Why It Looks Like Your Houseplant Is Losing Soil & What To Do About It

Are you looking at your houseplants that have been in the same pot for quite a while and noticing that some of the potting soil seems to have disappeared? If so, you might be wondering how this can happen. Don't worry, you're not doing anything wrong and your plants are not consuming the soil. It's just a common phenomenon known as soil compaction and will happen to all your potted plants over time. This could also be one of the reasons that your houseplant isn't absorbing water the way that it should.

One of the reasons that soil compaction occurs is because the soil is confined to a pot and the roots have a limited space to grow which means they're restricted in their ability to work through the potting mix to loosen it up. Plus, there are generally no critters like earthworms in pot plants to help separate the soil particles and open up the water and air pores within the mix. Finally, many potting soil mixes contain organic materials such as pine bark, peat, or coco coir that will eventually break down, resulting in further compression due to a lack of larger particles. While soil compaction can be detrimental to your houseplants because it reduces effective drainage and limits the amount of air space in the mix, there's an easy fix that will give your indoor plants a new lease on life.

While it might be tempting to just top off the mix in your pots, this is not really going to solve the problem of the soil compaction down at the root level. Instead, you could help loosen up the compacted soil a little by very carefully poking a chopstick or skewer into the mix in a few places. Be gentle so you don't damage the roots of the plant. This is similar to aerating the soil in your lawn.

A far better solution is to repot the plant into a new mix. Ideally, you want to change your plant's soil every one to two years but some can be done every three to four years. Try to choose a good quality potting soil that contains organic materials. You can even break up the mix further by adding some perlite or vermiculite which will create larger air and water spaces. 

To refresh your houseplant's potting soil, remove the plant from the pot and gently loosen as much of the old soil from around the roots as possible. Take care when you're doing this so you don't damage any of the roots. You also want to note that some houseplants, such as hoyas, African violets, and aloes, don't like having their roots disturbed, so these need to be repotted with care and it's best not to tease out the soil around the roots. Finally, don't forget that you can reuse old potting soil by freshening it up with some added ingredients.