Why are they growing slowly?

I've narrowed it down to three things that may be affecting the plants growth. Temperature, soil medium, OR the grow light. I cannot rule out the growlight as I have not done any light testing with one of those 'metres' you guys all use.

There are a plethora of wood chips inside of my soil that I did not sieve before use (noted for next time). My day time temps in the afternoon reach temps as high as 34 degrees Celsius (that was the highest, not the average. Average temps are usually 31C and 32C by about 4pm-6pm. But notice how the one plant seems to be growing at a faster rate than the other three? This is the biggest enigma out of everything. The other three have similar to average amounts of foliage, whereas this one plant is almost two inches taller or more than the others.

I really do feel like the combination of wood chips in the soil and high temps are affecting the rate of growth. What do you think? I transplanted on July 5th and gave them the first fertilizing and watering on July 11th. They have not been watered since (and won't be watered until they begin to wilt). I'm trying to build my roots up and I do not think I pushed them hard enough as seedlings, I believe I overwatered while in the first pot.

The first plant is the plant that's growing faster than the other three and the second plant is the one that's showing signs of slowest growth.

The wood chips won't cause much of an issue bar lowering the pH as it breaks down, and leeching a small amount of nitrogen from the medium as chips have a large carbon composition. They look pretty happy though.

Usually high temps will manifest as longer internode length at first before stress is showing (the plant wants to increase airflow), but low 30s isn't too bad under LED. You can counteract the higher temps by running slightly higher humidity.

Regardless, there will always be differences in phenotypic expression even in the same environment unless they are all clones off the same plant.

How old are they? If they are only a few weeks old they don't look too bad. On another note, waiting until a plant wilts before watering is not the best idea. Generally understanding the weight of the pot, the plants body language and the plants uptake and needs is more reliable than waiting for symptoms of stress to show.

Letting a medium dry out too much will create pH and salt ratio swings and increase the possibility of hydrophobic patches in the medium, bit I don't think your near that point anyway. Just worth a mention.

VincenzioVonHook said:

The wood chips won't cause much of an issue bar lowering the pH as it breaks down, and leeching a small amount of nitrogen from the medium as chips have a large carbon composition. They look pretty happy though.

Usually high temps will manifest as longer internode length at first before stress is showing (the plant wants to increase airflow), but low 30s isn't too bad under LED. You can counteract the higher temps by running slightly higher humidity.

Regardless, there will always be differences in phenotypic expression even in the same environment unless they are all clones off the same plant.

How old are they? If they are only a few weeks old they don't look too bad. On another note, waiting until a plant wilts before watering is not the best idea. Generally understanding the weight of the pot, the plants body language and the plants uptake and needs is more reliable than waiting for symptoms of stress to show.

Letting a medium dry out too much will create pH and salt ratio swings and increase the possibility of hydrophobic patches in the medium.

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They sprouted from the soil on May 23rd (I germinated in a cup of water). They were in the 4.00 round pots for over a month and I watered them daily, sometimes TWICE daily.

Those are 5 gallon grow bags they're inside of now. So I have technically been growing for two months now. First grow, I'm not upset over the lack of progress being made. It's a learning experience. But I do think I've done SOMETHING wrong, and I also think when compared to other photos posted on this site, that my plants are growing 'slowly.' What do you think? Am I right to feel this way?

As a rough estimate I would have said four weeks, so they're is definately something slowing them down, bad I'd say it was the rate of watering in the Initial pots.

Overwatering usually comes from too frequent application over too much volume, so it sounds about right. I normally remove mine from the 4" pots around day 14. Usually I've filled a 4" pot with roots by day 14.

This was the last one at day 25 or 26 (purple punch/Durban poison auto) and it was regularly hitting 32-33 daily, so heat inst too big of an issue of your VPD is in range.

Current two at day 16 and 13 respectively. Getting slow growth this time due to 50-68f tent temps.


You've done better than a lot first time round, so I wouldn't be pissed either. They will drastically increase in size once flipped.

They look healthy. I would off rip assume light intensity is low. What are you using on them? At what distance? Drop That light to 12-14 inches for a week and flip. 2 months is a long time, your getting close to a month behind your next harvest babysitting this 1

Try adding one of these

VincenzioVonHook said:

You've done better than a lot first time round, so I wouldn't be pissed either. They will drastically increase in size once flipped.

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I've taken that 'kiss' principle you guys advocate so heavily to heart. Seriously, some of the things I read on this forum make my head spin. I would not have used any nutrients if I could have.

ProPheT 216 said:

They look healthy. I would off rip assume light intensity is low. What are you using on them? At what distance? Drop That light to 12-14 inches for a week and flip. 2 months is a long time, your getting close to a month behind your next harvest babysitting this 1

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I have the light 25" from the plant with the least amount of growth. It's about 23" from the plant with the most growth. Light is a MarsHydroTSL2000 at 75% intensity.

You think if I put the light down to 12-14 inches they'll be ready to flip to flower? (that is flip means, right?)

Drop it down to 16 inches and max out the power. They will b so happy

T

bobj1598 said:

I've taken that 'kiss' principle you guys advocate so heavily to heart. Seriously, some of the things I read on this forum make my head spin. I would not have used any nutrients if I could have.

I have the light 25" from the plant with the least amount of growth. It's about 23" from the plant with the most growth. Light is a MarsHydroTSL2000 at 75% intensity.

You think if I put the light down to 12-14 inches they'll be ready to flip to flower? (that is flip means, right?)

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Just watch out, a TSL at 12" will be something close to 1500umol/s in the hot spot.

ProPheT 216 said:

Drop it down to 16 inches and max out the power. They will b so happy

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Agree. 16" would be around 1000umol/s (DLI 43) in the hotspot and an average of roughly 700-800 over the majority of the tent.

I am going to drop the light down to 16" and up the intensity to 100%. I will report back here in 48 hours

Are they mirrors on the wall or am i smoking too much reefer

BenGman said:

Are they mirrors on the wall or am i smoking too much reefer

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Close, the walls have mylar film stapled to them. It was the cheapest option available at the moment

Oh sweet!! Was gonna say lol but yeah Your biggest mission is to get temps to 28c no higher my man, specially during flower ,constant 30c+ temps can stunt growth and soil tends to be slower than hydro but none the less they look great

Good looking plants! Do you have CO2 enrichment? Did wonders to my ladies when I had 30+ C in the grow room. Before that the grow was slow. From what I read, I gathered that if CO2 is implemented then higher (not extreme) temps are not an issue. The pics are about month apart. I used the diy yeast/sugar generator + added an airpump and airstone. Good luck!