All gardeners know the value of a raised garden bed for their yards, but choosing the right material for your garden bed out of the surplus of choices can be the difference in a fruitful yield for aspiring gardeners. Wood, metal, plastic, and cement are commonly used materials for building a raised garden bed. Choosing the right material can significantly impact the durability of your garden bed which will determine how long your garden bed will last over the years. This article is written to help you decide on the best material for raised beds for your garden. In this blog, we honed in on metal garden beds – creating a pros and cons list to give you a brief overview of the most important features of metal.
Pros of Metal Raised Garden Beds
- Durability: Metal beds are known for longevity and can withstand weather conditions for long periods. If properly cared for, metal beds can last around 25 to 30 years, outlasting wooden or plastic beds by a landslide.
- Pest Control: Raised metal garden beds can protect plants from pests, such as slugs and snails because their smooth, slippery walls make it harder for them to climb.
- Heat Retention: Metal can absorb and retain heat, extending the growing season in colder climates. However, this can be a drawback for hotter climates. Continue reading below for more detailed information.
- Aesthetics: Many gardeners are attracted to the modern look of raised metal garden beds, which can give your urban garden an edgy, trendy feel.
Cons of Metal Raised Garden Beds
- Blocked Air Flow: Metal beds are not as breathable as organic materials such as wood or woodcrete composite, meaning oxygen can’t reach the soil. Additionally, metal beds make it easier to overwater plants because water tends to collect at the bottom of the planter instead of soaking into the ground. This can lead to root rot, as plants may sit in standing water at the bottom of the bed. Metal bed owners should be cautious of this risk.
- Price: Some metal raised garden beds can be pricey, depending on the look and where you source the materials.
- Rust: Metal can rust over time, especially when exposed to soil with higher acidity.
- Zinc: Some types of steel, such as galvanized steel, are often treated with zinc to inhibit corrosion and rusting. In turn, the zinc can leach out of the metal into the soil and be taken up by plants. Remember that a small amount of zinc is safe for consumption, as it is a natural mineral in soil, but too much zinc can be toxic for people.
- Heat Retention: Certain types of galvanized metal retain heat a bit too well, which can make the soil too warm for more sensitive plants.
- Safety: Some, but not all, metal beds have sharp corners, which can be a hazard if someone takes a fall. Especially with younger children running around the garden, these sharp corners pose a threat to the safety of those around the garden beds.
Metal Beds vs. Durable GreenBeds
- Durability and Longevity: Durable Greenbeds rank about as high in durability as metal, with both estimated to last about 25 years or more. Both materials are known for their exceptionally high durability, compared to other options like wood or plastic.
- Pest Prevention: Metal helps prevent slugs, but Durable Greenbed’s construction has reportedly eliminated pest problems, according to the reviews of many gardeners.
- Soil Health: Durable Greenbed’s non-toxic and environmentally friendly materials are designed to give you the same breathability as wood garden beds but with improved longevity. This will keep air and water flowing and keep your soil healthy. The same cannot always be said about metal, which might trap air or water flow.
- Affordability: The price is dependent on where you buy garden beds, but in general, Durable Greenbeds and metal garden beds have similar costs due to their high tolerance against weathering.
- Customization: Durable Greenbeds can be tailored to fit any garden space, and upon request, can be adjusted to the unique needs of any gardener, which is not the case with metal garden beds.
How to Maintain Metal Raised Beds
While the typical lifespan of metal raised beds is estimated to be upwards of 20 to 30 years, proper maintenance is a key factor in the predicted longevity of your garden beds. Metal also has certain properties that can make growing food in metal beds toxic for consumption. Here are some tips for making your metal garden bed last as long as possible as well as growing food that is safe to eat.
- Since many gardeners use galvanized steel for its high durability, we often hear the question: Is galvanized metal safe for raised garden beds? The answer is, generally, yes, however, it is possible for a small amount of zinc to seep into your soil over time with exposure to water, especially if your soil has a higher acidity, as it can cause steel to break down more quickly. To prevent zinc from leaching into the soil, avoid soil with high acidity.
- You will also want to avoid acidic soil to prevent your metal garden bed from rusting. Generally, most gardeners use soil that is closer to a neutral pH , so this won’t be a problem, but if your plants require soil that is higher on the acidity level, say anything less than 6 or 7 on the pH scale, you might want to consider a material other than metal.
- If you live in a climate filled with endlessly sunny days with intense heat, you may need to water your plants more frequently if they are in metal beds than if they were in another type of garden bed. Check on your garden soil often throughout the day to see if it looks dry, and ensure your watering methods keep the soil moist.
What is the best material for raised beds?
Metal garden beds are a great option for gardeners who are looking for garden beds that will last. They have incredibly high durability but require a certain amount of maintenance to stand up to the years of weathering. However, keep in mind that they might block air and water flow in your soil and that acidic soil can corrode and oxidize metal, which can become a hazard for food consumption. In contrast, Durable GreenBed’s raised garden bed kits are better for the health of your soil due to their breathability, and require little to no maintenance. We encourage you to weigh the pros and cons carefully, considering your preferences, climate, and needs, before deciding on what material is best for your garden. For more information on and for further comparison of Durable GreenBed and other types of garden bed materials, visit the frequently asked questions about our garden kits.