Window Box Liners: Why, When, How To Use Flower Box Inserts

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Flower or window box liners are plastic trays or sheets of coconut fiber material used to line the bottom of flower or window boxes and planters before potting plants with soil inside.

There are so many reasons to use liners, especially in places where the weather conditions are extreme. Wonder if you should use liners in your window boxes? 

window planters made of wood are perfect candidates for window box linersPin
Wood window boxes make perfect companions for window box liners

If you’re looking for a low-care solution for your window boxes, consider succulents or even faux flowers. Well, read on to learn more.

Why Use Windowbox Liners?

Using liners for flowers or a window planter box serves some practical purposes. 

In addition to PVC, we have also introduced a line of wrought iron window box planters and cedar window boxes to help you create the perfect design. Because our PVC flower boxes are impervious to bugs, rotting, and moisture, you can plant directly inside them.  



Throughout their long history, window boxes have been used to add a more aesthetic appeal to the home. They appear on the list of inexpensive and easy ways to add curb appeal and a more cohesive look to your house.

If you’re adding some patio containers or window boxes to your home, be sure that you know which flowers are perfect for hot, sunny spots and which grow best in the shade.

 White window boxes tend to show off plants and flowers more. However, some homes may benefit from having a planter painted to add some contrast. 

Our cellular PVC composite material has a matted finish, making our products look like wood instead of shiny plastic.  

PVC window boxes can be painted, come in over 30 lengths, sizes, and custom sizes, and can be customized with self-watering options. Over a dozen different designs to choose from. 

Their prolonged exposure to moist conditions may cause their surfaces to deteriorate, rust, or rot and thereby break apart in due time. 

Window box liners are essential elements helping to extend the longevity of the window box by preventing direct contact of the container with the organic materials and water used by the plants.

Colorful window flower box on a sunny day.Pin
Photo Credit: Instagram @plaids.and.poppies

Ideally, liners should have holes at the bottom that match those of the boxes to drain excess water. If water pools at the bottom of the “unlined” window box planter, adding the liner is beneficial.

Plastic lining can help avoid this problem and keep your planter dry no matter how many times you water the indoor plants.

Window box liners made from coconut fiber are similar to hanging basket liners. 

One of the best window box flowers for the full sun is the petunia. These vigorous annuals only need a little space and will happily bloom all season. Here, soft pink double petunias look stunning, spilling out of a window box, along with a darker pink verbena and chartreuse sweet potato vine.  

This material is designed to hold water like these coco liners for window boxes, that release water slowly to allow the plants to take root. 

Because the liners are porous, they allow for good drainage and aeration. Coconut has anti-fungal properties as well, which is helpful in preventing plant diseases.

More importantly, plastic planter box liners and coconut liners make transferring plants from one container to another so much easier for you. Trim around the top and bottom of the box were added for artistic finishing touches. Many in this collection offer a classic look with self-watering convenience. 

Rotating plants as the seasons change becomes less messy. It takes a shorter amount of time since you can easily lift the flower pot liners up and transfer them to a different box, pot, planter, or even terra cotta container. 

You can also pre-plant new blooms beforehand so they are ready to be placed in your window when the right time of year rolls around.

When To Use Planter Box Inserts

With all the new planter box liner material found today in the garden, you may have a PVC window box or one made from plastic. However, that does not mean using liners will not help.

You can use planter liners all throughout the year. Even copper and planters with a medal powder coating on them will benefit. 

In fact, experts recommend using liners throughout the year, even if you do not swap flowers seasonally to extend the life of your window boxes.

Window box flowers on light blue shutters.Pin
Photo Credit: Instagram @charlestonspired

Turn up the texture and elevate your home’s exterior in one fell swoop with these woven resin window box planters from Hayneedle. In your choice of colors and sizes, our selection of window boxes is perfect for foliage plants and flowers. 

Plus, making DIY window boxes allows you to customize them to the exterior of your unique abode, for every style, from contemporary to colonial and beyond. 

Plant pot liners can be used to pre-pot small plants for the coming season, such as spring bulbs you want to prepare during the winter. 

If you want to change the look of your house or windows by switching flowers, you can easily do so without uprooting and throwing away perfectly healthy plants.

Simply tuck in another liner of the blooms of your choice and store the other one in your shed or keep it indoors.

How To Use Flower Box Liners

Window or flower box inserts install easily in a couple of minutes.

First, make sure the liners are the size that can fit inside your box.

Here are a few examples of the most common sizes in both plastic and coco fiber:

Colorful flowers in a window box against a yellow wall.Pin
Photo Credit: Instagram @charlestonspired

Coco liners are more flexible and come in round shapes to fit hanging baskets and other shapes of plant troughs, similar to rectangular plastic planter liners.

You can also find plastic window box liners made of thin, flexible material you can clip to the side of the window box to prevent it from folding on itself.

Prior to potting, make sure the liners have drainage holes. You can make it yourself if the liners do not have any.

Low maintenance is the name of the game with miniature Fraser firs since they grow almost anywhere as long as they get a few hours of sun every day. These dwarf trees look wonderful in a window box mixed in with flowers and other plants. 

To make installation even easier, pot your plants inside the liner while they are outside the box. Through this, you could move the licorice plant around and pat them down with little effort.

When filling the lining with soil, avoid overfilling it by keeping the soil a few inches below the lining level. After planting the plants safely inside the liner, you can easily slip the whole thing inside your window or flower box.

Having small planter box liners is not an excuse not to use them. Liners come in all sizes, and coconut liners are soft and flexible enough to be made to fit any size of the box you have. You can also cut plastic liners along the top so that they do not peek out from the window box.

Colorful flowers in window box on urban streetPin
Photo Credit: Instagram @thecharlestonlens

Liners are simple yet effective tools for keeping your plants healthy and manageable. They:

  • Promote water retention and good drainage at the same time
  • Prolong the life of wooden flower boxes
  • Allow for easy potting and installation of plants
  • Make the rotation of seasonal blooms so much easier

The most popular names in liners, plastic, or coconut are: AquaSav, Poly-Pro, Pennington, and Bosmere

They are also very affordable. With all these advantages, there is no excuse not to use flower box liners in your home and garden. 

Make gardening easier and more convenient with raised garden beds. Grow fruits and vegetables anywhere and avoid digging up your lawn.  

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