When Chitra Agrawal returned from a visit to India, she missed the spicy achaars that had livened up her food. She found the Indian relishes sold in the United States to be loaded with salt and preservatives, but she didn't want to increase her carbon footprint by importing ingredients. Instead, she founded BROOKLYN DELHI to meld Indian cooking with local, seasonal produce, turning out small-batch sauces with flavors like rhubarb ginger and gooseberry. Agrawal's tangy, layered Tomato Achaar is her most popular: Critics praise its uncompromising kick. $8.75 for a 6-ounce jar

Raised by sweet potato growers, April McGreger began FARMER'S DAUGHTER in Carrboro, North Carolina, to celebrate southern cooking, so her Sweet Potato Habanero Hot Sauce incorporates North Carolina's state vegetable. Local, organic sweet spuds get combined with peppers grown on crop-rotated fields. The flavors are well matched, says food writer Allston McCrady, with the habaneros lending "a bright, fruity heat tempered by the mellow base of the sweet potato." When seasonal batches run out, fans must wait until the next year for more. $9 for a 10-ounce bottle

"I wanted to bring transparency back to the food system," says Robyn Jasko. Which is why she started HOMESWEET HOMEGROWN in Kutztown, Pennsylvania. Visitors can handpick peppers on her two acres of organic fields, reclaimed from growing genetically modified corn. Scotch bonnet, ghost, and lemon drop chilies all turn into tasty sauces that bring the heat. Jasko's best-selling Punch Drunk variety is inspired by mole, incorporating raw cacao and beer from nearby Victory Brewing Company. Try it in chili and on pasta. $6 for a 5-ounce bottle

The Barrel-Aged Sriracha from SOSU isn't your run-of-the-mill rooster sauce. Organic, preservative-free pepper mash gets aged in old whiskey barrels, lending oaky notes. The thick sauce's fruity, smoky, intense flavor gets enthusiastic reviews. "Three months in a whiskey barrel," writes food critic Marcia Gagliardi, "do good things to sriracha." Sosu repurposes the peppers' leftover skins and seeds as a spice rub. In this year's batch of Srirachup—sriracha meets ketchup—Sosu used unshapely heirloom tomatoes from a local farmer who would have tossed the fruit. $15 for a 9-ounce jar

ALEX'S UGLY SAUCE looked unappetizing to one of Alex Bourgeois's coworkers (hence the name), but the Massachusetts company is founded on beautiful friendships with local growers. Nearby farmers give him their excess peppers, which he turns into "microbatches": single-run, 300-bottle hot sauces that the farmers then sell at their stands. The Original flavor offers a fiery blend of habanero, cayenne, and serrano peppers whose spiciness, Bourgeois says, "starts on the tip of your tongue and then rolls back." $30 for a three-pack of 5-ounce bottles