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Best Indoor: MyGift 10-inch Rectangular Red Ceramic Succulent Planter
What's nice about using a window box inside is that you can choose to go with a more decorative material, like the ceramic used for this minimalist-looking planter. If red isn't your thing, the planter also comes in four other colors. It comes with a removable tray and has two built-in holes for drainage.
These planters work well for both succulents and small houseplants and hold approximately three to seven small cacti or two small African violets. Some shoppers have even used them as wedding table centerpieces, and others report that the planter is sturdy enough to sit outside on a deck as long as the temperatures don't drop below freezing.
Best Splurge: H. Potter Copper and Wrought Iron Window Box, 30 Inches
It has a high price tag, but rather than corrode, this 30-inch hand-crafted window box will only get better with time since it's made from rust-resistant stainless steel and covered in a copper finish. The box fits in a weather-resistant wrought-iron frame, and there are drainage holes to help keep plants from getting too soaked. Mounting hardware is included, and there are brackets that make it easy to remove the box when you need to.
H. Potter is a family-run garden decor business based in Idaho, and the company is known for its excellent customer service. According to customers, these planters are well worth the extra money as the quality is unparalleled and they look gorgeous no matter what you put in them.
Best Wrought Iron: Gracie Oaks Noles Wrought Iron Window Box Planter
This elegant-looking wrought iron planter, which is covered in a powder coat finish that's designed to resist the elements, is reminiscent of the window boxes in Paris and the French Quarter of New Orleans. It has a sturdy frame, weighs 16 pounds, and is meant to hold three individual flower pots. A 12-inch pot in the middle can be flanked by a pair of 8-inch containers on either side. It measures 30 inches long and has multiple mounting holes for securing it, although it doesn't come with hardware, so you'll need to supply your own to attach it properly. Even without the included hardware, customers are quick to report that this window box was beautiful, sturdy, and well-made.
Best Self-Watering: Lechuza Balconera Self-Watering Window Box Planter
This window box gets its charm from the wicker-like texture (it's actually tough plastic), but the slate gray color gives it a modern feel. It's 31 inches long and can be placed on the ground or mounted in front of a window. Note that the brackets, which fit into the back of the planter and aren't visible from the front, must be purchased separately. To make planting easier, the box comes with a removable liner that has retractable handles.
Another selling point? There's a self-watering system: a reservoir directs water when it's needed, and gardeners can check the indicator level to see when they're due to refill it. A drainage plug helps you get rid of extra rainwater after a big storm, cutting down on the potential for root rot, and each window box comes with a package of Lechuza's plant substrate, designed to go between the potting soil and the reservoir to help aerate the roots. If the gray hue doesn't work with your color palette, this window box also comes in white and dark brown.
Best Basic: Mayne Nantucket Polyethylene Window Box, 3'
With its crown molding details and glossy black exterior, this 3-foot window box would look great on many kinds of buildings, including a brick townhouse or a classic 19th-century home. It's also sold in a crisp, beachy white and a more mellow off-white, which the company calls "clay." This planter is tough enough to stay out all year, as it's made from rugged polyethylene hard plastic that contains UV-inhibiting resin to help it resist fading, and can be easily cleaned with a rinse from the hose. The three steel brackets are also covered in a powder coat finish to help them withstand rain and snow. Like the Balconera, the Nantucket window box has a self-watering system and uses a 2.5-gallon reservoir that helps take some of the guesswork out of plant care. When used in a residential home, Mayne offers a 15-year warranty on their window boxes.
Best Extra-Large: Mayne Self-Watering Yorkshire Vinyl Window Box
Sometimes you need to go big with your window boxes, and if that's the case, this 6-foot option is an attractive, sturdy option. It comes with an assembly kit containing just about everything you need to install it: panels, end caps, vinyl glue and five mounting brackets with screws that have a weather-resistant finish. Decorative brackets can also be bought separately and added for extra oomph. There's a self-watering reservoir at the bottom, and the box is made from vinyl with UV-resistant material, so it should last for several seasons. Should you have issues with your window box, it's covered under Mayne's 15-year residential warranty. The one downside? It's only available in one color.