“Can I use garden soil in containers?” This is a common question and it makes sense that using garden soil in pots, planters and containers should work. Unfortunately, there are many good reasons not to use this money-saving approach. Here’s why:
Can You Use Garden Soil for Containers
For the most part, garden soil can be the ideal medium for growing plants in the ground. The native soil in your backyard has a natural ability to drain off excessive amounts of rainwater, yet it can also retain moisture during dry spells. It’s full of beneficial insects, fungal colonies and even burrowing rodents to aerate and break down organic matter.
All these things work well together to provide in-ground plants with the things they need to grow and flourish. Yet using garden or topsoil in containers often has the opposite effect. Potted plants grown in garden soil typically languish. The main reason this happens is because garden soil is much more dense than media formulated for containers.
Try this little experiment: Fill up a medium to large container with a commercial potting mix and an identical container with an equal volume of garden soil. Notice how the one with garden soil is heavier? This is because garden soil is much denser than bagged potting soil. Dense soil is not only heavier, it has these qualities that make it undesirable when using garden soil in containers:
- Compaction – The creepy crawlies that keep our garden soil loose aren’t generally welcome in our potted plants. Without them, dense soil easily becomes too compact for ideal root growth.
- Poor drainage – Dense soil also slows down water flow. Using garden soil in pots can make it difficult to maintain the proper soil moisture levels, which can lead to root rot.
- Lower oxygen availability – Root cells need oxygen to survive. Using garden soil in containers reduces the air pockets which make oxygen available to the plant’s roots.
In addition to these issues, using native topsoil in containers can introduce harmful pests, diseases and weeds to your potted plants. Native soil can also lack necessary nutrients or have less than ideal pH levels for the type of container plants you wish to grow. Amending small amounts of soil is more difficult, as exact measurements are required to balance nutrient and pH levels.
Alternatives to Using Garden Soil in Pots
Purchasing bagged potting soil is the easiest alternative to using garden soil in containers. While the initial outlay can be more expensive, the extra labor and cost of replacing plants can outweigh the purchase price of bagged soil in the long run. Additionally, premium potting soil can be reused providing you had no disease or pest issues.
Another alternative to using topsoil in containers is to make your potting soil. These mixes can be custom blended for seed starting, cacti and succulents, orchids or any type of plant you wish to grow. Here are a few ingredients that can be used when custom blending your own potting soil:
- Coconut coir
- Organic compost
- Peat moss
The growing medium you choose is the lifeblood of any container plant. If you opt for the best you can afford, you’ll give your plants the best chance for success.