Repotting is an important part of keeping healthy houseplants. The best time of year to repot is in spring, before the new flush of summer growth. Some signs that you need to repot your plant are:
- Roots protrude from the bottom of the pot
- The plant stops growing or becomes limp
- The plant is root-bound or pot-bound
Many tropical plants like to be slightly underpotted, and unless you need to repot it because the soil is exhausted or the plant is suffering, there is no reason to do it early. An over-potted plant will focus on root growth at the expense of new foliage and flowers. Finally, some plants, such as bromeliads, will almost never need to be repotted. If a bromeliad sends out pups, or mini-plants, just cut these off near the base of the mother plant and pot them separately.
Steps for Repotting a Plant
If a plant is too large to repot, you can top dress the soil by carefully removing the top few inches of soil and replacing it with new compost. Take a look at the steps for transferring your smaller plants into larger pots.
Prepare the Plant for Extraction
Lightly water the plant, let it dry for an hour or so, and then gently remove the plant from the pot. You can do this by turning the pot over and gently pulling the pot up and away from the root ball. It is not a good idea to yank a plant out of its pot by the stem.
Care for the Root Ball
It is okay to gently loosen the root ball with a finger or a fork, but be careful not to cause any root damage. Cut away dead or rotted roots. If you plan on repotting the plant into the same size pot, you may want to root prune your plant.
Prepare the New Pot
In general, you should only repot a plant one size up. You can move from a four-inch to a six-inch pot, but not a four-inch to an eight-inch pot. Moving up in size too quickly can slow growth. Plastic or ceramic pots are fine, depending on your preference. Add fresh potting soil directly to the pot. You do not need to add pebbles or other drainage media to the bottom of the pot. This reduces the growing area for the roots and hastens the decline of the potting soil by paradoxically reducing aeration.
Gently set the new plant in its new pot and backfill with soil or compost. One of the main causes of plant collapse is planting too deep. Make sure the newly potted plant is not planted deeper than it was in the original pot. As you are filling in, press the soil down firmly and tap the pot gently to settle all the dirt.
Water thoroughly, and if necessary, add a little more soil to top it off. You should water until liquid seeps from the drainage holes at the bottom of the pot.
When to Fertilize
When it comes to fertilizing newly repotted plants, most store-bought compost or soil mixes have fertilizer included. In general, you should not fertilize newly repotted plants for six weeks. If you are conservative about fertilizer when you first repot your plant, it will reduce the chances of burning the new root growth.