It’s good fun to grow plants in your container garden but you also need to maintain them. One such maintenance is to check if the plants have outgrown their pots.
Plants can outgrow their pots or containers over time. The plant’s roots keep growing and extending into the pot. So they will cover the entire space once they grow big and become root-bound. You’ll need to transplant the plants to a bigger pot when that happens.
I’ve written details below on how you can figure out whether your plants have outgrown their pots and how you can repot them in a larger pot. You’ll also learn how you can prevent the plant from outgrowing its pot if that’s what you want to do.
How to know if a plant outgrows its pot?
There are some common signs your plant will tell you when it outgrows the pot. The plant’s roots will not have sufficient space to grow in the potting soil and circle inside the pot. This is when we say that the roots are pot-bound.
1. Check the drainage holes at the bottom
One of the most common signs is when there are roots coming out from the drainage holes at the bottom of the pot. This means the roots have covered the entire potting soil and are not finding space to grow further.
2. Check the potting soil
The other sign that your plant’s roots are pot-bound is if you find the roots pushing out of the potting soil at the surface. The roots don’t have space to grow downwards and so try to come out from the top.
3. Remove the plant out of the pot
An easy way to find out if your potted plant is pot-bound is to remove the root ball from the potting soil and check it. You will need to hold the base of the stem, invert the pot and gently tap it several times.
The root ball should slide out of the pot and if you see the roots are circling around the potting soil that’s a sign they are pot-bound.
4. Inspect the pot
You may find that the sides of the pot have developed cracks as some of the plants are strong and their roots try to break through the pot.
5. Inspect the plant
If the roots of your plant are pot-bound they will not have sufficient potting soil to get the required nutrients and moisture. This means the leaves will start to wilt or turn yellow. You will find that plant growth is stunted.
When you water the potting soil, you will find that the water runs out of the drainage holes fast without remaining in the soil. Or you may find too much water remains on the surface of the soil and does not get absorbed.
If the potting soil contains a large mass of the roots, you may find that the pot keeps falling over.
What to do when a plant outgrows its pot?
If a plant has outgrown the pot, the best thing you can do is repot the plant in a bigger pot. This will give the roots sufficient breathing space to continue growing and your plant can get healthy again.
There are a few steps you need to take if you choose to repot your plant which includes using a bigger pot.
1. Select a bigger pot
The obvious step is to pick a larger pot for the plant. But you need to be careful of the size. You don’t want to pick a pot that is too large.
Such a pot will hold more potting soil than the roots of the plant. This means when you water the potting soil, a lot of water will remain in it and you risk drowning your roots. This can lead to problems like root rot and other fungal diseases that may kill the plant.
You want to pick a pot that is just a size bigger than your plant. You can do this by measuring the diameter of your plant. Then pick a pot that is 2-4 inches larger than this diameter.
2. Fill the pot with fresh soil
Once you have selected the pot, you can place some paper towels or coffee filters to cover the drainage holes. This prevents the potting soil from leaking out from the bottom.
You want to fill the pot with potting soil so it becomes of the height sufficient to place your plant’s root ball.
3. Remove the plant from the pot
Now it’s time to remove the plant from the existing pot. You need to hold the base of the stem to protect the plant as you remove it.
Tilt the pot on the side and gently tap on it several times to slide the root ball out. If it does not slide out easily, you may need to tap it a bit harder against a hard surface like a potting bench.
4. Prune the pot-bound roots
Once you’ve removed the root ball from the pot, check the roots. If you find black, soggy roots, it means they’re infected by fungal disease and you need to cut them off.
If you find the roots are pot-bound, you can prune away a third of them from the bottom of the pot. You can even peel a small layer from the remaining roots.
Make sure to gently separate out the roots so they are no longer entangled into a mass.l
5. Place the plant in the new pot
Now it’s time to place the root ball in the new pot. Make sure the base of the stem is at a good height and just 1-2 inches below the rim of the new pot. You may need to add more potting soil at the bottom so it reaches this level.
Now you can add potting soil on the sides and top of the pot so it can cover the root ball. Make sure to water the potting soil well so the roots can adjust to the new pot.
6. Harden the plant in the new pot
Once you’ve moved the plant to the new pot, you should keep it in a shaded location away from too much heat and wind.
The plant will get stressed due to the cutting of the roots and moving to a new pot. You don’t want to stress it further by these elements.
You can gradually keep moving the pot in the regular location for a few hours every day. And after a week, the plant will be hardened enough so you can move it to this location.
You should also not add any fertilizer to the potting soil when the plant is recovering from such stress. I would suggest to only add such fertilizer after about a month of the repotting.
How to prevent a plant from outgrowing its pot?
There may be a situation where you don’t want to repot the plant in a bigger pot. Maybe you live in a small apartment and don’t have space for a bigger pot.
Maybe you won’t be able to carry the bigger pot into your apartment. Or your balcony won’t be able to support the weight.
In such situations, there are certain actions you can take to prevent your plant from outgrowing its pot.
Select smaller plants
There are certain plants like succulents or cacti that will not grow beyond a certain size. If you have space restrictions, growing such plants is a good option.
Some other small plants to grow in pots include fern, rosemary, cilantro, and pansies.
Prune the plant
If you prune the plant, you will prevent it from growing large. You will need to prune the top as well as the roots of the plant to do this.
You can use a pair of gardening pruners to trim the top of the plant and roots. Make sure you don’t prune more than a third of the plant as it could stress the plant.
You’ll need to take the root ball out of the potting soil to prune the roots. Make sure to only prune the smaller roots and leave the thicker roots as is.
Propagate the plant
There are some plants where you can divide them up by using propagation. You can cut off the stem or crown of such plants and grow another plant from it.
If you have such plants, you can just divide the plant and give the parts to your friends and family. This way you can continue to grow the smaller plant without the need to repot it in a larger pot.
Fact Checked, Written, and Published by Kevin Rodrigues
Kevin is the founder of Gardening Mentor, a website that aims to teach people to grow their own food in a limited space. As a self-taught gardener, Kevin has spent several years growing plants and creating gardening content on the website. He is certified in Home Horticulture and Organic Gardening from Oregon State University. He has a Post Graduate Diploma in Horticulture and Landscape Gardening from Mumbai University.
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