The 8 Best Raised Garden Bed Materials Recommended
When it comes to building raised garden beds, the possibilities are many.

Loft beds can come in countless shapes, sizes, layouts and materials. From wood, metal, stone, and plastic to wine bottles, dressers, animal troughs, canoes, and cardboard boxes, there's no shortage of creative ways to create your above-ground garden dreams.

Generally, the more expensive the material used to build a loft bed, the more durable and long-lasting it will be. Still, you can find high-quality materials at surprisingly low cost by upcycling, recycling, and cleaning your building supplies.

Whether you're refurbishing the material or just buying it from the store, not all loft bed materials are up to the task.

8 Best Raised Bed Materials

A good raised bed material should be durable, easy to use, and safe to use around people, plants, and soil. If the eyes are comfortable too, that won't hurt either.

Other things to consider before using raised bed materials include cost, availability in your area, how the material will perform in your particular climate, and whether you prefer a permanent structure or one that can be moved.

wood

The traditional material of construction for a raised bed is wood, and for good reason. The timber forms an attractive raised bed that blends perfectly with the natural garden setting.

It's also probably the most versatile - the wood can be cut to size easily and only the most basic building skills are needed to throw it together.

There are endless design options when working with wood. Wooden loft beds can be made in any size, height and shape to suit your garden landscape. Build the classic 6'x4' rectangular planter. Or build loft beds and keyhole beds for added convenience. The cascading tiered frame and corner bed create a beautiful focal point and keep things visually interesting.

untreated wood

Milled wood boards are strong and durable, and usually last for years before they start to deteriorate. But they eventually rot.

Use naturally rot-resistant woods like cedar and cypress and seal them before building for the most durable wooden raised beds.

logs

Logs, twigs, and sticks are very rustic alternatives to planks, and you can often find them for almost free.

Locally harvested logs are also one of the most environmentally friendly ways to obtain timber building supplies.

Wooden logs and branches can be stacked to form a frame or arranged vertically around the perimeter. Another option is to weave long, flexible branches into a hedge to anchor the garden's soil.

Masonry

Masonry, such as natural stone and brick, is an excellent raised bed material that lasts almost forever.

Ideal for both informal and formal garden settings, masonry will create a strong and durable framework that requires little maintenance. These materials can assume a variety of shapes and forms, making them particularly suitable for curved and contoured walls that wrap around winding paths.

In temperate climates, masonry raised beds help extend the growing season. As a radiator, the stone sculpture absorbs the sun's heat during the day and releases the accumulated heat into the soil at night.

That said, masonry can be very expensive when you need a lot of it. It is heavy and difficult to use.

If you want to build deep and raised beds, you may need to use mortar or cement to hold them together, making the frame a permanent part of the hardscape.

Natural Stone

Granite, sandstone, limestone, rough stone, slate, slate, basalt and pebbles are just some of the natural stone options.

These stones were formed millions of years ago, and their composition and appearance depend on what minerals happened to be nearby at that time. For example, granite is a mixture of quartz, feldspar, and plagioclase, while limestone is mainly composed of calcite and aragonite.

Combinations of minerals can produce a spectacular array of colors and patterns. Some natural gemstones may be multi-colored, mottled or sparkly. Others have smooth, muted and earthy tones.

Stones are available in natural irregular shapes or pre-cut into blocks for easy stacking.

the brick

Bricks are usually made of clay and come in a variety of colors - from red to gray, blue, yellow and cream.

Since they are the same size, it is easy to calculate exactly how many bricks you will need to build your raised bed.

Raised beds made of brick can be stacked horizontally in an interlocking fashion or angled to create a zigzag edge.

Using recycled brick in your garden is better for the environment (and your wallet). Your local Habitat for Humanity can be an excellent source of recycled building materials like bricks.

Metal

Metal raised beds are gaining popularity among gardeners who prefer their sleek, modern look. And they're super durable, lasting 30 years or more.

Like stone, metal acts as a heat sink that extends your growing season so you can garden in early spring and late fall.

Metal raised beds are a good choice in humid climates because they won't rot like wood. To keep your loft bed from rusting, always use galvanized metal.

Even if you don't like the steel look of metal loft beds, you can paint them a fun or neutral color to help soften the look.

oil storage tank

The easiest option for a metal raised bed is an oil storage tank. The tank is easy to install and requires no assembly, making it a great tank for feeding farm animals.

They come with round or rectangular edges and can be placed in the gardening spot of your choice. Just add some drainage holes in the bottom.

Water tanks can become permanent features in the garden, but are not too difficult to move. This allows for greater flexibility as your design ideas change with the seasons.

corrugated metal

Using some corrugated sheet metal, metal flashing, deck screws, and lumber (optional), you can build your own galvanized steel loft bed.

DIY It will give you full control over the finished size, height and shape of the bed.

There are a lot of tutorials out there - here's one for setting up metal panels inside a wood frame.

frameless

That's right, you don't necessarily need a frame to enjoy all the benefits of gardening above the soil line.

Hügelkultur is German for "mountain culture" and involves making mounds out of rotting wood, organic matter and compost.

After layering the material, the hill will be about 3 feet high.

Here's everything you need to know about building a hügelkultur loft bed.

You can create countless designs by stacking soil between paths—keyholes, concentric circles, spirals, and more.

The result is a charming and utterly unique loft bed that will add a lot of visual interest to the surrounding landscape.

5 Raised Bed Materials You Shouldn't Use

Whether you plan to grow food or flowers in raised garden beds, it's wise to avoid materials that can leach toxins into the soil.

Heavy metals and other chemicals can accumulate in the soil near raised beds, but they can also spread beyond the confines of the garden. Toxic pollutants are most mobile in clay, sandy, or moist soils and end up in the water table.

The first rule of gardening really should be: do no harm. Here are some of the worst raised bed materials that can have serious environmental impacts:

pressure treated wood

Before 2004, chromated copper arsenate (CCA) was the most widely used wood preservative. Discontinued due to concerns over arsenic exposure, Alkaline Copper Quaternary Ammonium (ACQ) is the standard wood treatment today.

Although it is far less toxic than its predecessor, ACQ contains large amounts of copper, which can leach into the surrounding soil.

Copper is highly toxic to fish and aquatic life, and using ACQ pressure-treated wood to contain wet soils increases the likelihood of copper leaching into watersheds.

MB tray

Wooden pallets are an inexpensive and waste-free way to build a bed—but watch out for those marked "MB."

Methyl bromide is a broad-spectrum insecticide, which is extremely harmful to human health. It is not recommended to use treated wood in any way.

It easily kills fungi, insects, roundworms, and even rodents. MB trays emit exhaust gases into the atmosphere, directly destroying the ozone layer.

In any DIY pallet project, indoor or outdoor, only use pallets that are stamped with "HT" or that have been heat treated. This means that the trays are sanitized at 132°F and above for at least 30 minutes. The HT Tray can be completely safely upgraded to a loft bed and beyond.

railway relations

Wooden railroad ties are treated with creosote, another harsh pesticide that should never be used around humans and plants.

Creosote is a soot that repels termites, fungi, and other pests. It is made from tar from coal, petroleum, and other fossil fuels.

Prolonged and frequent exposure to creosote railroad ties is not only harmful to human health, it can leach into the soil and cause damage to plants, insects and small animals.

cinder blocks

Cinder blocks made from fly ash or coal particles contain arsenic, lead, mercury and other heavy metals. While cinder blocks haven't been mass-produced in about 50 years, if you're using recycled materials for your raised beds, you might want to avoid them altogether.

Modern concrete blocks look identical to old cinder blocks, but are made of Portland cement and other aggregates. Concrete is considered non-toxic and safe for garden use. However, the concrete industry has a huge carbon footprint and is one of the major sources of CO2 emissions globally.

Efforts to upcycle trash into useful items are indeed admirable, but some items (like old tires) are usually best avoided in the garden.

Tires contain cadmium, lead, and other harmful substances that can theoretically leach into the soil. Some believe that old tires release most of their toxins during their first year on the road and take decades to degrade.

But the jury is still out on the issue. To date, no scientific studies have been conducted to determine whether old tires contaminate garden soil. But why take the risk? Especially when growing food using raised beds, it's better to be safe than sorry.

Once your raised beds are built and ready, the next thing you need to do is fill them with rich, healthy soil.

Finally, it's time to start planting - here are the best fruits and vegetables to grow in raised beds - and the worst!

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