How to Design a Window Garden

If you enjoy the company of houseplants, consider cultivating a window garden, which is ideal for showing off plants in the winter.

Creating a window garden is easy—you need only to extend the existing sill, and then mount, on the window frame, glass shelves, brackets (if you want them), and lengths of wire (for training vines).  

In my window garden, I paint horticultural portraits to emphasize the seasons. Want to take a look? In this slide show, I'll show you the many different window gardens I've created in my house. 

Left: It’s no trouble to outfit a bay window with glass shelves and brackets. Extending the sill, however, will likely require the skill of a carpenter. For the bay window in my library (pictured), sheets of heavy plywood were used to form a broad surface for plants. This window in January affords copious quarters for geraniums of all kinds, pansies, amaryllis, blue hydrangeas, and vines. On the brackets are rose-scented geraniums. 

THE SILL

If an ordinary window is to become a “Still Life with Plants,” it must first be outfitted for a multi-level display of pots. The sill is the most logical place to start.

Most windowsills are pathetically narrow. The simplest answer to a narrow sill is a foot-wide board or wooden shelf, fastened on a level with the sill as an extension. Paint or stain the board to match your window’s existing trim.

Or you can use an attractive piece of furniture that matches the height of the existing sill—for the window pictured here, a bookcase makes a broad surface for plants.

GLASS SHELVES

For me, a garden confined to the windowsill alone feels inadequate—a real window garden must be a complete horticultural portrait. Consequently, vertical elements are necessary to generate eye movement. And here, gleaming glass shelves come to the rescue.

Three shelves are generally adequate for the average window.  Align one shelf with the latch ledge above the windowsill, and another at the midway point between the two. Position the third shelf at an equal distance above the latch ledge.

I should probably mention that heavy, tempered glass is very expensive—often $100.00 per shelf. But you can ask your glass cutter to make shelves from half-inch-thick salvage glass. Such shelves can be had for about $10.00 each, and non-tempered glass (which I use) is fine.

Most of my shelves are 10-inches deep. They are held in place with 10-inch scrolled shelf supports.

You can find both new and salvage glass from your local glass-cutting shop. Shelf supports are available at any hardware store.    

BRACKETS

Mounted to the window frame, brackets make useful accessories for holding trailing or spreading plants which require a "perch" of some sort. I favor old, cast-iron kerosene lamp holders to support my holiday cacti, cascading petunias, and sprawling scented geraniums. (I buy my lamp brackets on Ebay!)

CHANGING WITH THE SEASONS

One very pleasant aspect of a window garden is that it can be redesigned on a whim. I tend to change mine with the seasons, or whenever I want the window to feature a particular theme.

For Thanksgiving one year, I composed the garden in my upstairs bathroom almost exclusively with plants from East Africa. These included standard, miniature and trailing Saintpaulias, which adorned the sill and shelves. Tolmiea menziesii (left), the fascinating “piggyback plant,” and a pink double impatiens (right), survey the world from brackets. 

FRAMING WITH VINES

The window garden, like any artwork, deserves a suitable frame. Here, I threaded a length of string or wire through 2-inch staples attached to three sides of the window trim. The wire serves as a guide for the long strands of philodendron.

DECEMBER WINDOW GARDEN

In December, the window garden is holiday-themed, with red poinsettias, narcissi in a bowl, and pink and rose cyclamens.

In snow-cloaked February, the window garden offers a preview of spring. This is when fragrant hyacinths make their appearance in a setting that includes miniature roses, azaleas, and crocus. (I plant hyacinth, crocus and other Dutch bulbs in early October for February bloom—here's my guide about How to Force Bulbs.)

If you have curtains in your window, and you can’t bear to remove them for the enjoyment of vines, consider these hangings as a frame for your garden in the house.

Here, I made a windowsill from foot-wide boards, that I stained to match the existing trim, and that I then cut with a jigsaw to fit the bay. Pink hydrangeas, a white petunia, African violets, dwarf geraniums, and fragrant Jasminum polyanthum flourish in the flood of winter sunshine this south-facing exposure admits.

A window garden is neither expensive nor difficult to make, but the beauty it provides a room—especially in winter—is incalculable. 

Kevin Lee Jacobs blogs at A Garden for the House. He was introduced to gardening when he was no taller than a delphinium. Today, his home in upstate New York features formal rose gardens outdoors and lavish window gardens indoors.