Night yields to day in the late winter and spring, which seems to reenergize me. Already I've found time to get in the yard to do a bit of cleaning. Near the house, daffodils push their way through the leaf mulch beginning their march skyward, racing to beat the shade thrown by the trees. Magnolia buds in the neighbors yard are swollen, ready to burst in an explosion of flowers. The grass has switched from khaki-colored to green in a matter of a few days. This is a good change.
Even if the change is good, it is not always easy. Repotting a houseplant can be quite stressful for the plant. The gardener knows for plants to thrive, it must leave the comforts of the nursery or greenhouse and extend its roots into new and larger volumes of soil. This thought still doesn't make the change easy. Even the gardener may panic at tearing apart pot-bound roots or when the plant exhibits transplant shock. Trees may drop many of their leaves; houseplants may wilt and die back a bit. Often give the plants enough time, adequate water, the right light and they will establish a good root system and perk back up.
But not every plant can tolerate transplanting as easily as others. Here are some tips to reduce transplant shock to your houseplants.
- If you see roots growing out of the bottom drainage holes of the container, it is time to repot the plant. Don't see any drainage holes? Then it is also time to repot into a container that has drainage holes. As you may have guessed, good drainage is essential.
- Choose a new container that is two inches larger in diameter than the original. Selecting a pot with an excessively large soil volume can lead to root rot because the plant can't use the available water.
- If you are reusing a pot, clean it thoroughly with a scouring brush and dip in a 10 percent bleach solution to kill any disease-causing organisms. Rinse with clean water.
- Plant most houseplants in a soil-free potting mix. The soil-free potting mix is very light. Often I find "potting soil" on the garden center shelf in an incredibly heavy bag when compared to soil-free mix. Don't use the heavy "potting soil."
- Make sure the plant is hydrated by watering an hour before repotting. After watering is a good time to remove any dead or unsightly foliage.
- Place a coffee filter or paper towel in the bottom of the pot, which will allow water to drain out the bottom, while keeping the potting mix from draining out too. Don't put a layer of gravel or grit in the bottom of the pot. Contrary to popular belief, a layer of gravel in the bottom of a pot does not facilitate better drainage. It actually can do the opposite.
- When repotting, break up any pot-bound or circling roots, so you no longer have a dense mat of roots on the outside of the root ball. I tear off chunks of roots and the top edges of the root ball.
- Place the plant in the pot at the same height it was in the original container. Fill in with soil around the edges and firm up the potting mix to give good contact with the roots and so there isn't much settling.
- Leave a one-inch gap between the top of the potting mix and the top of the container for watering and plant growth.
Water the plant and place in its intended location. If indoors, allow water to drain into a saucer under the pot and then dump any excess water still present after 20 minutes. If placing plants outside, I typically will not use saucers under my containers unless I want to protect the surface where the container resides.