How to Repot a Plant in 5 Simple Steps
Learning how to repot a plant is key to maintaining the health of houseplants and outdoor container gardens from one season to the next. Young houseplants tend to outgrow their container every six to 12 months, while older plants benefit from being repotted every few years. Outdoor container gardens also benefit from repotting to freshen the soil and provide room for expanding roots. Whether you are growing monstera or mandevilla, a jade plant or a lemon tree, learning how to repot a plant will help you keep your green friends looking their best.
What You'll Need:
- 1 pot (preferably one that's about 2 inches larger than the plant's current container)
- Sharp scissors or pruning shears
- Knife or flat trowel
- Potting soil with perlite
How to Repot Your Plant
1. Select Your Container
To allow for plant growth, select a new container that is 1 to 2 inches larger than the pot your plant is currently in. Pots must have drainage holes in the bottom to allow excess water to flow out of the pot, otherwise roots can suffocate and develop disease. If the container you wish to use does not have drainage holes, drill several holes about ½ inch in diameter. When selecting containers, avoid narrow openings—they will make it difficult to pot plants and limit water evaporation from the soil, which can cause pest problems. Finally, if you plan to leave a container outdoors during the winter, be sure to select a material that can withstand the elements, like fiberglass or stone. Terracotta pots contract and expand as they freeze and thaw, making them prone to cracking.
2. Buy the Right Soil
The success of a potted plant is rooted, quite literally, in a healthy soil. As with container selection, the most important consideration is drainage. Have you ever noticed small white balls in potting soil? This is perlite, a type of volcanic rock used to improve the aeration, water retention, and drainage of potting mixes. It may sound contradictory to want good drainage and water retention. There is a delicate balance to maintain here: letting excess water drain through the soil mix, while retaining enough moisture for the plants. Perlite and similar materials help maintain this balance. You can purchase pre-mixed potting soil containing perlite, or mix your own with equal parts sand, loamy garden soil, and perlite.
For outdoor containers, compost makes an excellent medium—it is loose, rich, and has high organic matter content. You may also want to mix a slow-release fertilizer into the soil (many ready-made mixes already contain fertilizer).
3. Remove Your Plant From Its Pot
Once you have selected a container and prepared your potting soil, it is time to remove your plant from its container. Root-bound plants may be very snug in their pots. If the plant is in a plastic container, squeeze the sides of the pot to loosen the soil. You can also cut through the side of a plastic nursery pot with scissors or pruning shears. To remove a plant from a terracotta or ceramic pot, slide a knife or flat trowel along the inside wall of the container to help loosen the plant. Then tip the plant sideways and shake it from its pot. Avoid pulling on the stems of the plant, as they can break. Instead, keep working the soil loose with a knife or trowel until you can carefully slide the plant out.
4. Loosen the Root Ball
A plant that has been growing in the same pot for a long time is likely to have roots circling the pot. Even plants you just purchased from the garden center may have circling roots. Before repotting the plant, we want to loosen up the root ball. Work your fingers into the soil and between the roots, starting at the bottom of the plant. Work the roots out of their coils and spread them out. Some of the roots may break in the process—don't worry. The plant will be much better off with its roots spread out, even if you break a few.
5. Place Your Plant in the New Pot
Once the roots are loosened, it is time to put the plant in its new home. Fill the bottom third of the container with the soil mix, then set the plant in the pot. Our goal is to set the plant high enough that the crown of the plant (where stems emerge from the roots) is about ¼ to ½ inch below the top of the pot. Add or remove soil beneath the root ball until you have achieved the proper height. Now you can fill in around the roots with soil while holding the plant in place. Gently push the soil down as you work to fill the spaces between the roots. You can also tap the pot on the table as you work to gently settle the soil. Fill the container to about ¼ to ½ inch below the top. Make sure to water plants right away. Plants are a little stressed after repotting, and we want to make sure they have plenty of water available.
How to Tell if a Plant Needs to Be Repotted
There are several key signs indicating a plant has outgrown its container. The most obvious are the roots themselves, which often grow through the drainage holes at the bottom of the pot when containers become too crowded. Sometimes, roots start to push the plant up and out the top of the container. Other indicators are plants that dry out more quickly than usual between waterings, or plants whose growth has slowed down considerably. Finally, plant size may tell you it is time to repot. When the aerial portion of a plant (the part above the pot) exceeds three times the size of its pot, it likely needs a larger container. The same is true if a plant becomes top heavy and easily falls over.
Slow-growing plants also benefit from occasional repotting to replenish the soil, even if they are not outgrowing their pot. These can be replanted in the same container with fresh potting soil. Spring is the best time of year to repot plants. These same steps can be followed for repotting both indoor and outdoor plants, so once you learn how to repot a plant, you can tackle any type of container planting.