When breeding autoflowering Cannabis plants (also known as autos or automatic) two main techniques are used. One of them is crossing selected specimens from two autoflowering strains. This is the case in, for example, Big Devil XL Auto® (variety SWS28 from Sweet Seeds) which is the result of the cross between an autoflowering Jack Herer developed by the Sweet Seeds I+D department and a Big Devil #2 Auto® (SWS20). The other technique commonly used consists of the hybridization between an autoflowering and a photoperiod dependent genetic. In this case the resulting hybrid is not autoflowering and two more generations of breeding and selection will be necessary to fix the autoflowering trait with a rate of 100% in all the offspring. Most of the Sweet Seeds strains have been developed using this technique and a good example would be Cream Caramel Auto® (SWS22), which is the result of a cross between selected 2nd generation autoflowering genetic lines and a Cream Caramel® (SWS04) elite clone.
In the previously mentioned technique, performed in the development of Cream Caramel Auto®, the autoflowering genetic contributed with the desired trait that makes it flower regardless of the light cycle. The Cream Caramel® contributes its hugely appreciated qualities like potency, taste, aroma, quantity and quality of the resin, type of effect, etc. to the genetic pool of the new hybrid. Several generations of crossbreeding and selection will be needed to fix the desirable traits found in both parental.
Depending on the type of autoflowering and photoperiod-dependent genetics used in the cross and on the selection of the desirable traits, we can obtain new autoflowering hybrids leaning to the sativa or indica side (sweeter, spicier, etc.).
Every time we cross an autoflowering strain with a photoperiod-dependent the resulting hybrid will reduce its Cannabis Ruderalis inhereted genes by 50%. With this we manage to distance it more and more from these primitive genetics. At Sweet Seeds we decided that every time this happens, a new generation is created and this is how we establish the different generations of our autoflowering strains. It’s important to distinguish the concept used with these ‘generations’ from the so-called generations resulting from the successive sexual reproductions. Not performing this differentiation could lead to wrong interpretations.
In the last 5 years we released multiple autoflowering strains. Starting with the first autos – Speed Devil Auto® (SWS11), Fast Bud Auto® (SWS16) or Big Devil Auto® (SWS15) – that were very well received by many growers who quickly noticed and made good use of their benefits, we then passed to the 2nd, 3rd and 4th generations. Now we have eradicated almost every undesirable trait of the first Ruderalis genetics. A completely new range of strains with new tastes and aromas are born, with plants that finish their automatic flowering between 60 and 90 days after germination, with a much bigger size than their ancestors do. The flower and resin density of these strains is now similar to any photoperiod dependent polyhybrid.
At Sweet Seeds we work hard in the development of plants that are easy to grow, very aromatic and with a great taste. At the same time we want them to show an outstanding growth vigor, bigger size and greater flower production. This improvement is noticeable in our appreciated Big Devil XL Auto®, a 3rd Generation autoflowering strain recently awarded with the 1st Prize in the III Copa Cannábica Expogrow Irún 2014 that can reach to 1.5m in just 9 and a half weeks after germination. We could start calling these plants as high stature Autos. Cream Mandarine Auto® (SWS29), Green Poison Auto® (SWS14) and several other classics from our photoperiod-dependent collection also joined the big family of autoflowering strains with admirable results.
Sweet Seeds autoflowering strains are in constant evolution. Besides the initial development and improvement, every time we produce a new commercial seed we get back to the selection of the best specimens so that we can use them as parents to the next generation. Sometimes introducing a new genetic is also necessary in order to avoid consanguineous depression and keep the much appreciated hybrid vigor.
As time went by new traits appeared, got fixed through selection of our best autos and we can say that it was only in the last few years that these genetics have been subjected to a significant evolution regarding both qualitative and quantitative traits. This was the result of fixing, generation after generation, the most desirable traits from our elite clones and taking advantage of the Ruderalis genetic exclusively for the genes responsible for the automatic flowering.
After two seasons of previous work, in 2013 Sweet Seeds released a very special new range of autoflowering strains, the Red Family, with three big colorful bets ranging from red to purple flowers. The three aforementioned strains are Black Cream Auto (SWS37), Dark Devil Auto (SWS38) and Red Poison Auto (SWS39).
In 2014, Sweet Seeds kept on with the autoflowering revolution releasing a new generation of autos and opening a range of varieties of high stature and abundant production. We would like to highlight the spectacular Bloody Skunk Auto (SWS44), winner of the 2nd prize in the III Copa Cannábica Expogrow Irún 2014, with its precious reddish purple flowers, the versatile and magnificent Sweet Trainwreck Auto (SWS47) and the well famed Ice Cool® (SWS06) in autoflowering version, all of them belonging to the 4th Generation.
Let us now enter the grow zone and learn about the best way to get the full potential from these fast strains. There are no big differences regarding photoperiod dependent strains, but it’s advisable to pay attention to a few basic rules that can help us to get the most out of them.
I can personally confirm that growing autos can be addictive due to their rapid growth, something that we always seek when we germinate seeds. However, that same rapidity can turn against us if we are not watchful in some critical moments and this could lead to slower growth.
This short guide is compatible with every type of cultivation technique. It can be followed for indoor and outdoor growing, SCROG, SOG, LST, hydroponics, soil, etc. It’s also important to clarify that the highest productions will always be obtained in indoor grows.
With that being said, the only notable difference will be the different number of light hours per day that each plant receives. Outdoors it will be no more than 15 hours (between Spring and Summer), while indoors we can give them the maximum hours of light possible, which would be ideally between 18 and 20 hours of continuous light every day. With 20 hours of intense direct light and 4 hours of darkness, we can ensure a prolific development. This is why autoflowering plants can also be grown in outdoor zones with a lot of light contamination. They can be perfectly grown from germination to harvest in a balcony that is lit by street lights the whole night or even in the veg room, something unimaginable for photoperiod dependent plants as they would never reach maturity.
Let’s pay attention to some important rules that can allow us to thoroughly enjoy growing autoflowering strains:
From the main seed germination methods, the one that worked out better for me is explained as follows:
Fill half a glass of water (use soft waters), leave it to the open air for 24h, add four or five drops of hydrogen peroxide and drop the seeds into the water. Cover the glass and leave to stand for 24 to 48 hours in a warm place. Ideal temperature would be around 22ºC and 25ºC. After this, the seeds have probably already absorbed the necessary amount of water to open the shell and show a little root.
Then it’s time to transfer them to a humid paper towel or directly to a peat moss jiffy or Rockwool slab, although they could also be left in the glass of water for a while more until the root reaches to 1 or 2cm. In that case, the water should be changed every 2 days. If you use paper towels try to find natural fiber papers without any additives, inks or bleaching, as it could damage the small root. Then they should be left well covered, in a dark place with the same temperature.
Soon the roots will grow, finding their way through the paper towel, which is why it is not advisable to leave them unattended for more than 12 hours so that they don’t grow more than 1 or 2cm. Just enough to be sure that the seed has totally sprouted with good health. In my case, as I grow in soil, I pass them to jiffys and leave them there until I see the cotyledons. After this, they are moved to the first pot.
Together with germination, this is one of the most critical moments when growing autoflowering strains. These strains start flowering approximately 3 weeks after germination, which means that they have a very short growth stage and, for that reason, we should make the most of it. It all depends on these first 3 weeks of life, for which we should pay even more attention than usual. It’s not hard, but it’s convenient to be extra careful.
As I was saying before, after I get the recently sprouted seeds in a jiffy, it’s time to choose a container and the type of soil. However, it’s also time for a very important decision: start directly in the final pot or use a smaller pot and only transplant to the final one a few days before flowering starts.
At this point there is a lot of controversy as some say that it’s better to use only one container from the beginning, without any transplants. If you choose this method, you should take into consideration these two basic principles:
-The advisable size of the container (or hole in the ground) should be of at least 7 liters. Optimal would be 10 liters, while 25 liter containers would be excellent.
-Be extremely careful and try not to damage the root system of the plant nor to provoke lack of Oxygen under the soil surface due to possible overwatering in the first days, as it could slow down growth or even kill the plant.
For this reason, I personally prefer to use the other technique, performing a transplant during the vegetative phase. The transplant brings about other risks as it could totally stop growth if it’s not performed with the adequate precautions, but next I’ll tell you about the way I usually do it and if it makes sense to you, maybe you can also try it yourself.
The first container should be as small as a 1 liter container or even smaller if possible. With so little soil on it, the medium will dry faster. This will lower the risks of drowning the seedling, while allowing for a vigorous healthy root growth. We should be cautious enough to give them all the water they need but always respecting the dry cycle between watering (wet-dry-wet). Don’t give them too much water if the upper layer of the soil is still moist. When growing autos it’s also important to avoid leaving the soil completely dry for longer than 12 hours as plants have fewer time to develop new roots.
I usually transplant them to the final container when root tips are visibly coming out from the lower drainage holes, which normally happens around the 10th day of life or when the third pair of leaves appear. As previously mentioned, the final pot should have the capacity of between 7 and 25 liters.
The most advisable containers are the ones that allow the soil to ‘breathe’, like Airpot® or Smartpot®, as they permit a lot more oxygen and air circulation to the roots of these fast plants. With frequent watering, they require more time and attention, but the growth is vertiginous.
Regular containers can also be used with excellent results as long as we respect the dry cycle before watering.
Regardless of which method you choose, you should pay attention to all the factors to obtain good results.
Choosing the right soil is also important but it could be the same soil that you would use to grow any other Cannabis photoperiod dependent strain. It should be rich in nutrients, very spongy, airy and preferably a well-known brand. It should not contain an excessive amount of Nitrogen. It shouldn’t be prepared with slow-release nutrients as the plants don’t have enough time to benefit from them.
Fertilization is another important task because we can easily compromise flower production and quality of the final product if the soil gets overfed. When we choose to do the pre-flowering transplant we should know that it’s not advisable to fertilize for at least 25 days afterwards. If we use a good quality soil mix, rich in nutrients, the plant can get everything she needs from the soil during 3 to 4 weeks.
After these 25 days the flower production is in its apogee and we can add some organic flowering stimulator to help in the development of big sized buds covered by a good amount of resin. At that point the plant has already ceased growing and is now focused on filling and maturing its flowers. We can add liquid fertilizers, but always take into consideration that it’s better to use low dosages as we can then add a bit more into the next watering. It’s easier to over-fert than to under-fert a plant, so moderation is always good advice, especially with autoflowering strains.
Sooner than you think your plant will be finishing its life cycle. At this point you should use only water in the last 10 to 15 days.
Although there is no precise definition about the timing when flowering will start, there are no differences regarding any other strains when it comes to light and climate requirements. Therefore it is advisable to keep the plants under white spectrum lights (Metal-Halide bulbs are the most advisable lighting) at least for the first 10 days. After that, you can start using High Pressure Sodium bulbs.
Above all it is important to use a powerful light, ensuring an optimal flowering, while it’s also important to keep the climate controlled as with any other cannabis strain.
As you see, there are no big differences between autoflowering and photoperiod dependent plants, as at the end of the day they all need the same: love and a lot of sweetness during the whole life cycle 😉
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Thanks for Reading!
Jaypp, Sweet Seeds.
Originally published in Weed World Magazine 115