Repotting Your House Plants

Sharon Lance
Adams County Master Gardner

There is never a wrong time to repot your houseplants, but this time of year we have more time in the house to evaluate our plants needs, if any. Some plants need to be repotted every year at a specific time, often in the spring as they begin a new growth period. Some signs that your plants needs to be repotted are stunted foliage, smaller leaf growth, plants wilting between watering, lower leaves are yellow, roots appear at the soils surface or grow thru the drainage holes.

Repotting your plants is a relatively easy task. You will need new or clean used pots, sterilized soil medium and gravel or small pebbles and a new or used sterilized container.

Flower Pots: Clay and unglazed ceramic pots allow the plant's roots to breath, but also loose their moisture more quickly than plastic pots, which are not porous. For plants that need to dry out between watering, like cactus and other succulents, a clay pot would be a better choice. If you elect to use a clay pot make sure that the pot has been conditioned by immersing it in water for several hours before use. Clay pots that haven't been conditioned draw water from soil and rob the plant of its moisture. Used clay pots should be washed to remove soluble salts and sterilized by immersing in a solution of 1 part liquid bleach to 9 parts water. Rinse well. Also, clay and grazed pots are heavier and work better when planting large or taller plants.

Plastic and glazed ceramic pots hold moisture longer and are preferred for plants that need a lot of water and like even moisture, such as miniature roses. They should have a drainage hole or a layer of rock or pebbles in the bottom of the pot to hold the extra water that is unable to drain. Plastic pots are easy to sterilize and tend to accumulate fewer salts.

The flowerpot you select should be large enough to provide room for soil, the root ball, have sufficient headroom for proper watering and provide bottom drainage. Also the pot you selected for repotting should not be more than 2 inches larger in diameter than the pot it is growing in. If the flowerpot is too large in relation to the plant, the soil will dry out slowly and it will be difficult to control the moisture. The top of the soil may be dry to the touch while the soil in the center of the pot may still be wet. Also, for drainage holes in your container that are large you can use wire mesh, pieces of broken chard, stones, a coffee filter or even a bottle cap can be used to limit the loss of soil/nutrients from excess water drainage.

Potting Medium: Besides anchoring the plant, potting soil serves many purposes. It acts as a reservoir for nutrients and if the structure is correct will achieve balance between moisture, air be and a host to beneficial micro-organisms. Many of the commercial mixes contain no soil but slow-release fertilizers such as perlite, which is a sterile material produced from heating volcanic rock, vermiculite, which is a sterile, lightweight mica product, and sphagnum peat moss which is partially degraded vegetable matter found in marshy areas. A good potting mix or soil should be porous for root aeration and drainage but also be able to retain moisture and nutrients. There are many high-quality potting mixes on the market and many of the new soil less mixes come with water soluble materials in the mixes. Another option is to mix your own potting soil using 2 part garden loam; 1 part leaf mold or peat moss and one part sand, perlite or vermiculite.

To report your plant start by supporting you plant with one hand while tapping it out of the pot or you may need to invert the pot and tap the rim on a hard surface. One suggestion before you repot your plant is to water your plant the day before or several hours before you repot your plant so that all of the soil ball will be uniformly moistened and easier to remove from the existing pot. Next, position the root ball so that it is at the same level it was previously growing; adjust the soil mix as needed to fill in the sides of the pot. Firm the potting soil with your fingers making sure that you allow a to 1" opening between the top of the soil and the rim of the pot to allow space for watering. When the pot is full thump down on solid surface to firm down the soil. It is important to firm the soil around the root ball because new soil is always lighter and airier than the soil ball in which the plant has been growing. If the new soil hasn't been firmed down, any water added to the plant will quickly wash away through the new soil and the roots may not be sufficiently moistened. Water plant thoroughly but never let water sit in a container after it drains. The plant should be set in a location with sufficient light, but not sunny, for a couple of days until the plant has had time to adjust to being repotted. During the next couple of weeks the plant will develop feeder roots and root hair roots a process that requires air and water in the soil. So be careful not to over water the plant.

When you are ready to repot your plants take a close look for signs to see if your houseplant needs to be repotted. Determine the size of the container, keeping in mind the general rule is to select a pot that is 1 to 2 inches larger than the pot the plant is currently growing in. Purchase a good quality soil mix or you can make your own. After you have repotted you plant(s) make sure the soil has been firmed down, sufficiently watered, and place in indirect sun light for a couple of days to adjust to being repotted. Enjoy.

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