I'm a prolific home cook and like any maker of food—I love cooking with fresh herbs. One way to access fresh herbs all the time is to grow them yourself. However, if you're like me—living in the city without a backyard—then you'll likely have to resort to windowsills and well-lit countertops.
At any given time I may have over a dozen different varieties proliferating in my windows—mint, lemon balm, oregano, sage, santolina, bay, curry—you name it, I like to grow it (and cook with it)! But sometimes I run into problems—pesky aphids might take down a plant within days—or more likely—I just use up all my herbs!
Over the past several years, however, I've seen more supermarkets begin carrying herbs. No—not the pre-cut herbs in air-tight containers, but fully-grown ones with roots contained in plastic black planters and enveloped in clear film bags. Is this a response to more folks like me wanting fresh herbs? No doubt. But it's also a response to the rise in hydroponics, which is a method of growing plants without soil, which is how these herbs were likely grown.
If you've ever tried to continue to "grow" these $1.99 supermarket plants in your home, you may have been met with some friction for a couple reasons. First and foremost, the plants were raised in a hydroponic environment. This means that their roots were surrounded by water and fed mineral nutrients. The roots did not "grow up" in soil and are therefore largely unfit for being repot in a soil medium. Secondly, most of the plants you buy in the supermarket have been selected when they are at their optimum growth—largely right before they would flower and set to seed. This basically indicates that they may likely wane shortly thereafter, particularly if they are more sensitive herbs like cilantro or dill.
You'll likely not be able to grow your supermarket herbs in pots with soil like my santolina or Vick's plant to the far left. Plants grown in hydroponic settings often don't develop the root structure that is required to grow in a soil setting.
Now this is not to say they are impossible to grow. As a matter of fact, you'll likely be able to keep them for two maybe three weeks after their purchase date—far longer than if you purchased the cut varieties. And two or three weeks may be all of what you need to have used them in your cooking. I've found that they survive the best when you give them a similar environment from where they came. Since that wasn't a soil environment—sticking them in pots with a good potting soil—isn't going to suffice. Instead, keep them in their plastic pots and place the plants in deep bowls and add filtered or distilled water to the bowl. Be sure to keep them on a sunny windowsill. A couple days in, change the water to keep the oxygen levels up and add some nutrients—like a diluted seaweed tonic.
I personally like to buy supermarket herbs in the colder months when it's tough to find good herbs in my garden center and I know I'm running low. They are an incredible 'hold-over' solution—but not something for the long-term.
If you wish to grow herbs in soil-based pots in your home—like on a sunny windowsill or in the yard—then I'd highly recommend that you pick up seeds or seedlings from your local garden center or greenhouse. These herbs, unlike the hydroponic varieties, will have the appropriate root structure for growing in a pot. Additionally, you can alternatively embrace hydroponic herb growing in your home, like in the case of Cloud Farms, Amphora vase or other easy-to-assemble hydroponic systems. Or check out new systems, like the LeGrow Smart Garden, which should be hitting the market soon after its successful Kickstarter. I also find growing microgreens—whether in hydroponic or soil-based systems—is a wonderful way to have fairly consistent, self-sustaining access to fresh herbs and greens all year long. 🌿