9 Mistakes To Avoid When Growing Autoflowering Cannabis
Autoflower cannabis has always sparked debates among growers in the cannabis community. Due to a dearth of knowledge or experience, many growers avoid growing autoflowers. Beginners are expected to only grow photoperiod plants, and while the fear of something new and unexpected is understandable, you might discover something more amazing if you just try.
Autoflowers are really easy to grow but there are basic guidelines you should know, just like when growing other plants or vegetables. All plants are different and even though you can successfully harvest the first time you grow cannabis, there are common mistakes that are better to avoid.
If you’re new to autoflower growing and are looking for an autoflower grow guide or want to know how to grow autoflowering strains, here are a couple of tips to have you growing in no time.
1. Knowing the basics
To set things straight, let’s begin by saying that autoflowers are really easy to grow. In fact, beginners can try growing autoflowers with little to no experience as long as they understand the basics 1 .
And this is true for all plants. Can you expect to grow tomatoes if you’re clueless about using nutrients? Or, can you harvest cucumbers if you don’t even know when to harvest them? No? Similarly, autoflowers need you to follow a few basic guidelines like other plants, and you’ll do just fine if you take the time to understand them.
After all, a plant that gives you lip-smacking buds in just 2 months deserves some research, eh? Autoflowers may scare you at first, but if you avoid a few common mistakes, you’ll harvest much more than you can imagine, and it only gets better.
2. Time it right
Timing is everything if you’re planning to grow autoflowers outdoors. Since autoflowers don’t depend on light to flower, you don’t need to worry too much. But, planting too early will generate smaller yields and planting too late affects yields too.
Frost must be avoided at all costs. Typically, most growers begin planting when spring is just around the corner. Depending on where you live, you can plant the seeds as soon as the frost clears. If you reside in a location that doesn’t receive any snow, go ahead and plant when the temperatures range between 22°C to 28°C (71°F to 77°F).
Bigger plants can tolerate much higher temperatures but tender seedlings will succumb to extreme temperatures. Remember to avoid rainy seasons since the plant doesn’t receive too much light. Of course, the timing doesn’t matter if growing indoors, so sow those seeds whenever you wish!
For beginners, germinating the seeds is an important part of the entire process. To get better results, soak the seeds in plain water for at least 24 hours and wrap them in moist paper towels for a day or two. Use a ziplock bag to store the towels.
It’s important to keep the towels moist because the seeds can rot if there’s too much water. Similarly, the seeds won’t sprout if the towels are completely dry. Don’t make the mistake of directly planting the seeds, especially if you’re doing it for the first time. Once the seeds show a tap root, plant the seeds in the final container.
Despite having to keep the seeds in damp paper towels, make sure they are not completely wet, too much water can rot the seeds. The best way to identify this is by smell if the paper towels start to smell like mold, immediately take them out and change the towels.
Depending on your experience, you can also germinate your seeds directly in the medium, just make sure you’re not overwatering it because you can end up drowning your seeds. As you can see in the video, germinating in the soil is easy and doesn’t require anything extra, just be careful and you’ll see a seedling coming out of the ground in a couple of days.
4. Choose the right medium
Growing plants in hydroponic setups seem very cool, but soil is your best bet if you have no experience. Avoid using clay soils that clump up because autoflowers thrive in well-aerated soil. A soilless medium of equal parts of peat moss or coco peat, perlite, some airy soil, and sand is the best potting mix for autoflowers.
If you don’t want to bother about fertilizing at all, you can even try growing autoflowers organically. There are various ways to make your own organic soil, but you can buy some in your local store to start with. Organic soil is premised with nutrients, so it’s ideal for someone that doesn’t have a lot of time. For growers that don’t mind putting in the efforts, composting and building super soil is the best soil mix for autoflowers.
If growing outdoors, till the soil well and amend it with organic nutrients to produce a happy, healthy plant. But, no matter what you do while growing indoors, stay away from old used soil or sterilize it before you plant seeds to prevent diseases.
5. Choose good containers
Please don’t stuff seeds in plastic containers that make life hell for the poor roots. Use porous containers such as fabric pots or even Airpots to help the plants grow as much as possible. Autoflowers are typically small, but they need containers that are at least 5-8 liters in size.
Bigger autoflowers need bigger containers, so make sure you check the description before purchasing seeds. Root aeration is often overlooked, but it’s an important factor in determining your yields.
The appropriate pot size can also help you control the height of your cannabis plants, usually, a 12L pot will allow your plant to develop to its maximum, an auto in a 7L pot will grow up to 70cm and in a 3L pot will grow around 40cm.
6. Do not transplant
It’s important to start autoflowers in their final containers rather than planting them in smaller ones and transplanting them later. Sure, growing cannabis is like growing tomatoes, but autoflowers have a limited time period and can’t afford to lose days while the plant settles and searches for roots.
Some growers use small plastic cups to plant seeds. While this method may work with photoperiod plants, it’s not recommended for autoflowers. If you’re already committed the mistake of planting them in small containers, try to transplant the plant only when the soil is moist. If the soil is too wet, the roots tend to break, and if it’s too dry, transplanting becomes a pain.
Of course, experienced growers do transplant autoflowers but it’s not really necessary.
7. Over and under-watering
Most plants die if you over or under-water them. Yes, autoflowers need water to grow, but it’s critical to supply it only when the plant needs it. It’s obvious that the timing is important even when the plants need water.
A way to check if the soil is dry is to use your index finger and stick it in the soil, if it comes out moist then the soil is still humid, although by doing this you won’t be able to know if the bottom is still wet so in order to get the timing right, lift the pots and check the weight.
A dry pot will be easy to lift whereas container with lots of water will be heavy. The trick is to not let the soil go too dry or too wet, so water the plants only when the pot isn’t too heavy or light.
8. Overfeeding and underfeeding
Nutrients play a big role in growing autoflowering cannabis strains. Autoflowers are compact, so they don’t need loads of nutes in order to survive. In fact, autoflowers grow best when light fertilizers are used. It’s also important to feed the right nutrients at the right time.
Macro and micronutrients
For example, cannabis needs more nitrogen in the vegetative stage. In the pre-flowering stage, nutrients with more phosphorous are preferred, and in the flowering stage needs a lot more potassium than nitrogen or phosphorous.
If you’re wondering what the term “N-P-K” printed on fertilizer bags means, it’s nothing but Nitrogen-Phosphorous-Potassium. The plants also need other micronutrients along with calcium and magnesium, so it’s extremely important to get the dosage right.
Don’t make the rookie mistake of using Miracle Grow or any other fertilizer meant to grow vegetables. Autoflowers will grow well even if you do that, but since they have special needs, you might as well stick to nutrients that supply everything. From humic to fulvic acid to enzymes, you can do a lot to make the plants perform to the best of their potential.
Talking about nutrients, some growers try to make their own nutes. While it’s completely okay to do so, you should avoid doing it if you’ve never done that before. Nutrients are expensive and it’s tempting to make your own, but try to attempt that after you’ve gained some experience.
Why? Because cannabis plants require a good blend containing all micro and macronutrients in exact concentrations to thrive. It’s not as simple as diluting a random fertilizer and feeding the plants. You not only risk burning the plants, but the yields will suffer drastically since the plants have no time to recover.
So, if it’s your first time, stick to commercial nutrients. And, the topic on nutrients is incomplete if you don’t talk about pH. Depending on the medium 2 you choose to grow, the pH must be regulated accordingly. Cannabis plants love acidic soil, so the pH must be maintained between 5.5 to 7 in both soil and hydroponic setups.
If the pH drops below 6, the roots will not be able to intake vital nutrients such as magnesium, calcium, and phosphorous. Similarly, if the pH is too alkaline and goes above 7.5, the roots cannot take up micronutrients like copper, manganese, boron, etc. It’s very important to regulate the pH at all times to prevent nutrient deficiencies.
Here’s a quick table to help you understand pH better:
|Nutrient||Ideal PH Level for Absorption|
Sometimes, it just so happens that the plant refuses to respond even if you’ve done everything. In such cases, flush the plants with lots of water (at least double or triple the size of the container) to reduce any nutrient or salt buildup so that the plants can breathe again. Flushing is typically done at the end, but it doesn’t hurt the plant even if you do it in between because it reduces buildups to a good extent.
Some growers also flush during the pre-flowering stage, when the plants are transitioning from the vegetative into the flowering stage so they can start feeding from zero, as said above, this won’t hurt your plants but should be done properly.
9. Harvest at the right time
You’ve come all this way, and the end is almost near, so don’t screw this up now! Now you’re probably asking “how to tell if my autoflower is ready for harvest?” Well, after you’ve put in all the hard work, wait for the right time. Growers use microscopes to check the trichomes that usually indicate the right time, but you can harvest when at least 50 to 70 percent of the pistils are amber in color.
If you wait too much, the buds tend to produce a couch-lock effect leaning more towards the Indica side while buds harvested too early generate unpleasant psychoactive effects. Also, the main colas ripen faster than the lower portions of the plant.
Often referred to as popcorn buds, the lower portions stay small. However, harvesting the main colas and leaving the popcorn buds on the plant for a week more will increase yields dramatically. Be patient, and let Mother Nature do the rest for you! If you avoid these common mistakes when growing autoflowering cannabis, you’ll soon be rewarded with potent resinous buds that will last a long time if stored properly.
10. Frequently Asked Questions About Autoflowers
What’s the average autoflower size and how tall can they get?
Most autoflowers reach a height of around 50-100cm but a plant’s size depends on the genetics and growing conditions. Also, all strains are different so you will find Sativa and Indica-leaning autos; Most Indica hybrid autoflowers will stay around the 80-120cm mark but Sativa-dominant autoflowers can reach up to 175cm tall.
Can I grow my auto on my window sill?
Yes, you can, although it’s not recommended if you want to get the best results possible but if this is the only way you have, make sure your plant gets at least 4-6 hours of direct sunlight a day and that you’re using at least a 10-liter pot.
Do autoflowers grow normal or smaller because of the Ruderalis genes?
The size of an autoflower can be influenced by several factors, genetics being the main one. More modern autoflower breeders breed their genetics to contain as little as Ruderalis genetics as possible, focusing on the more appealing characteristics such as size, structure, potency, and yields.
But when compared to a photoperiod plant, an autoflower has a limited lifespan so things such as stress, damage, or a bad environment can ultimately affect your auto’s height, so it’s ideal to provide optimum grow conditions to get the best results possible.
When is the best time to plant autoflowers outdoors?
This solely depends on your climate, you need to remember that autos prefer dry sunny days so if you’re planning to have just one grow cycle, you can start them 1-2 weeks into Summer, and if you’re planning to have 2 harvests, start the next one right after finishing the first one.
What yield can I expect per autoflowering plant?
The yields depend on genetics, environment, stress, growers skills, and etc.. But in general, you can expect between 50-110 grams per plant.
How long will it take for my auto to start flowering?
In general, autoflowers stay for 4 weeks in the vegetative stage, so about 4 weeks. Then your auto will start developing flowers for 3 weeks, and fattening up the buds for the last 3 weeks.
This may vary according to the genetics and growing environment, have in mind that it’s just to give you an idea of what to expect, some autoflowers may take less and others take longer.
Yes, you can, although it’s not recommended because it can affect the yields. To prevent shocking your autoflowers and consequently affecting yields, it’s recommended to transplant 7-12 days after germination and if possible, use rooting cubes to prevent damaging the roots.
Can you grow autoflowering cannabis in a greenhouse?
Of course you can, you can grow autoflowers in a greenhouse all year round as long as you keep the inside temperature to a minimum of 15°C and there’s enough ventilation, airflow, and sunlight.
11. In conclusion
Autoflowers are suited for beginner growers but it’s crucial you know the basics if you want to have a successful harvest the first time you grow cannabis, although you can learn as you go, it can be disappointing if you waste time and money, and end up with nothing to smoke.
Now that you know the basics and what to avoid, you’re all set up to start your first autoflower indoor grow.
If you’ve never grown cannabis before and are planning on growing our autos, feel free to ask us anything in the comment section below!
This post was most recently updated on January 25, 2021.
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