Repotting Indoor Plants Correctly

One of the most frequent questions asked when buying a plant is about repotting. In most cases plants do not need repotting. Reputable nurserymen would not think of selling a pot-bound plant, because if the plant were put into a bigger pot and kept for a couple of weeks, it could grow better and fetch a better price.

Compost

When your plant does eventually need repotting, you will not find it difficult. It is easy to pick up a few simple tricks from the trade. The first essential is to identify in which type of compost the plant to be repotted has been grown. It is important to use the same type of compost. Never repot too soon; if in doubt, leave it for a few more weeks.

Removing plants from pots

The easiest way to tell when a plant is ready to be moved is by its roots. Remove the plant from its pot, by upending the plant, placing one hand across the top of the soil and at the same time gently gripping the stem or leaves. Then tap the top rim of the pot against the edge of a table or bench, holding the pot in the other hand. The pot should slide off the plant. Sometimes it is necessary to tap in several places.

At all times handle the plant gently, supporting the stem and foliage with your hands, and remembering you are dealing with a living object. Never bang the pot hard to remove the plant, as you may damage the root system.

Pot-bound plants

The plant that needs repotting has a mass of roots all closely bound together with no soil showing underneath at all: this is called pot-bound. If any soil is showing, do not repot. Other signs can sometimes be seen in the growth. If the leaves go very small and the plant is slow in growing, it may need repotting, although this problem can more often be solved by feeding.

Remember, especially with flowering plants, you get a better show of flowers if the plant is pot-bound, especially if it is well fed. The plant puts all its energies into producing flowers instead of new roots.

Don’t repot just because a plant looks top-heavy or unsightly in a small pot. The problem can often be overcome by placing the whole pot into a bigger one and packing the intervening space with wet peat or moss. This will help with humidity around the plant, as well as improving its appearance.

How to repot

The first step in repotting is to make sure that the plant is well watered. This binds the compost together and helps the plant to withstand the shock to its root system. Remove the pot. Put the old pot aside to be washed and stored for future use. Now examine the root carefully, looking for any damaged roots or any dead root material. This should all be removed with sharp scissors or secateurs. Gently break apart the roots at the bottom of the ball and carefully remove any crocks or other material used for drain-age, again cutting away damaged roots. Now look at the top of the root ball and remove all the compost around it.

Choosing the new pot and planting

The new pot should not be more than two sizes bigger than the old one. Make sure it is clean and dry. Put a layer of crocks or other drainage material on the bottom and cover this with a piece of newspaper to stop the compost blocking the drainage material. Add some compost and lower the plant on to it in the center of the pot. Supporting the plant with one hand, add a stake if necessary and put in fresh compost up to 1-2 cm (H in) from the top.

Large plants

These require different treatment if they are too unwieldy to uproot. If you damage the roots you can harm the whole plant, and it is better to rely on feeding than changing the soil.

A good alternative is top dressing. With a trowel remove as much of the old soil as possible without disturbing the roots. Look for pests and worms, which should be removed.

As with repotting, it is best to perform this operation when the plant is growing. Put in new dressing to replace the old and firm down. To allow the roots time to get used to the new medium, do not water or feed immediately after repotting or top dressing.