3 gallon or 5 gallon pots for autoflower

Get the Right Size: 3 Gallon or 5 Gallon Pots for Autoflower

Growing cannabis doesn’t always mean a trailing field with beds and beds of plants. You can also grow in pots if you don’t have enough space.

However, choosing the right size pot isn’t duck soup. 

So, 3 gallon or 5 gallon pots for autoflower?

3 gallon pots are generally best for indoor growing. On the other hand, if you have enough space then you can prefer 5-gallon pots. However, for autoflowers 3-gallon pots are more appropriate than 5-gallon pots. Because most of the time 5-gallon pots cause soil and nutrient waste.

I understand your mind must be lurching with all the questions. No worries! I’ll give you a tour of all the aspects in the next sections. 

So, let’s dip in and until the horizon, may the force be with us-

Quick Comparison

Be it yielding 1 pound from 1 or 4 plants, the size of your pot always matters. However, there are some things you need to take into consideration before choosing a pot.

Let’s have a comparative bird’s view on these two different sizes of pots here- 

Factors3 Gallon Pot5 Gallon Pot
Dimensions 11.8×8.3 inches14×10.2 inches
Plant length Upto 3 feetUpto 5 feet
Veg period Short Long
PriceShop Now Shop Now

You might be asking how we ended up comparing on this grounds. Fret not! Everything will be clear as daylight as we’re moving toward the in-depth discussion.

Let’s continue…

3 Gallon or 5 Gallon Pots: Which One to Choose?

Well, it’s basic knowledge that the size of your container will weigh the size of your plant. That’s why depending on your requirement you should choose your pot.

Generally, you’ll need a gallon of pot for one foot of plant. Because a plant grows as much as the space of the pot. Once they outgrow the pot, it won’t have any more space.

So, let’s see how much space you’re getting with a 3 gallon and a 5 gallon pot-

What are the Dimensions of the Pots?

You see, the actual volume of a 3 gallon pot is around 3.9 gallons. And the dimensions of this size are around 11.8×8.3. 

So, normally you’ll be able to grow a 1-3 feet plant in your 3-gallon pot. However, if you’re adding the proper fertilizer with your soil then you might yield more than usual.

I generally use the following grow fertilizers to get the most out of my plants-

On the other hand, a 5 gallon pot’s actual volume is around 6.8. And the dimensions of these pots are around 14×10.2″. 

Now the question is, how big of a cannabis plant can you grow in a 5 gallon pot?

Source: https://hc-companies.com

Well, cannabis can get very large in a bigger container. So, in a 5 gallon pot, your plant can grow up to 6 feet. 

However, if you’re working indoors then you might not have enough space. In that case, choosing the 3 gallon pots would be wise. But if you have larger space then you can go for the 5 gallon pots.

What’s Your Room Layout? 

Your room’s layout should be taken into consideration as well. 

Suppose, you’re using an iPower 80″x80″x78″ grow tent. And you’ve got 240W LED grow lights with it. In this setup, you can yield enough autoflower using a 3 gallon pot.

So, my point is, your grow room or tent setup plays a big role here. You can get the same yield using a 3-gallon that you usually got with a 5-gallon. Just choose the better lighting setup while installing your air-cooled hood.

Some great-quality MH/HPS lights that I’ve used so far are suggested below-

Also, cannabis grows nicely in cloth grow pots. So, if you’re an indoor grower, getting a 3-gallon fabric pot would be great.

Some 3-gallon fabric pots that I absolutely loved using are-

Moreover, fabric pots help to keep the root of the plant in the middle. It’s definitely helpful to save your plant from getting root-bound.

Now, let’s see which grow pots need what kind of maintenance.

Moving forward-

How Much Water the Pot Would Need?

Source: https://www.autoflowering-cannabis.com

Well, watering your plant mostly depends on the pot’s size as well. So, if you’re getting a 3-gallon pot then you don’t have to water much. 2-3 cups of water will be sufficient to soak the soil and roots.

On the other hand, as 5-gallon pots are bigger it’ll take more watering. Probably around 5-6 cups depending on your soil quality. However, too much soaked soil might end up damaging your plant’s roots.

In this case, I use the following soils interchangeably. 

These soils’ light aerated texture doesn’t hold water for so long. Hence, no chance of damaged plant roots.

Now, do you know how big of an auto flower can you actually grow? If not then let’s learn about it right now- 

How Big of a Plant Can You Grow?

Normally, auto-flowering strains don’t need huge space to grow. So, their growth is somewhat limited to 2-3 or 5-6 feet.  

Moreover, they’re usually prepared to harvest in two months. Sometimes it’s earlier than that. Therefore, assessing everything, getting a pot of more than 3-gallon would be a waste of soil.

And if you have a small space then 3-gallon pots would be perfect. Furthermore, your autoflowers can also be trained with low stress training. In this way, you’re getting a bigger yield with smaller pots in a tiny room. 

Moreover, if you’re an indoor grower then you can easily put 9x 3-gallon pots together. Whereas in the same place you’ll be able to place 4x 5-gallon pots together. You see, in this way again with smaller pots you’ll be getting more strains.

How Long is Your Veg Period?

Now, if you’re aiming for a short veg, for example, 2 months then 3 gallons are great. When I was looking to harvest in 1.5 months I used the Real Growers Recharge with my pot soil. It helped the plants grow quickly and I got to yield bigger. 

Hence, I believe, for a short veg a larger pot would result in a waste of money and nutrients. 

However, if you’re aiming for bigger plants and longer veg then by all means aim for the clouds. At this point, you can prefer the 5-gallon pots.

Which Types of Pots Would be Better Options?

Here’s a million dollar tip…never grow your auto-flowering seeds in the Dixie cups. Because it’ll affect your plant’s roots and they’ll become root-bound.

However, you can choose any of the following pots or bags. Be it a 3-gallon pot or 5-gallon pot, you’ll surely love the options we’re suggesting here-

Have you chosen your preferred pots yet? If not, then let’s go ahead to the final call section. 

What’s the Final Call?

Source: https://balancemmc.com/

I’ve personally had the best experience with my 3-gallon pots. Though I’ve also used 4” and 1 gallon pots for my autoflowers.

However, with time the 1-gallon pot plants got bigger. And eventually, I had to move them to the 3-gallon. 

On the other hand, I even used 5-gallon pots. But as I was growing indoors, 5-gallon took so much of my space. 

Now, let’s see the usage of 3-gallon and 5-gallon pots in a nutshell-


Is it okay to plant 2 cannabis in one pot?

No, you shouldn’t plant 2 cannabis in the same pot. Because cannabis doesn’t like crowds. Moreover, with time they might fight for nutrients.

How much soil would I need for my autoflowers?

Generally, you should mix all kinds of ingredients in your pot mix. So, try to start with 3 portions of peat moss and 3 portions of the compost. 

How long can an autoflower be?

On average, an autoflower grows up to 100 cm. The ultimate growth of your autoflower also depends on your pot size. And the environment you’re providing plants also plays a big role.


Hope you chose one between 3 gallon or 5 gallon pots for autoflower.

However, with the right environment and all the necessary supplies, a 3-gallon pot is enough. But if you’re capable of managing bigger pots then go for a 5-gallon pot.

Happy gardening!

Leave a Comment

Your email address will not be published. Required fields are marked *