You may have heard that autoflowers produce small yields, but genetics have come a long way in the last five years, now some autoflowers can even rival photoperiods. And when you take into consideration that they can be grown from seed to harvest in as little 8 – 10 weeks you can see why they have become so popular.
Boosting autoflower yields isn’t difficult if you plan your grow in advance. Here’s some key tips for you that will have you producing high yielding autoflowers in no time!
The keys to growing high yielding autoflowers
Genetics – start with high yielding autoflower seeds
It may seem obvious but if you want to produce big autoflower yields then you need to choose the right genetics to start with. Growing one of the top 10 highest yielding autoflower strains will give you the best chance of achieving those monster yields.
You also want to start with fresh seeds that have been stored in a cool, dry place.
The most exciting thing about growing autoflowering strains is the enormous harvest you can get in such a short amount of time. This, however, does come with a caveat; autos don’t give you much time to get plants to harvest. If you’re going to grow autos, you need to plan and set up your grow room beforehand.
Think you’ve got all the steps, right? Not so fast. Each autoflowering strain has specific needs, so it’s essential to cut no corners and give your plants the best possible start in life. Before you go about buying plants and equipment, first determine what you will need for each stage in the life cycle of your plants.
While it is important to provide plenty of light, you should also keep in mind other key factors that will increase your harvest. These include the right medium (one that holds moisture well), container, and good airflow. If using a grow tent or other grow space, give it some planning before setting up.
Grow autoflowers in one pot from seeds to harvest
Autoflowering cannabis strains are the fastest growing type of weed strain and it’s impossible to tell when a plant can take it, which is why growing autoflowers in their final containers is always best.
However, if you already started growing in a small pot and transplanting is required, a solution to increase autoflower yields is minimizing stress or shock by transplanting as late as possible. The longer the plants remain in their original containers, the more developed they will become.
The most common mistake when transplanting autoflowers is doing it too early. It’s tempting, as their roots develop quickly, but it’s not the best idea. Autos are hardy plants, and transplanting does not hurt them; however, if you can wait a little longer before transplanting, your plants will benefit from the extra time to build their root system even more.
There’s no rush to transplant and never force a seedling into an unsuitable growing medium. If you are in a hurry, ensure the new container’s mix is the same as that in the original. Before transplanting, the roots must be strong and thick. Use your hands to check the sturdiness of them. To be sure that plants don’t become stressed after transplanting, water the soil deeply from time to time, but don’t overdo it.
Grow in the right environment and right size pot
Every autoflowering strain is different because they stem from different original plants. They can either have the Indica or Sativa background or have different frame sizes and shapes. However, the type of container you choose plays a major role as well. Some people use containers that are too small. Autoflowers require at least 7-gallon containers, but bigger sizes are preferred for bigger plant sizes to get great yields. Autoflowers love aerated soil that drains very well and pots with drainage holes to prevent root rot.
Optimize your nutrients
One of the common mistakes beginning and intermediate growers make is giving their autoflowers more nutrients than they need. Autoflowers are not like photoperiod plants. They have very small, compact root systems and require a different approach to feeding.
Not only does overfeeding harm your plants, but it’s also a waste of your money. Most autoflowers require minimal nutrients to grow healthily. Check your run-off pH, using a pH monitor to calibrate your feeding and prevent nutrient burn or lock out.
However, there are some autoflowers that are heavy feeders, such as gorilla glue or tangie automatic. For these strains, you need to feed them more heavily. If your nutrient schedule calls for 5ml per liter and you are afraid to overfeed, start with 2.5ml or even 1.25ml and then advance up the dosing ratio as needed.
While it’s not a good idea to use nutrients during the beginning stages of growth, you should start as soon as flowering starts. A mild nutrient solution is fine for this stage.
Monitor the PH levels
It’s important to keep track of your pH levels. Plants rely heavily on the correct pH for essential nutrient uptake. If your levels fall below 5.5, then the plant will struggle to absorb calcium and magnesium, vital for growth and flower production. Low levels of calcium and magnesium, which is quite common in growing autoflower growing, will result in weak stems that can snap under their own weight or from external forces such as strong winds.
Autoflowering cannabis strains tend to prefer slightly acidic soils or nutrient supplies, with a moderately higher PH value—such as 6.0-7.0 for most strains.
If you’re growing in soil, make sure the pH ranges within 5.7 to 6.3.
If you’re using a hydroponic system, make sure your water supply is well-buffered and stays within a pH range of 5.5 to 6.5.
More light leads to bigger autoflower yield
Cannabis grows in all kinds of environments—small spaces, greenhouses, cold areas, or hydroponic. But, it thrives when it gets more hours of light during the vegetative stage.
If grown indoors, grow your plants on at least 18 hours of light, followed by 6 hours of darkness, this light cycle is recommended to get huge autoflower yield. Just start providing 18 hours of light after your seedlings emerge. Plants grow robustly and flower no matter how many leaves they have, as long as they can receive enough light.
With autos, you have more leeway when it comes to cannabis grow lights, as they still produce good yields even if you use CFLs or fluorescent tubes. However, they like HPS or LED lights the best. A full-spectrum LED light works the best for an autoflower. If you use the LEDs, go as high as lumens as possible.
Growing autoflowers outdoors is a great way to achieve the highest yields with minimal effort. When grown outdoors, autos prefer to grow in areas that receive at least 12 hours of sunlight. If you can give them 16 hours, they’ll grow even bigger buds.
Plant training techniques
Low-Stress Technique (LST)
A lot of growers want to achieve buds full of resinous THC-rich glandular trichomes. To achieve this, it’s recommended that LST (Low Stress Training) is a more suitable approach for autoflowering strains, as autoflowers don’t fare very well with the amount of stress that most photoperiod plants endure during their vegetative period.
Using LST training you will really begin to maximise your autoflower yields. With the LST technique, growers bend the plant’s stems so that the it grows into a much wider shape allowing the plant to absorb much more light. Cannabis plants often grow one main massive cola at the top while the rest of the plant produces small budlets (also known as popcorn buds, or popcorn nuggets). LST can help optimize and direct light penetration, air circulation and energy distribution to each cola so that they all get bigger.
Cannabis plants like the feminized auto AK47 take regular training very well. With LST, you straighten/train your cannabis plant in a shorter time than you would have if you used HST techniques. This is important for autoflowering plants because they don’t need the vegetative period as long as photoperiod plants do. LST makes the growing process easier, along with helping to prevent some yields limiting ailments such as heat stress.
Topping and Fimming
Topping and fimming are also some commonly used cannabis plant training techniques to increase autoflower yield. By removing parts of the main stem, you’re forcing side branch(es) to grow at the top because their tip has been removed, also known as topping. Fimming is another topping technique that removes the top node where the leaf and stem meet instead of cutting off the entire top part.
Growers must keep in mind that training techniques should only be used on healthy plants. It is also helpful to know the phase of plant growth when training. Training can best be executed during vegetative or early flowering stage to increase yields, reduce plant stress, and save time.
Whether upright or short, all plants benefit from training by being tied or clipped to support. The goal is to get the plant’s stems and branches to grow horizontally because that’s where the flowers form. You can start seeing how your plants will look as they mature.
Recommended high yielding autoflower strains
There is a more comprehensive list of highest yield autoflower strains which we totally recommend you checking out. For those who may have problems with having too many choices to decide, below is a pick of 3 high yielding auto strains to try.
Gorilla Glue Autoflower
22 – 25%
500 – 600 g/sm
6 – 8 weeks
60 – 100 cm
An ideal strain for any cash croppers Gorilla Glue Autoflower is capable of producing 400g/m2 of some of the most potent bud around. With THC levels up to 25% this strain doesn’t compromise on potency at all when you produce these big yields.
Big Bud Auto
15 – 18%
400 – 500 g/sm
6 – 8 weeks
60 – 100 cm
Big Bud is one of the most productive strains in cannabis cultivation. This autoflowering plant, of Indo-Thai, Mexican, and Afghani influence, was bred using Jack Herer’s original clone to get the best possible characteristics from this strain. A true factory of buds that in 70-80 days will produce between 400-500 g/m2 without needing extras like pruning or elongation. To do this with a total lack of maintenance, you need a LEC 315w lighting system that will place your plants 20 hours a day.
Best autoflower seeds for huge harvests, Big Bud Auto delivers 25% larger plants with bigger yields than original Big Bud. It’s a fast-flowering autoflowering cannabis strain that grows like an Indica but delivers the taste, aroma, and potency of Sativa. This highly potent 85% Indica/15% Sativa is absolutely loaded with THC and offers a strong psychedelic experience for novice and experienced smokers alike.
Incredible Bulk Auto
19% – 22%
over 600 gsm
10 – 12 weeks
100 – 180 cm
Incredible Bulk Auto by Dr Krippling is a cross of Big Bud, Super Skunk and Green Spirit, three of the biggest cannabis breeds known to man. The result is a one of the highest yielding autoflowers ever created. Dr Krippling claimed that Incredible Bulk Auto can yield up to 650g/m2 and with THC levels of up to 22% this strain will keep you supplied with some top quality dank for quite some time!