Should You Toss Your Old Potting Soil?
November 30, 2025 | By TigreBlume
When I first dipped my toes into gardening🥬, I treated my container or planter soil like a single-use product. Following the common wisdom I found in gardening publications and on tv programs, I assumed that once the season was over, the potting mix was "spent"—totally depleted of the essential nutrients plants need to thrive. As soon as the growing season ended, the spent soil from every planter went straight into the trash (or the deepest corner of the yard). I dutifully bought bag after bag of brand-new potting mix every year to refill every planter. I did this faithfully for many years until I ran across a few content creators on YouTube who swore by simply amending the old soil with beneficials and nutrients...and their flowers and vegetables were flourishing. So...I thought I would give it a try and see if I got the same results.
It took me some time to figure out how best to amend the old soil and let me tell you there was a lot of trial and error! At first, I tried just adding granulated fertilizer to the old soil. That helped, but I found my soil was still lacking the necessary nutrients my plants needed to put out bright green foliage and nice sized flowers and fruit. I played around with a few different techniques until I found success. It turns out, you don't have to throw away that potting soil—you just have to recharge it😊.
Fast forward to today, and I still believe in reusing old potting soil. Not only is it good for the environment, but it is also a good way to save money or invest those dollars elsewhere in the garden. There are obviously going to be instances where it is best to start with fresh store bought soil, such as if you are dealing with wide-spread plant disease or pest infestation. However, more often than not, this isn't something you will experience each season - so why not save some money and use what you have as a starting point.
The process of bringing "dead" potting soil back to life is surprisingly simple. First, you need to sift through the old soil to remove any stubborn roots, debris, or pest eggs—just give it a good shake through a garden sieve or sift through it with a small garden cultivator. Once you have a clean base, the goal is to replenish the soil structure and add back the missing nutrients. You can do this by blending the old soil with a few key amendments: adding fresh compost (the ultimate soil food!) restores organic matter, a handful of slow-release fertilizer provides essential nutrients for the next round of planting, and a scoop of perlite or vermiculite ensures the mix stays light and well-draining. With just a little elbow grease and a few inexpensive additions, you can transform that tired, spent dirt into a nutrient-rich foundation ready to support a vibrant new season.
I am having great success with this method of reusing the soil in my planters and raised garden beds!
Here is how I re-use and repurpose my old soil👩🌾:
Patio/deck planters - This category consists of movable planters that I use to grow flowers and vegetables out on my patio and deck. I empty out the old dirt into a big storage container (removing large root balls and debris) and use as a basis for a nice composted soil for the next season. Once I fill the storage container with all of the old dirt from my patio/deck planters, I add old plant foliage (only those free of disease and pests), food scraps (banana peels, egg shells, potato skins, etc.), leaf mulch, used coffee grinds, and worm castings. I turn it a few times before we get a really hard frost and everything usually breaks down by the time I am ready to start planting out again in the late spring. I use it to fill up all of my containers and amend with perlite and granulated fertilizer, and in some cases bone meal and/or blood meal (only for those I plan to use to grow vegetables). If I have some leftover composted soil after I fill up all the contains, I will also use it as a topper (e.g., add it to the base of my plants) in the late spring or early summer. If I don't have enough to fill up all of my containers, then I will purchase more from the store to supplement what I have.
Greenstalk planter - I have a seven tier leaf planter and each tier houses a lot of potting soil. I don't remove the dirt at the end of the season. I leave it in place over the winter and amend with granulated fertilizer, worm castings, bone meal (high in phosphorus and nitrogen) and blood meal (high in nitrogen) in the spring. I mostly grow vegetables in my Greenstalk planter, so it is important that I add plenty of nitrogen and phosphorus back into the soil prior to planting. I also add a liquid fertilizer every 2 weeks.
Raised garden beds and fabric pots - I also don't remove the dirt here...I add old plant foliage (only those free of disease and pests), food scraps (banana peels, egg shells, potato skins, etc.), leaf mulch, and used coffee grinds before I put them to rest for the winter. Then, in the spring, I will amend with perlite, worm castings, blood meal and granulated fertilizer. I also top with store bought compost, and add a liquid fertilizer every 2 weeks (fish emulsion for the first 3-4 feedings, and then a balanced liquid fertilizer the rest of the season).
Before you grab that shovel and toss out all your container soil this year, remember the three major wins of reusing and recharging: less waste, lower cost, and healthier soil structure.
Give the process of amending your old soil a try during your next growing season. If you're not comfortable going all in with this method, start small and try it on one or two containers. Depending on the outcome, continue to apply this technique to more spaces in your garden or tweak your method as necessary to get your desired outcome. Not only will your wallet thank you for buying fewer bags of new potting mix, but you'll also be fostering a more sustainable, vibrant, and rewarding growing environment right in your own pots.
Happy planting💖!
