How To Build A Gorgeous Deck Railing Planter Box

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Adding flowers or plants to your deck turns it into a relaxing oasis where you can let the stresses of the day just slip away — especially if you include soothing scents that help repel mosquitos like magic, like oil of lemon eucalyptus. And, if you enjoy DIY projects and love working with wood, why not try your hand at this beautiful deck railing planter box? 

Made from wood, this DIY planter box securely attaches to your deck railing, providing a place to plant colorful flowers. Alternatively, you can also use it to create your own at-home herb garden, which gives you an even better reason to use eggshells instead of throwing them away.

While there are a number of store-bought options available, most of them are made with plastic and can be very expensive depending on the size and style. Plus, they're also prone to cracking, especially when they have been sun-bleached for a long time. Unlike them, this DIY wood planter box is sturdy, long-lasting, and can be stained with a food-safe, low VOC stain — like the Netlea pure tung oil, available on Amazon for just $19.99 — that will add a beautiful finish without any harmful chemicals. Whether you choose to leave it unstained or you stain it, your new deck rail planter box can be a great addition to your home that adds a touch of beauty, and food for the pollinators too!

The supplies you'll need to make one 4-foot planter box are easy to find at any home improvement store. You'll need to purchase wood planks in cedar or redwood (both naturally rot-resistant), waterproof wood glue, like Gorilla Glue; weather-resistant deck screws; tung oil or milk paint for finishing; and deck railing brackets, like these window box brackets from Amazon. Most home improvement stores can cut the wood to your desired lengths, or you can make cuts at home using a table saw or bandsaw. If you're making your own cuts, make sure you exercise safety precautions, especially when making the narrow cuts. 

When assembling the pieces, apply the wood glue first, then secure the pieces together with deck screws for maximum stability and strength. Although you can use a nail gun for this, deck screws will provide better hold and are weather resistant. Once assembled, you can paint or stain the planter box if desired. 

To attach the planter box to your deck rail, first secure the window box brackets to the railing using deck screws. Then, place the completed planter box into the brackets. This bracket system will provide much better stability than top-mounting — especially when the planter is filled with soil and watered plants add extra weight.

Once you have built your deck rail planter box, it is time to fill it! Deciding what to plant can be a lot of fun, and there is a huge variety of flowers and herbs you can add to your planter box. That said, when choosing the plants and flowers for your box, you'll want to consider the amount of sun your deck gets and plan accordingly. 

Do you want to grow an herb garden? A few of the herbs that do great in pots include mint, an aromatic herb that repels spiders, as well as other options like rosemary, basil, thyme, and sage. If you want flowers with lots of pretty colors, you can choose varieties like marigolds, petunias, pansies, daisies, and small roses. The choices are endless.

Depending on how big your pots are, you can place several of them into your new deck rail planter box to add a variety of colors and blooms for a beautiful pop of color. Better yet, the design of the planter allows for rain to fall right through, allowing the flower pots to drain without pooling. This ultimately prevents your flowers from sitting in water and potentially rotting in the event of a big rain. Caring for your potted flowers and herbs is similar to ground planting, except that container plants typically need to be watered more often.