Selecting Pots and Adjusting pH for Your Indoor Grow

This article on pots for your cannabis grow is part of a series.
You can catch the rest of FAB’s Indoor Grow Guide at the link below!

A Guide on the Little Bits and Bops of Your Grow-Op!

Want to keep your beautiful plants happy and healthy, inside? You’ll need to make sure of a few things.

First, ensure your soil is moist at all times. Allow your plants to take in oxygen, which helps plants grow faster, feeding them the right nutrients. Check their PH levels, and adjust accordingly. Your choice of pot will affect all of these factors.

Are you struggling to decide which pots are right for you? It’s important to consider the context of your grow. You want to give your cannabis the best root growth and structure that you possibly can. Picking up pots that will help with this is important.

Potting Options

You can use many different types of containers for your cannabis. We are simply offering a few suggestions for beginners. These are generally the common pots used for the purpose of growing cannabis indoors.

Standard Plant Containers

These are typically made of clay. They are easy to find at any gardening store. You can also find them at Bunnings.

The biggest issue with these pots is their weight: they’re a bit heavy. It can be difficult to move these buggers around. They do retain water really well, though. This could be a positive or negative, depending on your grow.

Air Pots

These pots are made from plastic. They have holes all over the sides, allowing for greater aeration and faster drainage.

They’re also very cheap, and easily purchased on E-bay. The pots come flat-packed; you assemble them yourself.

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Personally, I love these pots. You can even use the holes to help train your plants. They do drain very easily, requiring your plants to be well-irrigated. On the upside, it’s harder to over-water your plants!

Fabric or ‘Smart’ Pots

These pots are similar to Air Pots. Their fabric design allows the roots to receive more oxygen, and provides better drainage.

‘Smart’ pots do dry out quicker than your average clay pots… but they’re super cheap, very effective, and easily purchased online for cheap on eBay.


Just take a bucket and put some holes in the bottom for drainage.

A bucket will help you hold onto water longer than Air and Smart Pots. They’re like a clay pot, but much cheaper. If you’re growing large plants, buckets can be a great choice!

Hydroponic Containers

If you’re considering setting up a hydroponic growing operation, with a water pump and a reservoir of water, you’ll be looking for hydro containers. This is where your cannabis will sit in water.

Typically, you use baskets with clay balls as a soil medium. We don’t recommend this setup for beginners.

How to ‘Stop Getting Wet’

When picking your pots, you also need to be looking for a saucer or tray for them to sit on top of.

Sitting your pots on top of saucers will allow the water to build up within the saucer itself – rather than all over the floor. You can find saucers at Bunnings or onE-bay.

Pro Tip: When picking a saucer or tray… find one that is slightly bigger than your pot. If your pot is 25cm in diameter, find a saucer that’s a bit over that – 30cm.
You will need to keep this size in account when considering the size of your grow tent – you want all of your pots to fit, after all!

It doesn’t matter too much if they saucer or tray is made from either plastic or clay – just so long as you have them. It will make your growing experience significantly less messy, and help you retain water.

What Size Container Should I Use?

The size of your container/s will depend entirely on how big you want your plants to get, as well as the size of your grow tent.

Ideally, you want to figure out the surface area you can cover with your pots inside of your grow tent.

If your grow tent is 1 x 1 metres, you could potentially hold nine 30cm diameter pots, in a 3×3 grid. This gives the plants a little wiggle room from each other…

You could also place 4 plants in 40-45cm diameter pots. Typically, your yield isn’t factored by how many plants you have, but the area in which they grow. So having 4 bigger plants can be easier to manage than 9 smaller plants. This decision is up to you, however. For a beginner, I would recommend bigger plants in bigger pots.

A general rule of thumb is to provide 8 litres of soil per 30cm of plant height.

If you want 1-metre-tall plants, dependent on your grow tent… you probably want 24 litre pots.

If you’re growing in coco coir… you could grow 1 metre tall plants in 13-15 litre air pots, without much worry. You’ll just have to water them a little more regularly.

Pick larger pots, where you can. Pot size determines how big your plants can get.

What About Watering? What About pH Levels?

Well… first thing’s first. You’ll need a watering can! You can pick one up at Bunnings, of course.

I recommend grabbing at least a 9 litre watering can. Not too big, not too small; your plants need a lot of water!

Next, you need to know how to feed your plants nutrients through water. Read our guide to Nutrients for more.

…and now, the most important part of watering…

Checking and adjusting pH to give your plants optimal nutrient absorption. Cannabis plants thrive best in water that is between 5.5 – 6.5 pH – if you’re growing in coco-coir.

If you’re growing hydroponically, I would suggest aiming for a pH of around 6.0. If you’re growing in soil; best to work at around 6.0 – 7.0 – a pH of around 6.5 will make your life very easy.

Remember, though; you don’t need to be exact. Just keep your pH within range.

How do you Check and Adjust pH?

It’s quite simple. You’ll need to purchase a pH meter. You can pick one up on eBay for just $15 with free shipping. To use the meter, you need put it into your watering can, and see what number it reads out. You can also pick up a soil meter, in order to check your soil’s pH, oneBay for around $30.

Adjusting your pH will require you to purchase some PH down and pH up. Realistically, you will only need one of these, once you know what the pH of your water supply is. You can grab them on eBay for $25 with free shipping.

“I Have ‘The Tools’… How Do I Use Them?”

Here’s how:

  1. Add your nutrients and/or supplements to your water, then give them a mix. It can help to put your nutrients into a small cup of water, then mix them all around in the cup, and put the cup in your watering can. Give the mixture a good stir.
  2. Test your pH. Is it ‘on point’? If not, it’s time to adjust your pH.
  3. Add pH up or down as needed. Follow the directions on the bottles; they will tell you how much of the solution you need to add to your water.
  4. Retest your pH level. Make sure it’s within the proper range… if not, keep adjusting.
  5. Water your plants! It’s important when watering your plants to allow for 20% runoff outside of the pot (unless your plants are very young)
  6. Test the runoff water for its pH. If the levels are not within what you require, you’ll need to adjust your pH again.
Once you figure out how much pH up/down you need to use to adjust your water, it will likely be the same amount every time… assuming it’s from the same water source.

Quick Tips for Watering

  • Nutrients: Don’t use too much. Using less is better, as you can always add but never take away. Start with a half dose strength of nutrients, and work your way up.
  • Never mix nutrients directly with each other. Always add them into water.
  • Add “micro” nutrient to water first – if you’re using a 3 part nutrient solution.
    • Read the instructions on your nutrients for more information.
  • pH can always change. This is nothing to worry about, for as long as you are remaining within the guidelines.
You can learn more about adjusting your pH onGrow Weed Easy – An excellent online resource for growing cannabis.

Main Article: A Guide For Growing Cannabis Indoors in Australia

Joe Lagrasso

Author: Joe Lagrasso

Joe is a dreamer, entrepreneur and an all-around good guy. He wants to connect the Australian Cannabis community from businesses to consumers.

Joe Lagrasso
Joe is a dreamer, entrepreneur and an all-around good guy. He wants to connect the Australian Cannabis community from businesses to consumers.


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2 years ago

How often should you water your plants and how often should you feed them nutrients?

2 years ago
Reply to  Tiarna

You should water and feed them every other day. Pay attention to pH levels.


[…] To find out how much soil/coco you’ll need, be sure to read our potting article. […]

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