Sour diesel autos not getting tall

I have 2 ilgm sour diesel autos. They are short and seem to not be getting tall. They are 26 days old. Both plants have leaves touching dirt. Is there something I’m doing wrong. I’m growing in a 2x4x5 tent I have 2 Vivosun 100 watt full spectrum lights. Lights are 2 ft above plants… I have a humidifier in tent and keep it at 50%. Temps with lights on are 80 degrees and lights off are 68-70 degrees. I have a runtz in tent at 28 days old and growing fine and already starting to flower. Any advice greatly appreciated

Also will be feeding this afternoon when lights come back on.


You can encourage them to stretch out by decreasing light intensity.


In my opinion, to warm to low of humidity.
VPD of 1.75 is not ideal causing too much nutrient uptake and getting those nitrogen toxicity clawed growth.


They look good. Maybe too high temps and low humidity, but not too far off. My first two sour diesel auto grows also stayed short due to a close and bright light. I raised and decreased my light intensity during the first 3 weeks for my current grow, and it allowed them to grow taller before auto turning to flower. Taller plants make it easier to do low stress training (LST), with longer branches and space between the colas.


This is just my second grow. What temps and humidity do you recommend. I did runtz on first grow and did pretty good with them. Been keeping same temp and humidity as my first grow. Also do you think I should just give water with no nutrients on next feed.


With ruderalis genetics I generally go on the lower side. Around 74, 55/60% until mid flower.
Picture before is about the time I start to drop humidity.


Here are my sour diesel autos today at day 32. Less light intensity means taller plants that are easier to train. After a year of reading it on here, it still took me three times to figure it out on my own, lol.


They look nice but flowering by day 32 would drive me nuts. This is usually around the time I am topping my photos for possibly even setting a manifold.


Do you think if I turn down light intensity and raise lights that will help. I have a dimmer switch on light that goes 25,50,75,100%.

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I would set the lights so they give your plants the most PPFD they can put out.

My first grow was zkittles autos and I gave them too much light. Even after stretching they weren’t much over a foot tall. After that grow I read up on DLI and got the Photone app. You should give that a try. When you use DLI you can easily and accurately make sure your plants are getting the right amount of light every day.

@Nicky has a thread on here called “start using DLI”. The thread has gotten long, but there’s a lot of useful info and graphs in it. Also, I just looked up sour d autos on ILGM and it says they’re compact plants. Zkittles are also listed as compact.


Some good advice here but I’ll try and help summerize it but first it is important to remember that auotd are very picky, so it’s important to get conditions as near to perfect as possible to ensure good growth.

Lower light intensity will encourage stretch, you ideally want about a 1/2" between nodes, so if they are to tight give less light.
More light can only be used if all other factors are ideal.

Your VPD is off, google image a cannabis VPD chart and hang it in your grow space, ideal temperature is 78*F for lights on don’t go past 79, at 80 your in the red.
During veg humidity needs to be much higher than 70%, add a humidifier if you must.

Airflow, hopefully you have a programable duct fan like a AC infinity T series. Use a programable duct fan to only turn on if temp hits 79F OR X Humidity ( veg you want 75-80% humidity), once flower kicks in and plants are bigger these variables will change and the fan can be on constant to filter smell more efficiently.

Hopefully your exhausting air OUTSIDE! if your not doing this the plants are Co2 starved, aka they can’t breath because the room air is to rich in oxygen.

Lastly I would ask what medium your growing in, and how your feeding/watering, what’s your process?
If it’s hand watering then please ensure your doing it by weight.
If your in soil what type of soil did you use? How did you layer?
If your in coco and perlite or peat and perlite then my question would be what are you feeding, when, how etc.

For both ide like to know how much run off your getting and what the TDS/ PH is of the water/nutrient you feeding.


@Outlaw what this guy right here said!!! It’s seriously important!


So about how many " away did u have your light this is my 1st grow an im also doing a sour diesel an mine is growing exactly the same