Window boxes add instant brightness and charm to the exterior of your home, allowing you to display beautiful seasonal blooms. Since adding a window box is not easy, we consulted with Lindsay Pangborn, Gardening Expert at Bloomscape, for expert advice. “Drilling into the siding of your home will be required for most window box installations,” Lindsay says. “Be sure to do this properly, since incorrect installation can lead to water seeping into your walls.”
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.
Best Overall: Mayne Fairfield Window Box Planter
Multiple sizes and colors
UV treatment prevents fading
15-year limited warranty
Pricey for plastic construction
Who else recommends it? HGTV also picked the Mayne Fairfield Self-Watering Window Box.
What do buyers say? 89% of 600+ Amazon reviewers rated this product 5 stars.
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.
Best Budget: Dynamic Design Newbury Black Resin Window Box
Brackets sold separately
You can keep things simple and sweet with the Dynamic Design Newbury Window Box. This resin planter has an extremely basic design that comes in a few different colors, and its attached saucer on the bottom catches water from the drainage holes—ideal if you place the window box where that you don’t want it to drip.
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.
Best Splurge: Veradek Metallic Series Corten Steel Window Box Planter
Develops rust patina
Optional drainage hole
Insulation foam maintains moisture
Suitable for year-round use
Brackets not included
For eye-catching window boxes your neighbors may envy, the Veradek Metallic Series Corten Steel Window Box Planter is a worthwhile splurge. These high-end window boxes come in two sizes—48 or 36 inches long—and they’re crafted from heavy-duty thick-gauge corten steel. Not only does this make them extremely durable and long-lasting, but also, the metal is designed to develop a rust patina over several months, creating a beautiful rustic finish. (The window boxes arrive in their bare state.)
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.
Best Self-Watering: Gardener’s Supply Self-Watering Window Box
Built-in water level indicator
For those who sometimes forget to water their plants, the Gardener’s Supply Self-Watering Window Box helps keep your blooms happy and healthy. It’s 39 inches long and made from frost-resistant plastic, and the planter comes in white or terra cotta finishes. In addition to holding up to 28 quarts of soil, this window box has a built-in 9-quart water reservoir that automatically keeps your plants watered. You can monitor when the reservoir is low thanks to its easy-to-read water level indicator.
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.
Best Metal: Grandin Road Stainless Steel Window Box
Multiple sizes available
Highly durable design
Rust- and weather-resistant
Can mount to window, wall, or deck
Recommended for covered areas
Metal window boxes are more durable than plastic ones, and the Grandin Road Window Box is sure to last for many seasons, thanks to its sturdy stainless steel construction. It comes in three sizes—24, 36, or 48 inches wide—and graphite or copper finishes are available. These planters have a detailed silhouette that look elegant on the exterior of your home, and they can be mounted on a wall, window, or deck using the included brackets.
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.
Best Wooden: IKEA STJÄRNANIS Flower Box
Multiple sizes and finishes
Sturdy wood construction
Needs liner for direct planting
If you don’t like the look of plastic window boxes, consider the STJÄRNANIS Flower Box, made from solid acacia wood. The boxes are available in two sizes and two finishes, and despite being made from sustainably sourced wood, they’re still surprisingly affordable. The wood has been treated with a layer of acrylic stain for outdoor use, but you may want to re-stain it each year to ensure it stays in good condition.
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.
Best Plastic: Veradek Plastic Window Box
Multiple colors available
Made from recycled materials
UV treatment resists fading
Includes hanging hardware for walls and railings
Doesn’t fit all railings
While not the most durable, plastic products, such as the Veradek Plastic Window Box, are lightweight and reasonably priced, making them popular choices for plant lovers who want several window boxes. This particular window box comes in three different finishes and can be purchased in sets of one or two. While it is made from plastic, the construction uses all recycled materials. The single-wall design has a classic rectangular shape that’s slightly tapered at the bottom, and the plastic is treated with UV inhibitors to prevent the colors from fading.
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!
Best Trough: Winston Porter Kartz Metal Railing Planter
Easy to install
No wall mounting
The Winston Porter Kartz Metal Railing Planter has a trough-style design, featuring a metal frame and eco-friendly lining. It's available in 24- or 36-inch widths, and you can’t beat the reasonable price, especially if you want to buy more than one. The planter is made from powder-coated metal that can withstand being left outside, and the rustic liner is made from coir, or coconut fiber.
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.
Best Custom Size: Mayne Self-Watering Yorkshire Vinyl Window Box
Multiple large sizes available
Can be cut to exact window length
Most window boxes come in standard sizes, including 24 and 36 inches wide. But if you have a uniquely sized window, the Mayne Yorkshire Self Watering Vinyl Window Box is one of your best options. Not only does this vinyl planter come in a wide range of sizes, up to 7 feet long, but it also can be cut during assembly, allowing you to tailor the length to match your window. The flip side, however, is a fair bit of assembly is required—the window boxes don’t arrive ready-to-hang.
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.
With a convenient self-watering design and classic appearance, the Mayne Fairfield Self-Watering Window Box is our Best Overall. This window box comes in a variety of sizes and colors, and it includes the hardware needed to mount the planter to the wall of your home. for a more budget-friendly option, consider the Dynamic Design Newbury Black Resin Window Box. It has a simple design with an attached saucer, but it doesn’t come with brackets for mounting.
What to Look For in a Window Box
The most important factor to consider when selecting a window box planter, says Lindsay Pangborn, Gardening Expert at Bloomscape. is to make sure the box has drainage holes or a natural liner—such as one made of coir—to remove excess water. “Discouraging excess water helps to prevent root rot, which ultimately can lead to plant death," she advises. It’s best to look for a window box that has multiple drainage holes along the bottom of the planter, as this allows excess water to seep out.
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.
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.
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.
How do you hang window boxes?
Most window boxes come with brackets designed to be mounted to the exterior walls of your home, using screws. Mount the brackets into studs, as a window box filled with soil and water can be quite heavy. It’s also important to follow the directions precisely to avoid damage to your home’s siding. “Be sure to [install the window box] properly," Lindsay says, "since incorrect installation can lead to water seeping into your walls.”
What types of plants can you grow in a window box?
When considering the types of plants for your window box, first consider how much direct sunlight it is expected to receive throughout the day, Lindsay advises. “If your window box will receive 4 hours or less of direct sunlight, look for shade plants like caladiums, ivy, torenias, or begonias.
“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.”
Should window boxes be wider than the window?
What looks best is a window box the width of the window up to a couple of inches more on each side, or to the point where the window trim ends.
How do you hang window boxes on brick?
If your home has a brick exterior, you need a few extra tools to securely mount your window boxes. A masonry drill bit allows you to pre-drill holes into the hard material, and a combination of plastic anchors and lag screws ensures the brackets are secure and able to hold up the weight of the window box.
What vegetables can you grow in window boxes?
How deep do window flower boxes need to be?
For aesthetic purposes, a window box with a depth of about 25 percent of the window's height is most flattering on the home. It's also important to consider the plants you intend to include in your window box; plants with more robust root systems require a deeper box than one used for herbs. Eight to 12 inches is typically appropriate for most window-box plants.
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.