No announcement yet.

Best Way to Train Auto-Flowering Strains?

  • Filter
  • Time
  • Show
Clear All
new posts

    Best Way to Train Auto-Flowering Strains?

    I know we have tons of very talented auto-flower growers in this forum, and I wanted to tap into your knowledge! We are making a new page for the website about training autoflowering cannabis strains, and I was hoping you would all share your experience!

    For those who don't know: An auto-flowering marijuana plant automatically starts making buds about 3-4 weeks from germination, and most are ready to harvest by the time they're 3 months from seed. You generally only get auto-flowering seeds from a reputable breeder.

    Some Excellent Auto-Flowering Cannabis Breeders:
    • Dinafem
    • Dutch Passion
    • Mephisto <-- Over the last few years this breeder has really taken off with amazing auto-flowering genetics, highly recommended

    There are 3 main schools of thought when it comes to training autos:
    • No training - Since autos only stay in the vegetative stage for a few weeks, if you stress your plant through training, it may end up very stunted. A stunted plant produces very low yields. As a result, many growers recommend no training at all when it comes to auto-flowering marijuana strains
    • Low Stress Training (Bending) - The idea behind low stress training is to force the plant into the shape you want by bending all new stems and tying them down. The advantage of sticking only to bending is it's very low stress (hence the name) on the plant. There's almost no chance of stunting from simple bending. However, with LST you don't have the same full control over the plant's shape as you do when you actually "top" the plant (split the main cola into two)
    • Top the Plant - This is when you cut off the very top of the main stem when the plant is young, so that it grows two main stems instead of just one. Although you can top a plant without stunting it, it's possible that topping an unhealthy plant may contribute to stress. I personally haven't seen a whole lot of evidence that topping will cause stunting unless the plant was already sick.
    Just about everyone seems to agree you don't want to do aggressive training on an auto-flowering plant, for example you wouldn't want to make a manifold which takes several weeks in the vegetative stage to set up. You just don't have enough control over the vegetative stage length to take full advantage of that kind of technique with auto-flowers.

    Example of a Stunted Auto-Flowering Plant

    These auto-flowering plants were stunted when they were young by heat and overwatering. Now they've already started flowering and are just a few weeks from harvest. Even though they have a plentiful amount of light, at this point the plants are not going to get any bigger no matter what the grower does because the vegetative stage is over, and the flowering stage is already under way.

    Here's a closeup of the middle plant. You can see by the bud development that it's just a few weeks from harvest. Since it's this far in the flowering stage, you know that the plant is not going to get any bigger. The buds will fatten up, but even if they tripled in size, the grower would only get a few grams of bud. The plant just isn't big enough to support bigger yields.

    This is why many growers recommend no training for auto-flowering plants. They're trying to avoid stunting. But in the above example, the plants weren't even topped. They were stunted from heat and overwatering, not training. So I think the main point is to avoid stressing the plant when it's young, not something as black and white as just "no training allowed."

    Untrained Auto-Flowering Plant

    Here's an untrained auto - with good care and a lot of light, they can produce a whole lot of big buds without any training!

    Low Stress Training on Autos

    Here's an example of someone LSTing an auto-flowering plant by bending over the main cola when it was young

    These autos weren't topped. I only used bending and securing to try to keep them wide with many colas. I was happy, but it was a big pain trying to keep them flat. It's just a lot easier to keep plants flat when you top them, since it splits them and you can lay each side flat.

    Without topping you end up making a "spiral" with the main stem to keep it as short as the rest. Here's the "skeleton" of one plant to give you a better idea of what the training looked like underneath

    Topping an Auto-Flowering Plant?

    If a plant is really fast-growing when it's young, if you cut off the very top, the plant can usually recover without being stunted. However, many growers recommend against topping an auto because stress will stunt your plant. I personally think topping autos usually works as long as you make sure your plant is healthy and fast-growing before topping.

    To be honest, I believe other factors like overwatering or a poor environment are much more likely to stunt an auto-flowering plant than topping, especially if you're cutting off just the very tip of the plant, and not removing much plant matter.

    I've seen that many of you (check out photos from Green75 for some great examples!) who have gotten great results topping your auto-flowering plants. I've also seen many growers here get incredible results with either no training or just low stress training! So I definitely think you can succeed with any training style!

    What are your tips on training auto-flowering plants?

    So what do all the auto-flowering growers think? Do you have brag-worthy auto pictures that you'd like to see published? What's worked best for you?

    Brilliant idea Nebula! This thread = my new bible 📓
    FusionHut 5x5x6.5, Mars II LED 900W (veg/bloom modes), 4" Fusion Breath inline fan w/ carbon filter
    Coco/Perlite 70/30 "ish" in 5 gall fabric pots, GH Trio+CaliMagic+GrowTec PH Up/Down, PH test drops
    2x6" clip on fans, 1x8" desk fan, 1x12" oscillating fan


      That was a most excellent article Nebula - Thank you.
      Only one question - Which node should one top at?
      I'm in the Untrained Auto Flower Grower Team. But after watching a few videos from AutoMechanics Team - I have to try topping and LST next. I have LST'ed some photos in the past, but the autos I have grown grow so fast and their stems get so solid and thick real quick -
      ​​​​​​3 X 3 gorilla. Promix soil . Green Planet Nutes
      Mars Hydro
      Vortex in-line 6" fan


        That's a good question! I would love to hear from other auto growers too but for me I'd probably remove 4-5th node, as long as the plant is fast-growing.

        I think one of the most important things to avoid stunting is to remove as little as possible. The less you remove, the less the plant notices.
        Diagram example - how to top an auto-flowering cannabis plant
        I personally wouldn't cut off more than this when topping an auto-flowering marijuana plant.
        Never take off more than this when topping auto marijuana plants!
        You could even have pinch the stem off a little higher, above those two baby fan leaves. The arrows point to the two growth tips that would be the new "tops" if you had cut where the red line is. In this case, you would have removed even less from the plant, reducing the chance of stunting even more, and helping your plant keep as much growth as possible.

        I made this little diagram a few years ago that shows where to cut for topping, along with where to expect the new main stems. I'm not sure if it would be useful to anyone

        Topping Marijuana: How to top your marijuana plant diagram


        • alltatup
          alltatup commented
          Editing a comment
          Thanks for great tutorial!!

        My brain is exploding reading your excellent articles. Thank you!


          Looking forward to the new article, hopefully will coincide with my second grow


            I have noticed that when you top a plant if you cut it where the red scissors are in photo above then it will slow growth but if you cut it at the node below where the two new shoot are growing (I like an inch or so ) then it just shifts gears and keeps on truckin without slowing down. Thats my observation with photos dont know if autos are different will let you know soon
            new grow room built summer of 2017 ,argo max tent for veging ,big kahuna reflector, 1000hps with added leds for the full spectrum . 15th indoor grow ,5 years outside gorilla grows(stealth is the key),veg under t5s growing autos under 300w leds
            current grow




            • NebulaHaze
              NebulaHaze commented
              Editing a comment
              It's great to hear your observations! I'm not sure I understand, are you're saying this is taking off too much or too little?

            • oldjarhead100
              oldjarhead100 commented
              Editing a comment
              nebula IN your picture with the scissors , if you move it down one node where you can see the two new growth shoots and top it their the two shoots just take off but that is with photos I haven't topped my autos yet they are only 8 days those are just my observations

            • NebulaHaze
              NebulaHaze commented
              Editing a comment
              Yes, topping lower down on the plant works great with photoperiod plants (i.e. manifolding), but the idea with autos is to remove as little growth as you can, since that "wastes" as little of the plant's limited vegetative growth as possible, so you end up with a bigger plant going into the flowering stage. With a photoperiod plant you have time to grow the plant out to its full potential, while with an auto-flowering plant you're on a time limit so to get the best yields you want to avoiding wasting vegetative growth if you can. With an auto, growth=time and you don't have a lot of it.

            thank you Nebula I was looking for info on auto growing and training cant wait to see what green has to offer
            new grow room built summer of 2017 ,argo max tent for veging ,big kahuna reflector, 1000hps with added leds for the full spectrum . 15th indoor grow ,5 years outside gorilla grows(stealth is the key),veg under t5s growing autos under 300w leds
            current grow




            • St.buds
              St.buds commented
              Editing a comment
              Haha that's funny first thing I thought was green has this subject on lock I've seen his plants

            Lst for certain, I also bend branches super croppin. Defolation, and purNing under growth, not getting strong light. I also use gwe feed chart strength but I feed everyday to runoff. I keep pots on risers now to get air under pots and dry faster.
            Attached Files
            Last edited by Jibblerjoe; 12-08-2017, 09:53 PM.


            • Spanky
              Spanky commented
              Editing a comment
              May I ask what you are using for risers? I have fabric grow bags in plastic dish pans. I put $ store wire baskets, in the upside down position, under them. It works OK, but the baskets don't cover the entire bottom of the bags so they droop down a little. I do remove my runoff after each watering so they aren't really sitting in a pool of water. Maybe someone should sell grow bags with risers built in and go and Shark Tank!

            • Jibblerjoe
              Jibblerjoe commented
              Editing a comment
              sparky I got some risers through Amazon. I also use plates turned upside down. My small plants I take out of tent and place wire shelf over a tub to water them on.

            • D.A.A.S.69
              D.A.A.S.69 commented
              Editing a comment
              Yeah I got some of them risers from Amazon, I love em with them SmartPots.

            I'm in the no training camp. I just tuck a few leaves during the first couple of weeks and most of the big side branches grow up to almost equal the main in height and production.
            Completed auto grows 3

            2x4 Gorilla tent
            600W HPS
            GH Flora Series trio + Armor Si, CALiMAGic, RapidStart, Liquid KoolBloom, Floralicious Plus, FloraKleen, Diamond Nectar, FloraBlend, FloraNectar (Pineapple Rush version), Dry Koolbloom + Great White mycorrhizae & Terpinator

            Grows using this setup: 1
            Largest yield from this setup: 20oz / 567g

            Previous grows:


              Thanks for making cannabis growing so clear to all Nebula! 🐸
              I've only grown autos so far, and they all have been topped at various nodes and times. I always make sure plant is growing vigorously (!), and after the smallest amount is topped, have never really seen much slowdown. Even the 2nd node topping on Swiss Cheese (which was a little daring on my part) seemed to do no harm, and an excellent harvest resulted. Also after topping, I have been pulling down the resulting growing points so the plant gets as wide as possible, making better light coverage for developing buds.
              Glad to see your efforts to shed more light on autoflowers! They have proven themselves to be winners for me again and again! 👍🌿
              Current grows...
              Recent grows...


                Perfect timing, Nebula!! I plan on growing some autos next and have been watching others training autos on the forum. I don't think I will go to the extreme like some (yea you, Automechanics guys! 😆) but some training is in the cards! Thanks again for all your efforts to help the growing family!!
                DIY grow space 2.5' X 3.5' X 6.5'
                315 LEC
                6" Vortex exhaust fan w/speed control
                6" Carbon filter
                3- 6" fans
                temp and humidity gauge
                5 gal smart pots w/ FFOF soil
                FF trio nutrients


                  I've come to love the autoflower..she is quick and steady
                  I have found them to be very hardy plants with one purpose in grow buds...and a lot of them.
                  I noticed no difference in reaction time when I transferred my grow techniques from Photoperiod plants to Autoflower plants...none whatsoever. I have not personally grown a auto naturally..I have seen many pictures of them on here and other places.. One big fat colas in the middle surrounded by smaller but big colas as well...but that is just that...nothing wrong with it..the looks are very appealing to many people.. My problem is just that...My problem...over time I have come to love a super gnarly looking lady with big fat knuckles...that appeals to me...why you may ask...because when I'm done constructing my plants and the final finish is so jaw droppingly amazing...I stand back and literally say or think to myself...I built that...I'm the reason she is loaded with big donkey dick her...she had no choice in the matter...if up to them they would all grow like the normal Christmas tree shape we all recognize. I forced her to react the way she did...

                  What is cool to me when training autos is that you are on a time frame somewhat..but only at the beginning... You have a month or so sometimes more to shape your lady in your fashion before she decides to start making her wonderful flowers...but that's when the stopwatch quits to the stretch kicks in and provides even more bud sites... Now stay with me here....all those bud sites will mature...unclocked...quick yes...but she will not just one day be like I'm sorry all these sites are not finished yet..that is simply wrong...however long or quick it takes for those flowers to mature they will..fully..all of them..big or small..
                  so after all your training efforts you still have to worry about your light if you don't have light to all those Bud sites they just simply won't be over massively huge that's when defoliation comes into play and a lot of it sometimes every day keeping light to every single Bud site you want to smoke is very important..more light....bigger buds... Also with way less leaves the air circulation within the body of the plant improves dramatically.. lessens mold chances and stops the humidity's simple really...doing these things are key and a must in my garden... We all spend way to much time in our gardens to not want the very best yeild possible out of every single plant we care for.

                  My $.02 on the matter at hand
                  Last edited by Green75; 05-20-2017, 11:51 PM.


                  • rockman
                    rockman commented
                    Editing a comment
                    The greenman knows! 💥 Everyone can enjoy a growing style that fits them and their willingness to experiment. 😊 And love those donkey dick buds! 😁

                  • NebulaHaze
                    NebulaHaze commented
                    Editing a comment
                    I was hoping you would weigh in, Green, thanks for sharing your experience with us!

                  • Nsky
                    Nsky commented
                    Editing a comment
                    Omg so yes. Well said. Ty. Especially the "I did this myself" sitch. Yaaaassss.

                  I just love it Green75, do yo thing bro. This is my first auto and all I did was a 90 degree bend an lots of tying down, cause it was my first one I had read that you ain't supposed to mess with autos much, but after seeing your grows I think all that info is a bunch of horse hockey.Keep it up bro, changing minds.
                  Cfls for a week or two
                  315lec for everything else
                  Dug up Ms.topsoil, with perlite added
                  36x36x63 inch tent.
                  6inch - exaust - intake fans an scrubber
                  Smart pots


                  • Green75
                    Green75 commented
                    Editing a comment
                    Thanks man

                  What I noticed is that if you top an Auto, you delay when you start to flower. If I am on a tight time line I will LST an Auto but if time is not a problem then I top.


                  • NebulaHaze
                    NebulaHaze commented
                    Editing a comment
                    Yes, it seems like the real trigger to stunted autos is almost everything else besides actually topping! Over the years, it seems like the biggest problems with autos seem to be overwatering or a bad environment. Autos need to "get out the gate" strong, where a photoperiod plant can give you months in the vegetative stage while you're trying to get things right before you have to start flowering. In that way, photoperiod plants can be more forgiving if you're having trouble when you first get started, but a good setup usually makes that unnecessary!

                Check out our new growing community forum! (still in beta)

                Subscribe to Weekly Newsletter!