autoflower tips

Tips for growing autoflowering cannabis plants

These days, autoflowering cannabis seeds are highly sought-after because they’re easy to grow and allow the grower to obtain several harvests in less than 2-3 months.

This type of strains can be grown in small terraces or balconies, as they tend to produce small plants of no more than 1m in height, provided they are grown in pots. When cultivated on soil, autos can easily grow higher than 100cm, and produce more bountiful harvests than in pots.

Think Different photo by Jon Peta from C.C.

But to get the best results from auto plants, you need to take into account several factors, in order to achieve a smooth running from the very beginning and to avoid any problems during the process.

Let’s see how automatic cannabis should be grown to obtain optimal and generous harvests.

Main traits of autoflowering cannabis plants

First of all, you should bear in mind that these plants don’t respond to the standard photoperiod, which means they don’t rely on the amount of sunlight they received during the day to start flowering.

Therefore, their vegetative period is limited to a few days, and the number of days can vary depending on the strain, but it’s usually between 15 and 30. This is the timeframe needed by automatic plants to feel mature enough to start flowering. Cannabis needs a certain amount of time to grow and start producing flowers, as well as trichomes, in order to catch the male’s pollen and be able to reproduce the species.

Think Different seedlings

It’s during this limited period of time that you have to be extremely careful, so the plant is safe and doesn’t stop growing. Over-fertilization, overwatering, high humidity, lack of light or direct sunlight, the wrong substrate, strong winds, and lack of nutrients, are a few examples of factors that can reduce the size of your plants.

Why are autoflowering plants so small?

As we have seen, there are several reasons for these strains to remain small.

Seed germination and first repotting

This is an important step that many growers overlook, but it’s vital if you want to prevent any future problems.

You can germinate your seeds the usual way, with the paper towel method, jiffy pellets, etc. We prefer to do it between two wet paper towels and then use the jiffy pellets, as this allows for the first and only repotting that automatic plants need.

How to germinate cannabis seeds

Once the seed germinates, the primary root penetrates the jiffy and emerges on the other end, and the stem stretches a little bit, you can repot the seedling into its final container. Avoid re-potting your autos more than once, unless you are going to keep the plant just for a few days in the first container.

Pot size for autoflowering plants

The size of the pot is very important, as the smaller the pot, the smaller the plant. The reason is easy to understand: the plant does not have enough room to expand its roots, which results in slow growth.

When using a small pot, the plant’s root system will quickly fill out the container, and then will slow down its growth, since there won’t be more substrate to fill. Given the impossibility to continue expanding further at the same pace, the aerial part of the plant will be flatter and smaller. In order to obtain the maximum production from automatic plants, it’s recommended to grow them directly in the soil for several reasons.

Think Different growing in soil

When the root reaches the bottom of the pot and can’t find any more substrate, the plant stops growing. This is why it’s important to use pots that are tall rather than wide, so the plant continues to develop during the 30 days of its vegetative period.

How to prevent automatic plants from growing small due to a lack of substrate

The best thing is using containers that are large enough for the auto strain to develop without halts or stagnation during the 15 to 30 days of their vegetative period.

These pots should be much taller than wide, so the roots can penetrate more deeply into the substrate and the plant can become bigger and more branchy. These containers are called 18L Automatic plant pots, or square pots, but we also recommend smart pots and Alchipots, which burn the tips of the roots creating more hairs for enhanced nutrient uptake. You should use pots of no less than 20L.

The growth rate increases as plants grow

If you use smaller containers, even if they’re made of fabric, you’ll also get smaller plants. The main advantage of a fabric pot is that it allows for higher water evaporation, providing the substrate with longer wet and dry periods, which stimulate the roots and make them grow further.

Watering autoflowering plants

Another important factor you should take into account to ensure that everything runs smoothly and to avoid growth stagnation during the vegetative period.

Since you’re only going to repot your seedling once, and the first container will also be the final one, the plant will always be at odds with the size of the pot.

When growing non-autoflowering strains, we use small containers in order to have better control of the irrigation, because, in the event of overwatering, the pot will dry quickly.

Think Different growing steadily

But, what happens to small plants in large containers? You can’t water big pots with large amounts of water on the first day and wait for them to dry. If you overwater them, the substrate will be wet for many days, stopping the plant from growing, since it won’t need to go in search of water during those 15 days.

How to water autoflowering plants

How should you water your automatic strains? With very little water, since the pots will be very large and the plants very small. 200-300ml per plant is enough for 18L pots, which means you can water them every 2 or 3 days without flooding them. On sunny days with high temperatures and low humidity, your plants might need more water, so you can double the amount, but try not to saturate the container.

Continue with this irrigation regime until your plant has grown a few inches, and then provide it with a higher amount of nutrient solution.

Think Different halfway its growing period

Once your auto has grown and you can tell it’s about to flower, treat it like a regular plant. At this point in time, the root system will have spread almost in its entirety, and it will be able to absorb a bigger amount of water in less time than when it was smaller.

Autoflowering plants nutrition

How should you feed your automatic strains? This is also a recurring question between many new growers.

Feeding autoflowering plants can be tricky at first, especially if you still haven’t mastered cannabis cultivation. You need to be careful not to overfeed your plant, as this can be counterproductive with this type of crop.

Think Different with the right amount of nutrients

An excess of nutrients will cause the leaves to adopt a claw-like form, and the plant will stop growing due to salt accumulation. While it’s true that many times the growth doesn’t slow down too much, an excess of nitrogen can affect the flowering period.

We’re back at the limited growth problem. After a month or so of growing, the plant will start flowering, and if you overfeed it at this moment, it won’t have time to use the stored nutrients (nitrogen in this case), and will end up flowering with a nutrient imbalance in its metabolism.

Think Different with the same treatment but a lighter green colour

This imbalance means that a plant with an excess of nitrogen will stretch further, increasing its internodal spacing and producing slender buds. The excess of N makes the flowers small and compact, which at a visual level can be seen as 4 buds scattered around the plant, instead of a single and large bud at the very tip of the plant.

Can you flush your cannabis plants to leach off the substrate? Yes, you can, but many times it’ll be too late since the buds will have developed differently on a morphological level.

How to avoid nitrogen overfeeding

To avoid problems arising from excessive use of fertilizers, the best solution is to use a potting soil that only needs water and some or other root stimulator throughout the vegetative phase.

Think Different finishing stretching before flowering

This type of soil, such as All Mix, is designed so the plants can keep growing during 4 weeks without anything else. After this period, you should use liquid fertilisers.

As we discussed before, your plant has 4 weeks to grow, so this soil is ideal to avoid any problems from the beginning, and once the plant starts blooming, you’ll need to provide it with bloom fertilisers, as if it was a standard, photoperiod plant.

The best soil for automatic plants

Although many people overlook it, the substrate is the basis of the entire crop, which means that if you don’t have the best substrate, everything becomes much more complicated.

A good-sized Think Different

The ideal substrate for autos must be very fluffy, as their roots and growth are time-limited, and you should allow for a maximum expansion before they initiate the flowering period.

If instead of using an adequate substrate you use any other, your plant will have difficulties to conquer it, creating a very small root mass, which translates into a slow and stagnant growth with minimal nutrient uptake.

Using trichoderma is a great option to boost the plant’s root system in order to make it stronger and more resilient and effective. It will also protect the roots from possible fungal infections, such as pythium, and will help the plant to have a better symbiosis between the substrate and the root, allowing for a greater ion-exchange which will highly increase the nutrient uptake, especially when using organic fertilisers.

Think Different at the end of its flowering period

A mix of white and black peat, perlite and coco is a good combination to create a quality substrate. We recommend mixing coco coir with soil to make it fluffier, and also to get lower water retention to facilitate the drainage and the drying of the substrate.

If the entire process runs smoothly and without any issues, you’ll obtain high-quality buds, since modern automatic strains have improved a lot in terms of production, potency and flavour.

Think Different ready to harvest

We hope this guide will help you to achieve an easier, more balanced, and problem-free crop, so you can enjoy marijuana of the highest quality.

Growing automatic strains is very popular among many growers taking their first steps in the cannabis world. Learn about the needs of autoflowering pl

10 tips for autoflowering cultivation

Growing autoflowering cannabis varieties

Autoflowering varieties are the solution for many growers. These fast and discreet plants have earned a place in the garden of many houses, but we have found that some users grow them in the same way as normal ones.

In this article we are going to review the 10 most important tips to get a great yield with automatic flowering cannabis plants. Do you want to know which ones they are? Well, here they are….✍

1. Choose modern automatic genetics.

In general automatic genetics have evolved a lot since the first Lowryder. Thanks to selection and breeding of the populations with the best individuals, these plants increasingly resemble the normal photodependent ones, so the current ones are better than those of 10 years ago.

Years ago it was difficult to achieve a large production of tasty and potent buds with autoflowering seeds. Luckily this changed and nowadays it is relatively easy to get a good autoflowering crop with a lot of resin, THC above 20%, and great aroma and flavour, as with the Haze XXL Autoflowering.

2. Use a new, aerated and nutrient-rich substrate.

Autoflowering plants have a very fast vegetative growth cycle of just 3 weeks. Once this time has elapsed, they begin to flower spontaneously, regardless of their size or growing conditions.

The final production of an automatic flowering variety is directly related to the total size of the plant. This is why it is so important that during the first 3 weeks of life nothing slows down their development.

The key to achieving maximum growth and development during this time is to create a good root system, and to achieve this goal it is best to prepare a foamy, loose, aerated substrate to oxygenate well, and rich in nutrients.

image of a special soil for the cultivation of autoflowering seeds, fine-textured and foamy*

3. Final pot of at least 2,64 US gallons.

At this point there is some controversy, as there are growers who prefer to plant autoflowering seeds directly in the final pot, and others who choose to do transplants. We can tell you that you can achieve great performance in both ways, as long as you do things right.

Is it better to transplant autoflowering plants?

From our point of view it is, the nutrients of the substrate are better used making transplants. But be careful with this, if the roots are damaged during the transplant or the plant is stressed, the development in general can be stopped, and so that production is reduced.

When a photodependent variety is transplanted we can wait for the root system to fill the entire pot. This ensures that there is hardly any chance of damaging the roots, since you get all the roots bread compact. But with autoflowering plants we cannot wait with a small pot for the roots to fill it, because then we would be losing development and time. When the root system has not filled the entire substrate you have to be very careful with the transplant, some deep roots with few branches can break during the process. If you choose to transplant I recommend that you germinate in a pot of 0,8 US gallons, and after 20 days make the transplant to the definitive pot.

If we prefer not to risk in the transplant and to plant directly in the final flowerpot it is necessary to consider 2 important details. The first is not to overwater during the first few weeks. We have seen seedlings, or small plants of 2 or 3 pairs of leaves, in pots of 5,28 US gallons soaked, and this is not good at all. When you are not going to transplant, remember that you can water every day a little, but keep in mind that when the plant is small it has hardly any roots to absorb, so you only have to water around the stem, and gradually water a little more surface. Once we water the whole pot it is important to respect the dry cycle, as it is the only time that the substrate is oxygenated, and not water again until it has dried a little, which is the second detail we see frequently.

If you already have your plant in a small pot and need a solution, here’s the trick:

  1. Cut off the bottom of a “cup” or a 7-10cm pot.
  2. Place 5cm of coconut: wet perlite in the bottom of a 10 litre pot.
  3. Fill the wide part of the 10 litre pot with coconut perlite (dry)
  4. Bury the 7-10cm cup or pot halfway down in the 10 litre pot. Fill this with coconut-pearlite as well.
  5. Now plant your sprouted seedlings in the cup and water in the usual way.
  6. When watering your autoflowering plant, be sure to water ONLY in the small pot for the first 10 – 14 days. This will ensure that the seedling receives the water it needs (and depending on its age, the nutrients as well).
  7. Meanwhile the main root of the car will grow downwards, an accelerated growth outside the wet coconut-pearlite layer, just know that it is in the bottom of the 10 litre pot.
  8. The main root sends an extensive network of smaller root hairs that also seek that water source.

Scheme of an autoflowering transplant

4. Use Trichoderma and Mycorrhizae.

It is not essential, but it is so interesting that we always recommend adding microlife to both the substrate and the irrigation. These beneficial fungi and bacteria have several functions that help improve the performance of autoflowering plants.

The first advantage of using Trichoderma and Mycorrhizae is that they act as a root system protector against fungi and other external pathogens. These microscopic beings produce a mycelium that colonizes the entire substrate to prevent malignant mushrooms from being able to access.

The other great advantage is that through this mycelium it can help bring food to where the roots do not reach. Plants eat more and that affects their overall health.

Its composition is basically Harzanium Trichodermas characterized by plants and stimulate benefit and therefore our crop yield….

5. Add root stimulator to the irrigation during the first 3 weeks

During the first 3 weeks of life, that is right, during the fast vegetative growth phase of automatic genetics. This point has to do with the previous 3, that is to say, with the objective of reaching the maximum development both radicular and aerial.

Ideally, an organic root stimulator should be used, so that it is compatible with microlife and can work in combination. Once the plant begins to draw pre-flowers it is time to stop adding the root stimulator, and start watering with flowering stimulator.

6. Do not prune the main tip.

It is not really very interesting to do apical pruning or F.I.M., since they do not take advantage of it to optimize production. In this case the opposite can happen, because of pruning development time is lost and instead of improving the crop can be reduced.

In indoor cultivation it is interesting to prune from low to autoflowering plants, especially the so-called Auto XXL. These plants grow quite a lot, and in many cases the light from the focus does not reach the lower parts well, interfering with their normal development. If you need help when making any kind of pruning in cannabis, I recommend you read this article that talks about it.

7. Continuous watering but with little water.

There is no unanimity on this point either, but we recommend moderate risks on a daily basis. With normal photodependent varieties I would tell you that it is better to water with more water, and then wait until it has dried before watering again. With autoflowering varieties we prefer to water with less water but more often.

We have to take into account what we saw before, the size of the pot in proportion to the size of the plant is the key factor to determine how much water is needed at any given time.

As long as the whole surface of the pot is not moistened there is no problem with the oxygenation of the substrate. No matter how much we water in the central part, around the stem, there will be no problems because the earth continues to oxygenate at the edges. But when the whole pot is moistened it is better to wait until it dries a little before watering again, as it is not good for the substrate to remain soaked for a long time.

8. High levels of E.C. in flowering.

They take in higher levels of nutrients than most normal strains, but that doesn’t mean you can give them all the fertilizer you want. During growth it doesn’t need more than the root stimulator and microlife, so when flowering arrives the substrate is still quite clean of salts, that’s really good.

When the first pre-flowers begin to appear we start to give them the flowering stimulator, at that time it is also good to start with the flowering base fertilizer. During this phase the plant continues to grow, but still does not need high doses of nutrients for its potent development.

Once the plant stops growing and focuses on fattening the flowers it is time to begin to provide fattening flowering, along with the stimulator and fertilizer base of this phase. Now they admit E.C. doses of 2.0 and even more, right at the key moment of cultivation.

image of a cannabis plant eating*

9. Photoperiod of more than 15 hours of light daily in indoor cultivation.

We know that automatic varieties do not rely on hours of light and darkness to grow or bloom. These plants can be maintained throughout the growing cycle with the photoperiod of growth, that is, 18 hours of light and 6 hours of darkness.

This is a great advantage, because normally the more light the more production, so being able to flower with more than 12 hours of light will increase the weight of the crop. We must also bear in mind that the greater the photoperiod or light intensity, the greater the need for irrigation and food. The same variety cultivated with 12 hours of light or 20 hours of light is going to eat very differently, so it is necessary to combine it with a greater diet when cultivated with more hours of light.

10. Choose the best outdoor season for your crop.

As it happens indoors, autoflowering varieties grow and produce more when they have more hours and intensity of light, in this case the sun. We do start from the premise that when the sun shines most during the year it is at the beginning of summer, we already know when it is the best season for the outdoor cultivation of automatic flowering strains.

The ideal is to germinate the seeds one month before the summer solstice, which is almost the maximum number of hours of light, so that the flowering coincides with the best time of the year.

If you do several outdoor autoflowering harvests each year, it’s best to start the first one in early spring. This one ends almost at the end of this season, and at that time we germinate the second round, which will be cut almost at the end of summer, and if the weather in your area is not too harsh in autumn, you are still in time to germinate a third one.

The size of the pot must be adapted to the season, this means that a summer crop will always need more volume of pot than a crop in spring or autumn. But outdoors it would be nice to put at least a 5,28 US gallons, from then on, depending also on the discretion you need.


image of an infograph that represents the best way to cultivate autoflowering varieties*


The most important requirement to achieve the highest production with autoflowering is to get a large root system as soon as possible. From our point of view it is better to transplant, as long as it is done without causing stress to the plant. The final flowerpot indoors should be more than 2,64 US gallons, and outdoors more than 5,28 US gallons. The photoperiod indoors more than 15 hours of light, and continuous watering with little water.

Keep these tips in mind when you are going to cultivate autoflowering plants, follow them and then tell us how it went, and if you liked this article you do us a favor if you share it.??

Are you going to plant autoflowering seeds and not sure how to do it? ⭐ Do you want to get the best performance with autoflowering? ✨ Check this out.