When choosing a window box it is essential that you have all the information in front of you. First off, there are many materials to choose from: wood, vinyl, PVC, fiberglass, aluminum, wrought-iron, and copper to name a few. Wooden window boxes are the old standard that have been around for centuries and they're an affordable solution to window box planting and gardening. The advantages are that they can be painted, they can be made custom, and they are often affordable.
The disadvantages are that the average wood window box lasts 3-5 years and usually shows signs of rotting after just 2 years. They will require a liner inside and they are vulnerable to splintering, warping, fading, peeling, moisture, and insects. The ideal choice for a wooden window box is either cypruss or cedar. Both woods have the ability to resist rotting and will help the window box last longer than other woods.
Vinyl window boxes are an alternative to wood that is a no rot solution to window boxes. Vinyl is resistant to moisture, however, vinyl window boxes usually do not accept paint, have a shiny appearance, and are made from thin double walled material that can crack over time. Vinyl is a great choice for someone who wants a no rot planter that needs to be white and lives in an environment where temperature changes are minimal. Although vinyl window boxes are not ideal for supporting heavy loads they are lightweight and easy to install and many smaller sized boxes can easily be clipped to a window with accessory brackets. Vinyl has many advantages over wood and is an affordable no rot solution to window box planting. PVC window boxes are an upgrade over vinyl in that they are made from solid core material that makes them more durable and prevents them from splitting, cracking, or warping over time.
Additionally, PVC window boxes are also moisture and rot free. Unlike vinyl, they have the ability to accept paint readily and they have a matted finish to them that keeps them from looking like plastic. In fact, they often look like wood after being painted. The disadvantages are that they are heavier than vinyl and can cost more on average. Fiberglass planters offer many of the advantages of PVC window boxes in that they will not rot and are moisture resistant. The advantages of fiberglass window boxes are that they are available in custom sizes and they can usually be painted as well.
The disadvantages are that they are generally heavier, limited in availability, and pricier of all the options. They can be more difficult to install, especially for larger boxes. They tend to have a glassier finish to them, but they can usually be painted. Next, that takes us to aluminum, wrought-iron, and copper window boxes.
Aluminum is an upgrade over wrought-iron in that it can be sprayed black to look like iron but will never rust. A wrought-iron window box will generally show signs of rust in 3-5 years and may require maintenance. Metal window box cages will need liners to hold potting soil directly or they can be used to hold potted plants instead.
Some metal window boxes are bulk manufactured in certain sizes and are made affordable at that size. However, custom sizing can be pricey or limited in availability. Copper window boxes tend to be pricey, but offer a very distinct look that cannot be substituted in any way. With so many new materials on the market it's important to understand the advantages and disadvantages to all of your choices. Whether you're look for affordability, low maintenance, or a distinct look, window box gardening can be a fun hobby that brings lots of joy into your life.
Matthew Buquoi is the owner of Flower Window Boxes, a manufacturing company that specializes in affordable window boxes, PVC window boxes, and custom window boxes. He has built and installed window boxes of all sizes, shapes, and types and regularly writes about window boxes and window box gardening.