Larsvoldemor said:

So I have these plants that really is growing bad. I would still say first time grower xD
I follow VPD, keep in range ppfd & dli.(light is capable of 470W full spektrum LED)
125mm filter & oscillating fan
I try to water so it’s s little moist but not soaking wet. Always ph the water to 6.4 with 2 different testers
Fabric 30L pots with allmix(plagron) in bottom 3/4 light mix(plagron) in the top 1/4.
Strain is Zoomies from Anesia seeds feminized photoperiode. The seeds got 1cm taproot in 40hours before planting in dirt. 3-4 days to get to dirt level. So around 28 days from over dirt level.
English is not my first language.
Please help. They stop growing.
If I use nutrients it’s biobizz.

Thanks you ;-)

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Howdy

How are your light settings? If you are blasting that 470W at max and at a short distance, then light stress is something you need to consider.

About watering, you say that you keep the soil moist but not soaking. Maybe you are overwatering?! Cannabis plants can handle a bit of dryness, some say that they actually need to dry a little in between feeding them and using 30L pots with plants that small, it's very easy to overwater. Maybe you need to let them dry out a bit?!

Are you following the BioBizz feeding schedule? I use BioBizz myself and I usually start feeding them after about three weeks, just tap water first three weeks, and then I begin feeding at 50% strength. I then increase nutrients to 100% over time.

Can't say if you problem is lightstress, overwatering or a nutrient issue or all of them, but those are my thoughts on it. Hope you figure it out.

Probably the two most common stresses are light and wind, that fan looks like it's stripping the leaves of water more than the light is.

If you follow vpd don't put thermometers in the light, they need shading from all light radiation as were only wanting to read the air convection and light will heat a meter above that air temperature.

I generally use just my inline to pull enough air through a tent, it pulls enough that the small wattage of light in there can't heat it by much and light doesn't heat air directly it has to hit a surface and warm that to indirect heat air, how the sun warms the earth.

Getting better temperature readings may help you achieve better growth conditions. People who heat their meter with the light always struggle to cool that and end up blasting too much wind.

Hope that helps, the physics of measuring heat can be a little complex at first but you will find a better environment and vpd that way

i agree with the above comments,..
light too close
temp a bit high
fan pointing at plants
incorrect watering habits
shouldn’t be ph’ing
over mothering,..

KG1 said:

Probably the two most common stresses are light and wind, that fan looks like it's stripping the leaves of water more than the light is.

If you follow vpd don't put thermometers in the light, they need shading from all light radiation as were only wanting to read the air convection and light will heat a meter above that air temperature.

I generally use just my inline to pull enough air through a tent, it pulls enough that the small wattage of light in there can't heat it by much and light doesn't heat air directly it has to hit a surface and warm that to indirect heat air, how the sun warms the earth.

Getting better temperature readings may help you achieve better growth conditions. People who heat their meter with the light always struggle to cool that and end up blasting too much wind.

Hope that helps, the physics of measuring heat can be a little complex at first but you will find a better environment and vpd that way

Click to expand...

I have 3 different hygrometers 3 different places in tent for optimal readings then I take the avg of that and do the VPD
Maybe I will try put the fan in other direction is what is reading ?

GNick55 said:

i agree with the above comments,..
light too close
temp a bit high
fan pointing at plants
incorrect watering habits
shouldn’t be ph’ing
over mothering,..

Click to expand...

Can the light really be too close even if it’s turned down to the right amount of dli? the light is 300W at 75cm = 24 dli

Randyy said:

Howdy

How are your light settings? If you are blasting that 470W at max and at a short distance, then light stress is something you need to consider.

About watering, you say that you keep the soil moist but not soaking. Maybe you are overwatering?! Cannabis plants can handle a bit of dryness, some say that they actually need to dry a little in between feeding them and using 30L pots with plants that small, it's very easy to overwater. Maybe you need to let them dry out a bit?!

Are you following the BioBizz feeding schedule? I use BioBizz myself and I usually start feeding them after about three weeks, just tap water first three weeks, and then I begin feeding at 50% strength. I then increase nutrients to 100% over time.

Can't say if you problem is lightstress, overwatering or a nutrient issue or all of them, but those are my thoughts on it. Hope you figure it out.

Click to expand...

Light is at 300W 75cm giving 24 dli
I thought for sure I had to keep them moist when they are this small ?
I will take the next few days to make sure it dries a little bit. Is the rule still like 1 fingers deep it has to bee dry?
I gave them 50% strength 3 days ago with Bio grow & bio heaven. Because i was thinking the start to lack N because of limegreen color

Larsvoldemor said:

Light is at 300W 75cm giving 24 dli
I thought for sure I had to keep them moist when they are this small ?
I will take the next few days to make sure it dries a little bit. Is the rule still like 1 fingers deep it has to bee dry?
I gave them 50% strength 3 days ago with Bio grow & bio heaven. Because i was thinking the start to lack N because of limegreen color

Click to expand...

I don't measure dli myself, but I do think 300W sounds like a lot even at 75cm. For comparison, I grow with only 100W from seed to beginning of flower. Here is an example of what you can achieve with that in about two months from seed. Unless you are absolutely certain that what you are doing with the light, I would suggest that you dial it down, at least until you have everything under control.
When the seeds are germinating it is essential that they keep being moist. Seeds that has been activated will die if they are being allowed to dry. So small plants are more sensitive to dryness, but I would say that that is only something to worry about for the first week or so. It seems way more common that growers overwater than it is that they underwater. It can be very helpful to overwater and underwater just so you get to experience what that looks like. It might help you in the long run.

I used to do the 1inch or 1 finger deep method when it comes to figuring out when I needed to water, but I find that the bigger the pot the less effective that method is. A large pot can hold much more water under the surface than a small pot, so even if the top soil is dry in a large pot, lots of water can still be present in the lover part of the pot. What you need to do is you either lift the pot to get a feel for how much water is in the pot according to weight, you should do this daily, or you can actually use a weight to whey the whole pot and plant. It takes a bit of practice, but over time you will get it.

Sounds about right what you got going with the nutrients. Limegreen color can indeed be a sign of n deficiency.

What I would suggest you do is that you set the light to about 100W and at a distance of about 60-70cm and then you let the pots dry a bit. This can take a while depending on how much water is in the pots. It may be as much as a week or more! Then observe if the plants are improving and have patience.

I just went through a search here on the farm. Went to diaries and searched plagron allmix. Dozen good write ups and a few poor ones.
Watering looks to be an issue with this mix. Does not list any buffering agents which means when the soil stays wet the pH spikes. I do not and never have used plagron but you can run the same search. Lots of info linked in various diaries.
This is a soil less medium but should still be treated as soil for purposes of a dry/wet cycle.
You do have tip burn so I til this is handled turn down the lights a bit.

JIMKSI64 said:

I just went through a search here on the farm. Went to diaries and searched plagron allmix. Dozen good write ups and a few poor ones.
Watering looks to be an issue with this mix. Does not list any buffering agents which means when the soil stays wet the pH spikes. I do not and never have used plagron but you can run the same search. Lots of info linked in various diaries.
This is a soil less medium but should still be treated as soil for purposes of a dry/wet cycle.
You do have tip burn so I til this is handled turn down the lights a bit.

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Remember it well buffered and reasonably fertilized, Plagron wouldn't miss a simple thing like this in its all mix. Great company all round

Larsvoldemor said:

I have 3 different hygrometers 3 different places in tent for optimal readings then I take the avg of that and do the VPD
Maybe I will try put the fan in other direction is what is reading ?

Click to expand...

Your reading give you false values.

There's a certain amount of science in radiation conduction and convection you need to understand first.

The met office shade from all direct wind and light for a reason and because of the science. You don't want to read light or wind, think about it they heat and cool objects but this isn't air temperature. Same principle if you put a meter in sun on sunny 25c day it will read over 25c because the sun warms it.

Plants don't want wind past a very small level, 0.5-1.0m/s is a generally accepted speed. Your fan pushes wind at much higher speeds it simply strips water from the leaves. Extraction can achieve this better than osc. Fan in small tent.

I think you're over-lit and over-watered. The plants are the best light meter any of us have. Happy leaves are flat, level, and green. If we see contortions of any kind (taco-ing, edge curl, twisting, etc), or colors other than green, the plants want less light. The texture of the leaves suggests to me that they're being watered too frequently. When we can see individual venules on the leaves, that's almost always too-frequent watering. I don't have hands-on experience with your media, but if it's amended with organic stuff like worm castings, they need a longer dryback.

Thank you all for the nice reply’s I will look into turning the light down.

Larsvoldemor said:

Light is at 300W 75cm giving 24 dli
I thought for sure I had to keep them moist when they are this small ?
I will take the next few days to make sure it dries a little bit. Is the rule still like 1 fingers deep it has to bee dry?
I gave them 50% strength 3 days ago with Bio grow & bio heaven. Because i was thinking the start to lack N because of limegreen color

Click to expand...

Just wanted to point out that testing for dryness with your finger only works if your plants are in the correct size pot for their current root size. Your plants look a bit small for those pots, so that may be why you have been slightly over-watering them as pointed out above. In pots that size with plants of that size you would not want to fully saturate your medium. It will stay wet for too long which can lead to more problems than just over-watering, such as root rot or pests (less chance for pests indoor though).

THCosmic said:

Just wanted to point out that testing for dryness with your finger only works if your plants are in the correct size pot for their current root size. Your plants look a bit small for those pots, so that may be why you have been slightly over-watering them as pointed out above. In pots that size with plants of that size you would not want to fully saturate your medium. It will stay wet for too long which can lead to more problems than just over-watering, such as root rot or pests (less chance for pests indoor though).

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I was going to say the way this industry is going these pots are not nearly big enough for those small plants lolol

THCosmic said:

Just wanted to point out that testing for dryness with your finger only works if your plants are in the correct size pot for their current root size. Your plants look a bit small for those pots, so that may be why you have been slightly over-watering them as pointed out above. In pots that size with plants of that size you would not want to fully saturate your medium. It will stay wet for too long which can lead to more problems than just over-watering, such as root rot or pests (less chance for pests indoor though).

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All my info I got from a friend who is doing a pretty good job I’m just sad I can’t figure out what’s wrong. For now I will start to do less. And change the light intensity pray for me

When is the best time to do a transplant. Does it have to do with height of the plant og age of the plant

Larsvoldemor said:

All my info I got from a friend who is doing a pretty good job I’m just sad I can’t figure out what’s wrong. For now I will start to do less. And change the light intensity pray for me

When is the best time to do a transplant. Does it have to do with height of the plant og age of the plant

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I transplant when I can't go at least 4 days between waterings.