Fill your window boxes with herbs such as mint, thyme or oregano. Create unique ideas for herb window boxes by choosing miniature herbs. Add color with contrasting or variegated foliage. Make the most out of the space by growing more than one type of plant in a window box. The exception to this rule would be a rampant grower such as mint, which would quickly crowd other herb plants out.
Mint is a natural choice for herb window boxes. In the garden, mint can be a thug, crowding out choice plants. Mint spreads quickly through underground runners. When mint is grown in a window box, those runners are contained. As the mint begins to creep out of the window box looking for a new place to root, simply cut the plant back.
Mint grown in a window box may not survive the winter depending on how harsh the weather is. Move the window box into an unheated, protected spot for the winter if you wish to keep it alive but dormant. An alternative is to place the window box indoors in a sunny window.
There are at least 16 varieties of mint to choose from, including candy mint, curly mint, lemon mint, apple mint, peppermint, black stem peppermint, spearmint, orange mint, banana mint and chocolate mint.
Thyme is a tough plant, often used in walkway cracks. Foot traffic doesn't seem to bother this herb. Adding thyme makes perfect sense for an herb window box. Plant it between larger herb plants such as basil, rosemary or lavender. The thyme will form a thick mat, essentially becoming a living mulch. This will help keep your window boxes from drying out as easily.
Thyme comes in many forms from full size to miniature. Thyme is also available in more than 100 different varieties, including common thyme, caraway thyme, lemon thyme, orange thyme, winter thyme and silver thyme.
Don't forget oregano in your herb window box. Greek and Italian oregano are the strongest in flavor, but if you want something more compact, look for miniature oregano. Regardless of the variety you choose, keep your oregano plants pruned so they do not become too leggy.
There are many varieties of oregano on the market. You may be tempted to grow oregano from seed, but the best way to choose a plant is to smell it. If the oregano plant is organically grown, feel free to taste it as well.