In early spring, before my basil has grown big enough to harvest, I usually buy them as “living herbs” in the supermarket. You’ve seen them in the produce aisle: the fresh herbs in little pots with their roots still attached.
The logic behind these living herbs is that they stay fresher longer than the cut sprigs sold in clamshells. I’ll sometimes keep mine on the windowsill for up to three weeks, pinching off a stem here and there while I’m cooking. For most people, however, the herbs have already keeled over by this point. Living herbs are produced with the ordinary consumer in mind, so they aren’t meant to last more than a week or two.
So maybe it’s the gardener in me who can’t resist “saving” an herb. Since I continually pinch off the basil each week, it keeps growing and growing until it’s obviously unhappy in its plastic pot.
Rather than composting the basil, I usually try to extend its life by transplanting it in the garden. I can raise several new basil plants this way and get more bang for the buck out of something that’s supposed to be “disposable.”
Before you stick a supermarket herb in the soil, here are five things you should know.
1. Supermarket herbs should be transplanted soon after purchase.
To increase the chances of your herb surviving, it should be moved into a larger pot or into the ground the week it’s brought home. Supermarkets aren’t watering or fertilizing these herbs the way a nursery might while they’re sitting on the shelves. They’re typically grown in a sterile potting medium that’s devoid of nutrients, so you’ll want to transplant the herbs into richly amended soil and give them plenty of sunshine to help them thrive.
2. Supermarket herbs are planted intensively.
Since they go to market as seedlings, they’re seeded thickly and grown close together so it looks like you’re getting a full-grown plant. The seedlings compete for space and light as they grow, often struggling as their roots become more rootbound.
3. Supermarket herbs should be divided before transplanting.
To keep your plants healthy, gently prod the root ball apart with your hands or cut them with a clean pair of shears. I usually leave two to three seedlings per transplant, and remove the weaker ones as the plant matures.
4. Thin the divisions as needed.
Remove any tiny seedlings by snipping them off at the base of the stems. These seedlings will never be able to survive in the shade of their taller neighbors. But don’t throw them out — use them in a salad as microgreens!
5. Bury the stems of basil seedlings and water well.
Just like you do with tomatoes, plant the basil up to its lowest set of leaves (even removing the last set if it’s starting to yellow) to encourage roots to form along the stem. Keep the basil well-watered (but not water-logged) to reduce the effects of transplant shock.
It may take a few weeks for the basil to bounce back, but once it does, there’s no reason it couldn’t look like this by the end of the season! (And yes, this three-foot-tall basil started from a supermarket herb just months before!)