Grow your culinary herbs indoors this winter for fresh seasonings all year long.
Fall is a time of mixed emotions for me. After the satisfying yet hard work of tending a summer garden, I am ready for a break. But at the same time, the thought of meals without fresh basil, parsley, rosemary, and thyme from my garden looms like a dreary winter’s day. This fall, I decided to fill my kitchen windowsill with a little trough garden of culinary herbs. Now I have a ready supply of my favorite fresh herbs for flavoring dishes, tossing into salads, and garnishing.
A compact window garden is an easy and convenient way to bring a little bit of the garden indoors year-round. For apartment dwellers and others with limited gardening space, a sunny kitchen window is especially valuable. If the sill is wide enough for a heavy container and if it gets four to six hours of bright light a day, it could be a fine home for the right plants.
The herbs won’t grow as rapidly or as large as they might in the garden, but the restrained growth is better in a confined space anyway. You also may want to save some room for a few tender herbs that you would otherwise lose to winter frost.
Attractive containers to suit any decor are available in garden centers, home decorating stores, and mail-order catalogs. Terra-cotta, wood, ceramic, metal, or plastic containers will all do the job nicely.
Soak unglazed terra-cotta, untreated wood, or other porous containers in water first so they won’t pull moisture from the potting soil when you plant. In dry climates, where the soil dries out quickly, you might be better off with nonporous containers such as plastic or metal.
The size and shape of the container will probably be dictated by the dimensions of the windowsill, but in general, the larger the container, the better. A larger container will allow you to grow more plants and give roots more room to grow. It will also be easier to care for because the soil won’t dry out as quickly.
The container you select must have plenty of drainage holes; chronically soggy soil can lead to root rot, especially in culinary herbs of Mediterranean origin. Resist the temptation to place gravel, small stones, or shards of clay pots in the bottom of the container. They just take up space without helping drainage; in fact, they hinder it.
The clay trough pictured has adequate drainage holes but didn’t come with a tray to catch the excess water because it was designed for use outdoors. I liked the container so much that I bought it anyway and planned to just move it to the sink or tub for watering. I soon found, however, that after I had filled it with potting medium and plants, it was quite heavy and very awkward to move. Now the container sits on four small wooden blocks an inch high, which allow me to slide a shallow tray underneath to catch any runoff.
Choose a prepared fast-draining potting soil or soilless potting medium. You can also mix your own using equal volumes of compost, peat moss, and coarse vermiculite, all of which hold moisture, and perlite, which speeds drainage. Don’t use soil from your garden because it compacts too readily and holds water too long for container gardening. Moisten the potting mix before filling the container. A little may fall out the drainage holes, but the rest will stay in place after it settles.
Because the potting medium in container gardens can dry out quickly, water-absorbing polymer granules can be particularly useful. Mixed into potting soil, they absorb and store water and then slowly release the water when the soil becomes dry. Polymers are available at most garden centers and by mail order. I used 2 tablespoons of the crystals for my container, which measures 81/2 inches wide by 24 inches long by 8 inches deep. The crystals expand significantly when moistened, so moisten both the soil and polymers in a large container to allow the polymers to expand before filling your garden container.
Many herbs grow well in containers and respond favorably to the constant snipping that you’ll be doing when you harvest them. Herbs that would otherwise grow large in a garden can stay manageable in containers if they’re clipped often. Mediterranean herbs such as thyme, rosemary, sage, parsley, oregano, basil, marjoram, and chives will thrive if they get enough light, while shrubby pineapple sage, fast-growing tarragon, rangy dill and chervil, and the invasive mints are best grown outdoors or in separate pots inside. Select herbs with similar cultural requirements, or plant the entire trough with one favorite plant that you use all of the time.
For my own planter, I chose one plant each of basil, thyme, parsley, rosemary, oregano, and chives. I either dug extra plants from my garden or purchased them in 21/2-inch pots from a local nursery. Garden plants often have more highly developed root systems than small nursery stock, so be prepared to give them plenty of room or root-prune them. Knock any potted plants out of their containers, resolutely loosen the root ball with your fingers, and position them in the container, along with any plants you have dug from the garden. Fill in around the plants with potting mix to within an inch of the top of the container, tamping the soil firmly around the plants. Water them well. If your container is fairly deep with room for the roots to spread downward, you can include more plants than if the container is shallow.
Container gardens require daily attention but not necessarily daily watering. I follow the finger test: when the top inch or so of soil is dry, I water thoroughly until water comes out of the drainage holes. Right now, I’m watering about every other day, but as we head into winter and the days become really short, I’ll water less often.
Unlike plants in the ground, container plants are totally reliant on their caretaker to supply the necessary nutrients. I apply a half-strength solution of liquid fertilizer about every two weeks instead of water. You can also use fish emulsion. From December through February, I do not fertilize, as the plants are not photosynthesizing as actively as they do when the days are longer. I also turn my container every week or two so the plants will grow more uniformly.
Soon your kitchen window will provide a little glimpse of summer while the winter winds howl.
Audrey Scano, an assistant editor of The Herb Companion, has windowsills overflowing with herbs. She lives with her family in Loveland, Colorado.