of my plants once and I don't want to go through that again. I use good coco from a hydro store too but it may still contain salt

Its not pH... And flushing is the worst advice I think anyone could ever give for this problem. It's over watering, i'm surprised nobody else mentioned this because its quite obvious.

Duude, what ru using to check your ph? Pen or liquid? Also looks like you don't have any pearly lite.. I use a 50/40 coco pearly lite mix and she loves it

Im thinking you have a couple issues. 1st issue is the coco probably was not flushed thoroughly. Not sure what you are using for coco? But i use the botanicare blocks and gh blocks. They used to flush the botanicare much better than they do now. Im hydro and have not used coco since last feb. I had no issues at all last year when i just added 5 gallons of water to my coco blocks and charged them with cal mag. This year, much different. I prepared the same way and my plants did not look lush green. I know it was the coco because i have four different strains going, all being fed water only till they get some legs, and they all have same symptoms. Its hard to over water coco even if there is no perlite. If you are watering every couple days that should be good if the soil is in fact drying up. Your roots look white so i dont think you are overwatering. I think the problem also worsens when the roots start to dry up in the salt of coco. 2nd issue you are having is root bound. Those yellowing leaves on bottom are usually sign of root bound. You have them transplanted so i would Flush them out with phd water (6.0) and wait till they almost start to wilt before feeding again with 1/4 nutes. they should come back nicely within a week.

I'm using a digital pen pH meter. I transplanted them into 6 inch pots and they seem to be doing ok. I talked with some local people and I just upped the nutes to 1/2 feed to see if they respond. The leaves were "tacoing" a bit, and the more I read up, the more it looks like they weren't getting enough food (i.e. Mg deficiency), hence the increase in nutes. I will monitor for a couple days and won't water again till they feel almost completely dry. I'm actually going to be hooking up my Arduino microcontroller soon that will give me very accurate data on soil moisture levels, temperature, and relative humidity.

I'm using the Botanicare Coco Coir bricks, expanded with plain water. I'm pretty sure I'm not over watering (i.e. roots looked healthy when I transplanted, coco is pretty hard to over water, I'm only watering every 2-3 days and just till I get a little bit of run off), I went and got a TPS meter and my tap water was actually pretty clean, only about 100ppm, but I have switched over to distilled water anyway. I have tested the runoff and the ppm were good, only a couple hundred ppm, and I tested fresh coco coir that I haven't planted in yet, and it too was good (less than 50ppm). I pHed the final 1/2 feed solution to 5.9 and it came out at 175ppm. I'm thinking I may have just been starving the little guys... I'll come back in 3-4 days and let you know.

I did not read this whole article so its possible I overlooked, but in 3" pots which I start my seeds out in (mine are square tho) I typically give a transplant after second set of true leaves, and all the roots will already be at the bottom and sides at that point, by the looks of things its not a ph or nute problem its needing more root space, cannabis roots grow very very quick, and I have found on average its safe to say a gallon of soil per week of veg is what the roots will grow into, some a tad faster or slower but thats my avg way of figuring out when the roots will be grown throughout the pot.

Schwagstock said:

I did not read this whole article so its possible I overlooked, but in 3" pots which I start my seeds out in (mine are square tho) I typically give a transplant after second set of true leaves, and all the roots will already be at the bottom and sides at that point, by the looks of things its not a ph or nute problem its needing more root space, cannabis roots grow very very quick, and I have found on average its safe to say a gallon of soil per week of veg is what the roots will grow into, some a tad faster or slower but thats my avg way of figuring out when the roots will be grown throughout the pot.

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I had a feeling I might not have been transplanting them fast enough. Here they are 12 hours after I watered them with 1/2 feed (up from 1/4) at 5.9 pH. Color is coming back... and some of them seem to be going onto their 4th set of fan leaves now... again, I've made a couple corrections and I'm going to wait and see what happens. I won't touch them again until the coco is almost dry.

The plants are starving because your to tentative with the nutes. You need hydro nutes for coco, every watering at full strength ASAP.

*BUDS said:

The plants are starving because your to tentative with the nutes. You need hydro nutes for coco, every watering at full strength ASAP.

Click to expand...

You were completely right... upon further analysis they were only getting about 1/10th of the nutes that they needed each feeding. Feeling pretty noobish... my error has been corrected (full strength general organics feed schedule, week 3 regimen).

I'm face palming myself over this... stupid, stupid, stupid.

24 hours later I could swear they have shot up at least an inch... stupid stupid stupid... oh well, at least none of them died and I think they are going to bounce back nicely. Just hope I didn't cause them too much stress.