What is the Difference Between Potting Mix & Potting Soil?
If you’re new to the world of gardening, you might be worried about seeing terminology that could be confusing – especially when you want to ensure your plants are potted in the best possible environment for their needs. If potting mix vs. potting soil is high on your list of concerns, Patio Growers is here to help with a comprehensive overview of the two potting mediums.
As you start your windowsill or balcony garden, let us help guide you along the path to beautiful greenery and stunning blooms! Check out our guide below to learn about the main differences between potting mix and potting soil today!
Defining Potting Mix vs. Potting Soil
First and foremost, potting mix is a gardening medium that doesn’t actually have any soil. This material is composed of organic matter with small micro-organisms that provide your plants with a sterile environment. With potting mix, you’re guaranteed a medium that’s completely free of pests, fungus, and other contaminants. It’s also designed to maximize plant growth and can contain anything from peat moss and perlite to pine bark and compostable organic matter.
On the other hand, potting soil is mainly made of dirt. It can be completely composed of dirt or a blend of soil and potting mix. Most gardeners will use potting soil to fill in low spots in big pots or the borders around raised plant beds.
While their composition is one important difference between potting mix and potting soil, it’s not the only one. We’ll also need to review many other characteristics of these mediums before you can make a well-informed decision about what’s best for your garden.
1. Affordability of Potting Mix vs. Potting Soil
The reason many gardeners prefer potting soil is that it’s a bit more affordable than other planting mediums. It’s also usually readily available in your yard! You can mix whatever soil you already have in your garden with compost, manure, and other nutrient-rich materials.
When you buy potting mix, you can expect the price difference to be pretty apparent. For some who don’t have fertilizers on-hand at home, the mix is a worthy buy for convenience and expert nutritional blends that target specific plant varieties, like succulents, flowers, or vegetables.
2. Fluffiness of Potting Mix vs. Potting Soil
When you pot your plants, you want the soil to have a sense of fluffiness to ensure the roots have enough space to propagate. Fluffy soil is also loose enough to allow more airflow. Unfortunately, potting soil easily compacts, losing its fluffiness pretty quickly. Most gardeners prefer a blend of soil and mix to provide a better medium for root growth and aeration.
3. Aeration & Drainage of Potting Mix vs. Potting Soil
If you choose to work with potting soil, you’ll need to be mindful of the drainage and aeration of this medium. You can puncture small holes in the soil to keep it loose and allow air, water, and nutrients to penetrate the roots. Over time, your potting soil will become more compacted inside containers, which means you’ll need to repot your balcony herbs and plants a bit more frequently to ensure no interruption in the flow and drainage of water.
Using potting mixes for container gardens has a clear advantage and allows your plant roots to enjoy excellent drainage and airflow.
4. Nutrient Differences in Potting Mix vs. Potting Soil
While dirt does have some natural organic matter and minerals that offer stable nutrition to your plants, store-bought products are more reliable than what’s currently in your garden. You can shop for fully organic and eco-friendly potting soil to make better choices for your plants and the environment.
With potting mixes, it’s a guarantee that you’re getting many more nutrients per pot than with soil. The downside here is that most mixes aren’t all-natural because they strive to combine the optimal materials to provide plants with proper nutrition.
5. Potting Mix vs. Potting Soil for Container Gardening
If you don’t have a ton of space in your backyard, container gardening with automated watering is a great solution. You can use any type and size of container to grow your plants in a way that’s convenient and aesthetically pleasing. However, with container gardens, we believe that straight potting soil is not the ideal choice!
In an open environment, potting soil can deliver what your plants need, but letting it compact in a pot will result in blocked circulation and waterlogged roots. We also don’t recommend it when starting plants from seed because the tough, heavy particles make it difficult for the seeds to germinate. Potting mixes are the ideal choice here. Even if you use some blend of soil and mix, your garden will see better growth and more blooms.
6. Lifespan of Potting Mix vs. Potting Soil
Potting soil will pretty much last forever as long as you occasionally add some sort of fertilizer to keep the nutrient level high. You may also need to repot and turn over the soil occasionally to prevent that root constriction we previously discussed.
Potting mixes, however, will definitely break down as time passes, which makes the entire blend useless. If you don’t use stored mixes before their expiration date, they won’t provide any benefits to your plants. You also cannot revive potting mixes with added fertilizer.
Making Your Choice
Now that you know the main differences between potting mix and potting soil, you’re better informed about the options you have for your garden. Regardless of your garden size or style, we recommend having both mix and soil on hand to blend and use as needed, depending on each plant’s preference. Just keep an eye out for contamination in your soil and expiration in your mix!
If you have more questions about potting mix vs. potting soil, automated watering systems, or other garden questions, we’re always here to help. Explore our growing guides to find advice for specific plants, as well as our blog for more general gardening articles!