Can You Reuse Potting Soil? Absolutely! But Here's What You Should Know
Potting Soil Deep Dive
At Worm Farm Portland, we know that great soil is the foundation of a thriving garden. Whether you're planting juicy tomatoes in raised beds, cheerful flowers in pots, or leafy greens in your in-ground plot, the right soil makes all the difference. A common question we get this time of year is: Can I reuse my old potting soil? The answer is yes—with some care and a few smart steps.
That said, if you're building out new raised beds, prepping flowerpots, or starting an in-ground vegetable garden, it's often worth investing in fresh, rich organic soil blends that are specifically tailored to your plants' needs. Here’s you’re our suggestion and complete guide to reusing old potting soil—knowing when it’s time to treat your garden to something new.
Why does “my” Potting Soil Breaks Down?
Potting soil starts out full of life—fluffy, dark, and full of organic materials like compost, cococoir, worm castings and pumice. But after a season or two, all that good stuff begins to break down. The nutrients deplete, the pH shifts, and the structure can become dense and lifeless.
You might see:
Yellowing leaves
Stunted growth
Droopy plants
Pest issues
Compacted, pale soil
That’s your cue that the soil needs either a revival or a fresh start.
How to Revive Used the Worm Farm Potting Soil
1. Clean it up
Start by removing roots, old plant debris, and any visible pests. You want a clean base to work with.
2. Sterilize the soil
Kill off harmful pathogens or lingering bugs by:
Solarization: Spread soil on a tarp, cover with clear plastic, and let the sun do the work.
Oven: Moisten soil, spread on a tray, and bake at 180–200°F for 30 minutes.
Microwave: Heat moist soil in a microwave-safe container for 4–7 minutes.
3. Add nutrients back in
Mix in high-quality compost, worm castings, or blend with ideally with new potting soil. Better yet, combine it with one of our fresh, organic mixes below to give it a nutrient boost and new life.
Best Organic Soil Mixes for Your Garden Goals
Looking for the ideal soil solution? We’ve got you covered:
For Raised Beds with Vegetables
Go with our premium blends:
Gwen’s Mix – A rich, well-balanced organic soil perfect for all veggies.
Happy Half Gwen’s Kelp Myco Mix – Gwen’s Mix plus organic kelp and mycorrhizae for enhanced root health and nutrient uptake.
Both are fully organic, OMRI-listed ingredients, and designed to help your raised bed garden flourish with vigor and yield.
For In-Ground Gardening
The soil in the ground often needs loosening and revitalizing. That’s where our:
Organic Wildwood Conditioner comes in. It’s made to amend native soils, improve structure, increase organic matter, and bring life back to tired earth. Use it in a ration 1:1 (and don’t stretch it to thin)
Ideal for vegetables, fruits, and herbs planted directly into the soil.
For Flower Gardens & Containers
Colorful blooms deserve nutrient-rich, biologically active soil. We recommend:
Organic Kelp Myco Mix – Crafted to feed flowers all season long. Kelp adds trace minerals and promotes flowering; mycorrhizae build a robust root network.
Perfect for flower beds, hanging baskets, and decorative pots.
Extra Uses for Old Potting Soil
If you’ve already got some used soil, don’t just toss it! After refreshing it:
Use it as a few inches of a base fill in raised beds.
Mix it into borders or berms.
Add it to your compost pile to increase volume and texture.
Storing Refreshed Soil
To keep revived soil in top condition, store it in a sealed plastic bin or airtight bag in a cool, dry spot. This prevents excess moisture, pests, and decomposition from setting in before you're ready to use it again.
FAQs – Soil Know-How from Worm Farm Portland
How do I know it’s time to replace my potting soil?
If your soil is compacted, light-colored, smelly, or causing poor plant growth, it’s time to refresh or replace. Plants will give you a lot during a season, so give them some nice food and they will provide!
Can I use reused soil for all plant types?
Yes—with the right amendments. But for best results, pair soil to plant type. We’re happy to help!
Why is sterilizing soil important?
It prevents pests and diseases from being passed on to your next planting round.
How can I improve drainage in tired soil?
Add compost, pumice, or even a bit of our Gwen’s Mix to restore a light, well-draining texture.
Invest in Your Garden’s Success
Reusing soil is a great way to save resources, but when you're aiming for peak performance in your garden, nothing beats the results of fresh, living soil made for your exact planting situation.
Let Worm Farm Portland set you up with:
Premium raised bed mixes for veggies
In-ground conditioners for edible gardens
Specialty flower blends for beautiful blooms
One yard of our Premium Gwen’s Mix ($165.00) will feed your garden all season long—and costs about the same as one nice dinner out for two. But this meal keeps on giving, with veggies on your plate week after week!
Stop by or contact us—we’re happy to help you build healthy soil and a thriving garden you’ll enjoy all season long!