Taking this into account, we evaluated products on their ease of installation, as well as their size, drainage, mounting options, and durability. Our top choice is the Mayne Fairfield Self-Watering Window Box, which is available in multiple sizes and colors, has a self-watering design, and is backed by a 15-year warranty. Here are the best window boxes to dress up your home. For classic window boxes that look good on any home, you can’t go wrong with the Mayne Fairfield Self-Watering Window Box. It’s made from durable polyethylene that can withstand a wide range of temperatures and is treated to resist fading in the sun. The box comes in several sizes, ranging from 36 to 60 inches wide, as well as basic color options to match your home’s exterior. The four wall-mounting brackets can be installed underneath your window, and the supports are black with a powder-coated finish. These window boxes’ distinctive double-walled design creates a water reservoir underneath the planting area, helping retain moisture and encouraging root growth. The self-watering design helps your plants thrive during summer and reduces how often you need to water. The boxes are made in the USA, and they’re backed by a 15-year limited warranty. Price at time of publish: $120 These window boxes are extremely lightweight, weighing just a little over 2 pounds each. They don’t come with mounting brackets—you need to purchase compatible supports if you plan to install the planter underneath a window or on a railing. But the good news is, you have plenty of options, as the box is a fairly standard size. Overall, it’s a great value for basic window boxes that can be used for a few seasons outside your home. Price at time of publish: $13 These crack-resistant planters are lined with a styrofoam insulation that helps retain moisture during the hot summer months. They’re rated for use in temperatures anywhere from minus-30 to 125 degrees Fahrenheit. Each window box has a drainage hole in the bottom that can be plugged up with the included stoppers. There’s no denying that these window boxes are beautiful and well-made. Price at time of publish: $130 The included adjustable steel mounting brackets can be installed on a wall or deck railing, and they come with cross-braces that prevent the planter from bowing. Large refill tubes allows you to add more water to the reservoir as needed, and their durable construction should hold up for many years. However, you need to clean out the planters before winter if you plan to leave them outside. Water left in the reservoir freezes and can crack the plastic. Price at time of publish: $40 These stainless steel window boxes are rust- and weather-resistant, but the manufacturer recommends installing them in a covered, shaded area for best results. (The metal likely gets hot if it’s in direct sunlight, which could harm your plants.) The planter has a drainage hole in the bottom for excess water to run out, and the manufacturer recommends lining the box if you plan to plant directly inside it. These flower boxes come with the necessary hardware to mount them to the wall, allowing you to display them on the side of your home. If you plan to plant directly inside the window box, you need to put some type of liner in it first, as there are slight gaps between the wooden slats. Just be sure to account for drainage. Alternatively, you could simply place plants in nursery pots inside the box. This plastic window box is flexible and impact-resistant, and includes the hardware needed to hang the box on a wall or railing. (However, the railing brackets don’t fit properly on smaller metal railings, so you may need to purchase different hardware.) It has a water plug on the bottom that allows you to drain off excess water, and at the end of the product’s usable life, it can be recycled, keeping it out of the landfill—always a plus! Price at time of publish: $40 These planters are designed to be hung over railings on your porch or deck—unfortunately, they don’t include the hardware necessary for wall-mounting. The adjustable brackets fit most flat railings 2 to 6 inches wide, and they can be installed without any tools. You can fill the liner with dirt and plant directly inside it, and the natural fiber lets any excess moisture pass through, so you don’t have to worry about drainage. However, you may need to replace the liner each year. Price at time of publish: $34 Once put together, these window boxes have a classic design with a large upper lip, and the vinyl material is treated with a UV inhibitor that prevents the color from fading. The planter’s built-in water reservoir at the bottom helps keep your plants watered for longer. The manufacturer backs the product with an impressive 15-year warranty for residential applications. Price at time of publish: $440
Material
Window boxes can be made from a variety of materials, each of which offers its own benefits. Common materials include plastic or metal frames with a fiber liner, allowing them to be lightweight and easy to install. “Plastic window boxes tend to hold water for longer periods of time," Lindsay says, “while those made of frame and liner will need to be watered more frequently.” Metal window boxes are more durable in the long run, but they can get hot when installed in direct sunlight, which can ultimately harm your plants. You can also find wooden window boxes, but they tend to be expensive and heavy, requiring heavy-duty mounts.
Size
When selecting a window box planter, Lindsay says, you can usually set one up a few inches wider or narrower than your window, “since the plants will ‘blur’ the edges.” Measurw your window width prior to shopping. Also consider the window box’s capacity. If you’re planning to fill it with soil and plant directly in it, you need to buy the right amount of potting mix, as well as a suitable number of plants to make the box look full.
Installation
As you compare different window boxes, be sure to consider whether they come with mounting brackets and necessary hardware, and if so, where the brackets can be used. Some are only designed to be mounted on a railing or windowsill, while others can be hung on a wall. Depending on the style of brackets, you may also need special tools for installation, such as a bit to drill into brick.
Why Trust The Spruce?
This article was written by Camryn Rabideau, a freelance writer and product tester for The Spruce. An avid gardener, she’s purchased many outdoor planters in, and she used her experience to select well-designed window boxes from trusted brands. She also spoke with Lindsay Pangborn, Gardening Expert at Bloomscape, for insights on what to look for in a window box and which types of plants to put in these outdoor planters. She evaluated each window box on factors such as its material, size options, aesthetic, and durability, prioritizing models that provide adequate drainage for the plants inside.
“Window boxes that will receive more than 4 hours of direct sunlight should be filled with full sun plants. A few popular recommendations are petunias, geraniums, and pansies, which will produce more blooms with the more sun they receive.”
