When your plant shows signs of being root-bound, it’s your cue to upsize its pot. Not doing so is detrimental to your plant, as:
- there is not enough room for the rootball to grow to support a larger plant; and
- there is insufficient soil to support your plant’s nutritional needs.
Both reasons cause stress, slow growth and an undernourished plant. As a result, you may notice yellowing or wilting leaves, or drooping stems. Eventually, the stress and malnourishment will lead to plant decline.
In this article, we’ll walk you through the steps to repotting a root-bound plant. There are 2 steps in particular that some people forget. So make sure you follow the steps to a T!
In this case, I’m going to repot a root-bound peace lily…. though the steps are applicable to any houseplant! 🙂
Determining if your Plant is Root-Bound
Before we jump into repotting steps, first determine if your plant is root-bound. Now, technically you can’t 100% know whether a plant is root-bound unless you unpot it and examine its roots… but there are a couple of tell-tale signs we can use as good indicators that we should proceed.
Ask yourself the 4 questions below. If you answer YES to any of them, chances are that your plant is root-bound.
- Look under the plant’s pot. Do you see any roots peeking out of the drainge hole?
- Do you see any exposed roots growing on the surface of the soil?
- Does your Peace Lily seem insatiably thirsty, making you feel like it can’t get enough water no matter how much you water it?
- When watering, does water drain through the pot immediately, without being absorbed at all?
How to Repot a Root-Bound Peace Lily
OK, now that we know that your plant needs to be repotted, let’s walk through how to do it. People often forget steps 1 and 3, don’t let that be you! Doing so WILL hurt your plant.
The best time for repotting is Spring, as the warmer temperatures and more sunlight help your plant recover after repotting.
1. Water your plant 24 hours before repotting – Don’t SKIP THIS STEP!
If you’re anything like me, you want to solve the problem NOW and don’t want to wait 24 hours. We know, we know.
But this step is important to help your plant dislodge from its pot. Ever heard of transplant shock? Avoid stressing your plant out too much by NOT skipping this step. 🙂
Water deeply and thoroughly, so that the soil is completely saturated for maximum effect.
2. Unpot the Peace Lily.
If your plant is in a plastic pot, you can squeeze the sides and gently dislodge the plant. Try not to pull on the stem too hard. You can also place the pot on its side or upside down, using gravity to help you.
On the other hand, if you’re using a ceramic or hard container, use a sterilized knife and run it along the edges of the pot to help it wriggle free. (To sterilize, dip the knife for 45 seconds in 70% isopropyl solution.)
When unpot, a root-bound plant has roots that are warped to the shape of the container, like so.
3. Loosen the roots. Don’t SKIP THIS STEP!
Loosening the roots is important to encourage roots to spread out and draw nutrients from farther ends of the pot, and to better anchor your plant. If you skip this step, roots will continue growing in a dense, tangled circle…. undoing the benefits of repotting!
To loosen the roots,
- Use your fingers and gently work your way through the root ball from the bottom to the top.
- Gently free any compacted soil, and untangle the roots. This should feel similar to untangling matted hair.
If the plant is severely root-bound, you can also soak the rootball overnight in a bucketful of room-temperature water. Stir in a teaspoon of seaweed extract or epsom salts, which helps break down the compacted soil. 🙂
If after all of that, you’re STILL struggling with loosening the roots, it’s okay to make a couple of vertical cuts to the sides and bottom of the rootball. Use a sterilized knife and cut 2-3 inches (5-8cm) off the roots.
Cut away just enough to “break” the condensed mass of roots, and start loosening the roots with your fingers.
4. Trim off any damaged roots.
Now that the roots are loosened and exposed, take the opportunity to snip off any damaged roots.
In most cases, you SHOULDN’T spot any damaged roots, but its good practice to check. Damaged roots are mushy, soft or brown, and in extreme cases, may smell bad too.
On the other hand, healthy roots are white and firm. 🙂
Since damaged roots cannot heal, your best bet is to trim these off to avoid infecting healthy roots.
5. Choose a new pot and add Fresh potting mix.
When choosing a new pot, upsize by just 2 inches (5cm). Having too large of a pot will lead to overwatering, as there is TOO MUCH unused soil that will inevitably hold on to too much water.
We also like using terracotta pots as their porous material allows for airflow to the roots. Additionally, it helps water to evaporate quickly from its surfaces. Both properties reduce the risk of root rot.
Whatever you do, be sure to choose a pot with drainage holes, to prevent “wet feet”.
It’s also important to repot your plant in fresh potting mix, as nutrients in any potting soil deplete over time. Generally, we like to fill fresh soil up to 1/4 of the pot, add in the plant, and top up the soil until the plant is secured in place.
What potting mix should you use? Well, consult our plant care guides and skip to the SOIL section. The exact potting mix we recommend varies depending on which plant you are growing.
If you have a Peace Lily, a mix of: 3 parts Miracle-Gro mixed with 1 part pumice is ideal.
That’s all folks! It’s not uncommon for plants to need some recovery time after repotting, as it IS a stressful event. During this time, refrain from watering for a few days to allow damaged roots to heal. You don’t need to change any other care conditions.
In a couple of weeks, your plant should have recovered as its settled into its new home. 🙂
Deborah is a plant enthusiast and founder of Gardening Collective.