I get asked a lot of questions about growing autoís, firstly I wonít say Iím an expert by any stretch of the imagination, but I have had some success with them, getting on average 2oz a plant, give or take, grown in a DR60 under a 250w HPS, so I thought Iíd put this guide together, I should stress though itís only from my experience and not a definitive guide, it just seems to work for me.
I should also mention that for my grows I use Plant Magic Supreme Soil, Plant Magic Oldtimers Bloom and Plant Magic Bio-Silicon so this guide is based on what Iíve learnt using these products and that other nutes & mediums might react differently.
Itís been well documented that autoís can have a tougher seed shell than photoperiod strains, and Iíd agree with this, Iíve read stories of people rubbing them with sandpaper and all kinds of things to try and weaken them before germinating, I personally think itís not needed, the most successful germination rate Iíve had is by following this method:
- Soak them in a glass of water for approx 36 hours
- By this time the seed might show signs of cracking
- Place seed in 0.5 litre pots with pre-wetted soil
- Put them in a propagator, if you donít have a propagator, cover the pot with a small plastic bag or cling film, and put them in a warm, dark place, I usually use my airing cupboard
- Keep the pots moist, not soaking, with a high humidity
After another 36 hours (give or take depending on soil, environment and strain), the seeds should now be breaking through the soil so itís now time to get them under light.
I always start the seedlings off under 24 hour light in a microbox using CFLís (3x 23w), after a day or so they start reaching for the light, the seed shell should also shed by itself around this time displaying its first set of cotelydon leaves, but as it was outlined earlier, they do seem to be a little bit tougher than photoperiod, so a little human interaction might be required, the method I use is to carefully, and I canít stress carefully enough, remove it with a pair of tweezers.
Feed wise at this stage should only be water, no nutes as there should be enough feed in the soil, and I usually administer it through a spray bottle carefully, I also try and keep the pots moist during the first few days under light.
At around 7-10 days, itís time to pot your girls up to their final pots, the jury is still out whether to start autos in final pots, or pot up once established, I always use the latter method which works for me, one day though Iíll have to start them off in final pots to see how they compare, but the key is to get them into their final pots sooner rather than later, certainly no longer than 14 days as unlike photoperiod, they donít need regular potting up during veg, I'll also add a small dose of Plant Magic Bio-Silicon at this stage, usually around 1ml per 2 litre over the next few feeds.
Final Pot Size
They say the bigger the better, as I grow in a DR60 (60x60x140cm) I am limited to what pot size I can use, Iíve used both round 7.5 litre and square 6.5 litre pots and to be honest, I havenít noticed a huge difference in yield between the 2, so lately Iíve stuck with 6.5 litre as it means I can fit more plants in my tent.
Once potted up, Iíll move the girls into my tent under a 250w HPS under a light cycle of 18 hours on and 6 hours off, thereís lots of talk whether they should be kept under 24 hour light, 20 hour on, 4 hours off, and from what Iíve read thereís isnít a huge difference in yield, so to take the cost of electricity into consideration, I always grow mine on 18/6 which it stays on until harvest and so far Iíve no complaints.
I did recently read that Big Buddha recommends in the last couple of weeks to start knocking the lights down gradually until you get to 12/12 to reproduce the natural cycle of the sun as you head towards the harvest date, although Iíve yet to try this method, if anyone has, it would be good to know what results you got.
At around 21 days you should start seeing pre-flowers appearing, donít be anxious to start the nutes at this stage as the key to feeding autos is less is most certainly more as they are well known for being light feeders. My last few grows Iíve completely bypassed Grow nutes and started on a low dose, usually 1-2ml per litre of Plant Magic Oldtimers Bloom at around the 28-30 day mark.
The reason I donít use Grow nutes is with potting up, the young plants generally donít need extra nutes, that said, if you start them off in final pots, you may very well need to give them a little bit of Grow before they start to flower, donít be in a rush to add them though, try and read what your plants need, if they look healthy, leave them be.
Over the course of the grow, I rarely go over 3ml per Litre Bloom, I will occasionally knock it up to 4 ml, but only if I feel they need it, and quite often Iíll do alternative feed of 3ml per litre, then just plain water and around 53/54 day mark Iíll start knocking them down so the last 2-3 feeds are just plain water.
Unlike photoperiod, autos donít need as much trimming and some growers prefer not to trim them at all, I do trim the lower 3rd of the plant a little bit, but itís mainly any dead, dying or yellow leaves as the buds develop, and Iíll also snip off some of the smaller popcorn buds which appear low down and donít really develop into much, but this can be personal preference though as there certainly no harm in leaving them.
Most breeders say autos are ready in just 60 days, now most Iíve grown can be chopped at 60 days, but to get the most out of your crop and to get a heavier stoned, itís well worth taking them longer, my target is usually 66 days, although I have chopped earlier and later, but I use this as my benchmark, itís also worth using a magnifying glass or jewellers loupe to check the trichs so you harvest at the optimum time for what you want.
So there you have it, my guide to growing autos, like I mentioned at the beginning, this is in no way a definitive guide, itís just what happens to work for me, but Iím always up for learning new methods and using different techniques, so all you auto growers out there, feel free to add to this thread, post pictures of the successes or disasters (I mean, we learn from our mistakes!) youíve had, strains youíve tried and recommend or just anything related to the love them or hate them variety of autoflowering canna.
And to finish off, hereís some photos of past autoís Iíve grown - Keep it auto
Cream Caramel Auto at 66 days
Cream Caramel Harvest
Purple hues of the Cream Caramel
Speed Devil #2
Il Diavolo harvested at 49 days
Fast Bud and Speed Devils at 61 days
Fast Bud harvested at 62 days