Spices, fresh herbs, red meat, cheese. These costly ingredients have proven to be the biggest challenges for chefs taking on our Frugal Foodie challenge. In December, when we asked Grille at Morrison House chef Dennis Marron to whip up a brunch for six for less than $20, he offered some cost-saving advice: Grow your own herbs.

It makes sense. Even a small windowsill garden offers a bounty of flavor for far less than what you’ll spend at the supermarket—a small package of herbs costs $3 to $5. So when I heard that Washington National Cathedral was hosting its annual Flower Mart, I turned Marron’s challenge back on him. Including plants and pots, could we put together a cook’s garden on my small patio for less than $40?

What $38.72 buys you.

We meet at the cathedral, dotted with tents and overrun with children and gardening enthusiasts. As we wander the stands, we talk about must-have herbs. Chives, parsley, and rosemary top Marron’s list, though he warns that parsley can be difficult to grow.

We stop at a stand run by the Four Seasons Gardening Club, a local group selling several varieties of basil and mint as well as chives, parsley, and rosemary. With plants priced at $3 each, the Flower Mart isn’t the most economical shopping spot—at most nurseries, potted herbs sell for about $2—but we conceded the extra dollar in the name of charity (the event raises funds for the cathedral grounds).

Marron and the gardening-club gals debate which plants would best be given my lack of a green thumb. He decides we’ll plant chives, parsley, rosemary, basil, the slightly spicier globe basil, Kentucky mint, and orange mint (grand total: $21). I get explicit instructions on what to keep separate: the mint, which can overtake everything else, and the basil, which needs more room to grow. Marron says the chives will grow rapidly, so I shouldn’t worry about cutting back the stalks. The other herbs, however, will need a little time to get going. With that, I head to the hardware store to pick up a few planters.

The remainder of my gardening budget goes toward four plastic planters—one long rectangle and three small round pots. They’re not very pretty, but at a total of $17.72, they keep me on budget. And thankfully, I still have quite a bit of Miracle-Gro potting soil stashed away from my last gardening attempt. Back at home, I plant my lot and cross my fingers in the hopes that I might have unearthed some latent gardening skill—and future Frugal Foodies might receive an herbal boon.

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