How to Build a Wooden Planter Box

Planter boxes, also known as raised beds, are a convenient way to grow a variety of plants and vegetables. In addition to providing a defined space for your garden, a planter box contains loose soil that drains well—an ideal environment for healthy plants.

While most garden vegetables grow fine in planter boxes, there are a few types of plants that do particularly well. Because the surface area in a raised bed is limited, plants that grow vertically and take up less space are ideal. By adding a simple trellis, you can easily grow pole beans, peas, zucchini, small melons, and cucumbers, and tomatoes and peppers that are staked or placed in cages stick to their own area when tended. Root vegetables also do well in planter boxes—potatoes, carrots, onions, and radishes grow easily in the box’s looser soil.

Planter boxes come in a variety of sizes. The length will depend on your available space and how many plants you want to grow. As a rule, most planter boxes are no more than four feet wide—this ensures you’ll be able to reach far enough across to plant, weed, and tend your garden. As for depth, six inches is the absolute minimum. Any shallower and the roots will have nowhere to go. Twelve inches deep is ideal.

If you’d like to try your hand at building a wooden planter box, a simple 4’ x 6’ version can be completed in just a few hours. Follow the instructions below and repeat as necessary.

Materials needed to build a planter box

Two 2’ x 8’ boards, cut to four feet long
Two 2’ x 8’ boards, cut to six feet long
Six 18” wooden stakes
Saw
Wood glue
Drill and 3” galvanized wood screws

How to build a planter box

Lay out the wood in the area where you plan to put the planter box—preferably in a flat, sunny spot.
The boards will be joined at the corners. Pre-drill holes in the edges of the boards to keep the wood from splitting when they are screwed together.
Apply a few beads of wood glue to the edges where the wood will be joined.
Attach the wood by with galvanized wood screws.
Place wooden stakes in each inside the corners of the box and in the middle of the longest walls. Push into the earth and drill in place. This will reinforce the raised beds and keep it from moving when you add soil, water, and plants.

How to start planting

Once your planter box is complete, it’s time to fill it. Begin by adding soil that includes a variety of organic materials, such as manure, compost, and other amendments. Aim for two parts soil to one part compost for the healthiest balance.

Next, add your plants. When placing your vegetables in your boxes, put the tallest plants on the north side of your bed so they don’t shade the smaller plants in front of them. If possible, opt for disease-resistant plants when possible. Because plants in raised beds are close together, diseases can spread more quickly. You’ll want to nip these in the bud.

If you’re buying a planter box

If you don’t have the time, energy, or desire to build a planter box from scratch, you can buy one that’s ready to go. As you shop keep in mind the size and weight of the box—don’t buy something you won’t be able to transport to your home or move around your yard. Avoid pressure treated wood, as it contains chemicals that can leach into the soil, opt for boxes with adequate drainage, and make sure it’s deep enough to grow strong, healthy roots.