When to Repot Your Houseplant?
Knowing when to repot your houseplant can feel pretty overwhelming. Every plant is different and has specific preferences, and if you've never repotted before, the process can feel quite intimidating!
Understanding when your plant needs repotted is something that can be learned over time during the process of getting to know your plant. While there are no hard and fast rules, there are some great guidelines that you can follow and then make your best guess.
Generally speaking, repotting isn't usually as time critical as we might think. Plants are forgiving and resilient, so taking a lesson from their book, we should be forgiving of ourselves as we learn to care for them.
Repotting vs Potting Up
These terms are often used interchangeably, but they mean slightly different things.
Repotting: Removing a plant from an existing pot, adding fresh potting mix, and then putting it back into the same pot.
Potting up: Removing a plant from an existing pot, and adding fresh soil and relocating it to a slightly larger pot. Most people use repotting to describe this, so I'll just use the term "repotting" moving forward.
Easy Repotting Guidelines
As mentioned, when to repot can vary on the specific plant/situation, but here are some general rules to help you get started:
Young Plants (one year or less): Repot (pot up) into a larger container every 6-12 months as the roots outgrow the pot.
Older plants (one year+): Repot (pot up) every 1-3 years into a larger container as the plant's roots outgrow the pot.
Once a year: If you don't repot or pot up to a larger container, refresh the top of the pot with a layer of potting mix to add fresh nutrients.
There are a bunch of scenarios where these general guidelines might leave you still asking questions, so let's dig a bit deeper (pun intended)!
Repotting Green Lights: When to go for it!
Roots are poking out from the bottom of the pot: Now, a few roots are generally okay, but this is your opportunity to look a bit closer before deciding. Gently remove the plant from the pot and see what's going on. If you're seeing more roots than potting mix, then it's time to move them to a larger home. If it's about 50/50 or less, you can get away with waiting a bit longer. Try this strategy if you see roots poking out of the top of the soil as well. If there's still room inside the pot, add some top dressing to the pot to cover those roots for the time being.
The plant completely fills out the pot: This means if you're looking at the top of the pot, you really can't see any soil because the plant spans the entire diameter of the pot.
They are top heavy and fall over easily: This is the easiest to notice in plastic or lightweight pots, but isn't as obvious if they are in a heavier pot.
Plastic pot bulge: This is really only apparent in plastic pots, but the pot will literally become misshapen and distorted because the roots are trying to burst through.
The pot dries out super quickly: This is harder to discern because watering needs change throughout the year. But if you're checking in with your plant on a regular basis, you will notice that they become thirstier and thirstier over time, and if that's the case, take a peek at the roots and see if they have outgrown the pot.
Repotting Yellow Lights: When to Pause and Investigate
It's winter: If it's winter and you want to repot your plant because it's not looking great, read this before deciding. There’s a lot of controversy around whether it's okay to repot in winter, but let’s start with the reasons we have been advised to not repot in winter: Avoiding Undue stress on the plant because they are dormant. Dormancy, which is a natural part of a plants lifecycle (we all need rest, right) which can happen when the environmental conditions change (colder temperatures, drier air, less light) and the plant slows/stops growth to conserve energy.
Outdoor plants in cold climates like here in Canada go fully dormant in winter. But indoors, that’s not necessarily the case. If you don’t make winter adjustments to your plant like adding a grow light or a humidifier, they will likely react to the change in their climate- less light, lower humidity, and possibly cooler temperatures depending on where they are in your home. Although those plants might slow their growth, look a bit paler, have crispy brown tips or shed some leaves to conserve energy, they likely aren’t fully dormant because their soil isn’t frozen and their roots are still growing and bulking up for when spring comes.
If this sounds like the case for your plant, then repotting isn’t going to fix those issues. Instead you can adjust their environment by: providing more light, being careful to not overwater and only give water when their pot has dried out to the plant’s preference, potentially add a humidifier, and make sure they are at least 6 ft away from a heating vent.
If this isn't the case for you, and your plant has one of more of the green light reasons above, go ahead and repot!
You suspect root rot: If you're in the early stages of root rot, you can usually get away with pulling the plant out of the pot (soil still intact) and allowing it to dry out. You should also add more light as soon as possible. In this case, you don't need to repot. If the root rot is more advanced, you might need to do a full repot. This is a detailed process so I'll cover more about this in a later post.
Repotting Red Lights: Don't repot right now
Your plant is flowering: We want to keep those blooms as long as possible! Repotting will cause stress and the blooms will likely stop.
Your plant has pests: If your plant is infected with pests, it's already stressed, so we don't want to add extra stress by repotting it. Houseplant pests can be treated without repotting, so quarantine your plant away from other plants, take the steps to identify the pest you have and treat them accordingly.
I'm often asked if we should repot when we have fungus gnats since they live in the soil, and the answer is almost always no. This is because fungus gnats are a sign that you need to modify your watering practices, so if you repot and don't change how you water, the problem will likely start again with the fresh soil. The only time I would make an exception is if you bought a new bag of potting mix, used it, and then realized the bag was infested with fungus gnats (which unfortunately, happens occasionally).
Your plant has a disease: Same reason as above, if the plant has an issue, they are already stressed and it's better to treat them than repot them.
You just brought them home: I know plenty of people who repot their houseplants immediately upon bringing them home. And if it works for you, then go for it! But I wait at least a month after bringing them home because the relocation from the nursery to plant store to my house is already a series of stressful events, so I want to give them time to adjust before repotting them.
I hope these tips help take some of the mystery out of when to repot. Just remember to look closely and observe your plant, make your best guess, and don't stress too much about repotting – plants are tougher than we often think!