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If you plan to build a raised garden bed, the type of wood will play a role in how long it lasts. It will also impact its sustainability and how safe it is. This is especially important if you plan to grow food for your family. A garden bed can make your project a lot easier because you can control the environment and customize your soil.
Wood is the most popular choice for garden beds, as it is readily available, long-lasting, and relatively affordable. You can choose rot-resistant, long-lasting woods, such as cedar, juniper, redwood, and pine, or you might want dense woods, including black locust and white oak. Consider looking at locally sourced wood that is grown sustainably, and then make your selection.
Your wood choices will vary depending on where you live, so you need to do your homework. You want to choose the wood that is ideal in your region and will promote a healthy garden.
What to Consider When Selecting Wood for Your Raised Garden Bed
There are several factors to consider when you are choosing wood for your garden bed. You will often find that locally sourced wood from tree farms that are sustainably managed is the best choice and often cost the least. You can also look for wood that is FSC certified. This means that it is certified by the Forest Stewardship Council, which is a nonprofit that promotes responsible management of forests.
If you are considering treated wood, make sure that it is safe for food and your garden. Often, this type of wood is safe for fencing, but not necessarily for food. Finally, look for wood that is long-lasting and resists rotting. Some wood naturally handles the weather and outdoor conditions better than other types.
Is Pressure Treated Okay for Raised Beds?
Pressure-treated wood is treated in different ways, including the following:
- ACQ (Alkaline Copper Quaternary)
- CA (Copper Azole)
- MCQ (Micronized Copper Quaternary)
- SBX (Sodium Borate)
There is also older wood that is treated with CCA (chromated copper arsenate), and it was discontinued in 2003 because it contains arsenate, which can leach into your soil.
The newer products do not contain arsenic, but they do have copper and a fungicide. The fungicide helps to protect the food from soil fungus, while the copper keeps insects away. Although these woods are said to be safe, in some places you cannot grow organic food in any soil surrounded by pressure-treated wood.
If you do use pressure-treated wood, you can line the inside of the bed with heavy plastic. This will help to prevent any chemicals from leaching into your soil. However, if you are growing food in your bed, you should probably avoid pressure-treated wood and consider rot-resistant woods such as those listed below.
Best Wood for Raised Garden Bed
1. Cedar
Cedar is one of the most popular woods for building a raised garden bed. It has a rich fragrance, and it comes in varying colors, ranging from a pale white to light pink, tan, and a deep mocha brown. The different levels of tannin from the trees make each board unique and add interest to your beds.
Cedar also has knots of different sizes, which gives it character. It is also rot-resistant. It doesn’t absorb water as quickly as softer woods, and the oils in the wood make it resistant to insects and other pests. It has its own natural defenses that make it ideal for garden beds.
The other characteristic that makes cedar so popular is that it has a great deal of linear strength. It is strong and will not bend or break as easily as softer woods. Cedar looks great and has properties that make it long-lasting and rot-resistant, so it is one of the most popular woods to use.
2. Redwood
Redwood is another popular wood used to build raised garden beds. It also lasts a long time and looks great. It can be more expensive, as it is a more limited resource, but it is safe, durable, and resists rot and insects. It also resists termites and water damage.
One of the reasons that redwood is so popular is that it is unnaturally strong yet easy to work with. It can last as long as 20 years without damage from insects, water, or other pests. It is a reddish-brown color, and it doesn’t need to be treated. In spite of its strength, it is easy to cut, saw, and drill.
3. Douglas Fir
For people looking for a more inexpensive option, Douglas fir is a great choice. It is durable enough to last between five and seven years, and it has some rot resistance. However, it can fall victim to insects. It is light brown, reddish, or yellowish-brown in color, and it is easy to cut and drill.
Another benefit to using Douglas fir is that it is abundant and sustainable. Forests full of Douglas firs are found throughout the West Coast of the United States, and they have no trouble regrowing after wildfires or timber harvests. It is one of the more sustainable types of wood, and it is environmentally friendly to use it.
Finally, Douglas fir resists garden rot. It has resins that protect it from decay and infestations of pests. It won’t decompose after exposure to moisture, and it doesn’t expel toxic chemicals into the soil. This makes it a great choice for people who are building a raised garden bed.
4. Black Locust
Black locust is hardwood, and it grows in the United States. It is in high demand, which makes it a little more expensive, but it is resistant to rot naturally and quite durable. It can be light green to dark brown in color, and it is very durable. It is hard to work it by hand, but you can use machines.
You won’t have to worry about insects or rot, and black locust trees grow more quickly than other types, so it is more sustainable. It can last between six and 10 years, and it is safe to use when you grow your garden.
5. White Oak
Another type of hardwood that works well in raised garden beds is white oak. It has some natural resistance to moisture and rotting, even when it is untreated. It lasts longer if it is oiled or painted, but you must use a non-toxic, water-based product. You should also use a liner in the bed if you choose to paint your wood.
White oak appears light brown to medium brown in color, and it is durable. It is difficult to work by hand, but you can use machine tools to cut it. It is moderately priced, and it is a popular wood.
6. Eastern Hemlock
If you live in the northeast, eastern hemlock is a popular wood that lasts up to seven years. These trees are very common in New Hampshire, and hemlock is sturdy, rot-resistant, and durable. Eastern hemlock is coarse-grained and uneven in texture, and it is lighter than other woods.
It is light brown to buff in color, and it can splinter when you use tools. Its wood glues easily, and it holds nails well. If you live in an area where eastern hemlock grows, it is easier to get and an affordable option.
7. Juniper
Another great option for a raised garden bed is a juniper. Juniper is naturally resistant to bugs and rot, and it handles the soil well. It is safe to use for organic growth. Juniper is rustic in appearance, so the wood isn’t smooth, and the edges aren’t perfect. It is more natural-looking. If you live in a place where juniper is plentiful, such as the Pacific Northwest, it is a durable and practical wood to use.
Juniper has naturally occurring oils that protect it from pests and moisture, but it doesn’t harm your vegetables or other plants you grow in your garden bed. It is attractive and adds character with its rustic appearance and it isn’t difficult to work with. However it can be heavy, and it is usually a rough cut, so the pieces don’t fit together perfectly.
8. Pine
Pine is popular for making a garden bed for several reasons. It is easy to work with, and it is readily available. This makes it less expensive than other types of wood. You can find it at most lumber yards and hardware stores, and it comes in varying sizes. This makes it easy to customize your garden bed.
It is important to understand that pine is less resistant to rot than other types of wood. You will likely need to replace it in about five years. However, the cost of pine is low enough to make it a practical option for many people who build a raised garden bed at home.
Pine is one of the most readily available and affordable options for garden beds. It is also easy to work with. It is durable but more pliable than other woods. It comes in different varieties because there are different types of pine trees. It comes in different colors and textures, so you can find a unique combination.
9. Spruce
Spruce is a type of pine, and it is popular for building a raised garden bed. It is easy to work with, and it is strong enough to hold your garden bed. When spruce is cut, it dries quickly, and it has a whitish-yellow color. It is durable, and it has visible rings.
Sometimes, you will find spruce that has been heat treated. This is different from pressure-treated wood in that it doesn’t involve any chemicals. It is a heat process that dries the wood more quickly. This helps to ensure that the wood has no insects in it and is ready for use.
As is the case with pine, spruce will need to be replaced in about five years. However, it is an affordable option that is readily available, and people find it easy to work with.
10. Cypress
Cypress wood is a pale yellow to dark reddish-brown in color, and some varieties look almost black. They say that darker colors are more resistant to decay. This type of wood is durable and stable. It does well in moisture, and it will hold up when you use it for a raised garden bed.
Cypress isn’t as common as other woods, but it has rot-resistant and insect-resistant properties that make it popular. It lasts longer than pine, and it is affordable if you can find it locally. It is often used as an alternative to cedar because it has a similar aesthetic at a lower cost.
11. Chestnut
Chestnut wood is found in the eastern United States. The heartwood is between light and medium brown, and it gets darker with age. It can end up being a reddish-brown color. The sapwood is pale white to light brown. It has a grain that is spiral or interlocked, and the texture is coarse and uneven.
Chestnut is porous, but it is rated to be very durable. It is easy to work with whether you use hand tools or machine tools, but it does split easily, so some people use glue. It is more expensive because it is rare. In the early 1900s, blight knocked out a lot of American chestnut trees, so wormy chestnut (chestnut that was previously damaged by insects and worms) is often found. It is salvaged from older structures and sold as reclaimed lumber.
12. Catalpa
Catalpa is an ornamental tree, and it looks similar to ash or oak, but it is much lighter. The trunk of the catalpa tree is mostly heartwood, and it varies from shades of tan to golden brown. It has wide growth rings, and there is a great deal of contrast between older trees and younger trees.
The wood is durable and stable, and it is rot resistant. It is known to hold up well when it has direct contact with soil and moisture. There isn’t really an organized market for catalpa, so the price can vary widely. If you have access to it, it is easy to use, but it can be difficult and expensive to find. It works well in a raised garden bed because it is light, attractive, and holds up well outdoors.
13. Yew
Yew is a popular choice because it also resists rot and decay. It is a species of evergreen tree, and it is an orangish-brown to dark brown color. It can have interesting purple streaks through the wood. It is considered a softwood because it is a pine tree, and it is more common in the Pacific west.
Yew trees are usually small, and they have unique shapes. This makes lumber less common, so it is relatively expensive. It has properties that are similar to pine, but it is hard and resilient. It has an above-average ability to resist decay and rot, and it can be used in your raised garden bed.
14. Black Walnut
Black walnut is a dense, durable wood, which works well for a garden bed. It has the ability to resist rot and decay, and it is very attractive. The interesting thing about the black walnut tree is that it is toxic to plants. They produce juglone, which kills plants such as tomatoes, potatoes, peppers, chilies, eggplant, and more.
It is one of the densest and long-lasting types of wood to use in a raised garden bed, and its heartwood ranges in color from a pale brown to a dark chocolate brown. The sapwood is often pale yellowish-gray to white, and it has grain patterns. It is used because it is easy to work with, and it is one of the most durable types of wood. It is more expensive than other types, as it is considered premium wood.
Wood to Avoid for Your Raised Garden Bed
If you come across some recycled or reclaimed wood, you need to make sure that you find out whether it has been stained or painted in the past. Some reclaimed wood may have been treated with lead or other toxins, which can leach into your garden and harm your plants.
You should also avoid other CCA pressure-treated wood. You can use newer pressure-treated wood, but it isn’t advised. If you plan to grow an organic garden, you need to make sure that you are using wood that is safe for your plants.
You can always line the garden bed with heavy-duty plastic. However, choosing a wood that is locally sourced, sustainably farmed, and within your budget is always ideal.
You can find alternatives to wood, but it is important to do your research and make sure that the materials are eco-friendly and safe for the plants you are growing. When you are deciding what wood for garden beds, cedar is the most popular because it is so durable and resistant to pests and rot. It looks great and is easy to work with. However, any of the wood listed above will work.
Sources
- https://www.bhg.com/gardening/landscaping-projects/garden-structures/organic-raised-beds/
- https://www.jwlumber.com/2018/04/25/best-lumber-for-garden-box/
- https://theraisedgardenbed.com/2020/06/25/what-is-the-best-wood-for-raised-garden-bed/