Alright, folks, let’s talk about dirt. Specifically, can you use that bag of indoor potting soil you’ve got lying around for your outdoor plants? I’ve been wondering about this for a while, so I decided to get my hands dirty and find out.
First, I grabbed that old bag of indoor potting mix from under my sink. You know, the one that’s been sitting there since I repotted my snake plant last year. It felt pretty light and fluffy, which is great for indoor plants that need good drainage, but I wasn’t sure how it would hold up outside.

Then, I went out to my garden and dug up a little patch of soil. It was way denser and heavier than the potting mix, with some clay and rocks mixed in. This is pretty typical for outdoor soil. It holds onto water a bit longer, which is important for plants that are out in the sun all day.
Next, I decided to do a little experiment. I planted a few marigold seedlings in separate pots. Some got the indoor potting mix, some got the outdoor garden soil, and a couple got a mix of both. I watered them all the same and put them in a sunny spot on my patio.
Here’s what I found after a couple of weeks:
- The marigolds in the pure indoor potting mix did okay, but they dried out really fast. I had to water them almost every day. They also seemed a little less sturdy than the others.
- The ones in the garden soil did pretty well. They held onto water better and seemed to be growing a bit faster.
- The marigolds in the mixed soil did the best! They got the drainage benefits of the potting mix and the water retention of the garden soil.
So, what’s the conclusion? Well, you technically can use indoor potting soil for outdoor plants, but it’s not ideal. It dries out too quickly and might not provide enough support for bigger plants. If you’re in a pinch, you can mix it with some regular garden soil to make it more suitable for outdoor use. Otherwise, it’s best to stick with garden soil for your outdoor plants and save the potting mix for your indoor buddies.
This whole thing reminded me of the time I tried to use regular printer paper for watercolor painting. It just didn’t work! The paper got all soggy and the colors bled everywhere. It’s like, you gotta use the right tools for the job, right? Same goes for soil!
Anyways, I hope this little experiment helps you out. Happy gardening!