The burn comes from capsaicin, a compound that is found in all parts of a chile pepper's fruit, but is particularly concentrated in the seeds and ribs. The more capsaicin, the hotter the pepper. What distinguishes mild heat from maniacal is the variety's relative position on the Scoville Heat Unit (SHU) scale. The SHU rating for each variety is determined by professional testers who sample a pepper and record its heat level. The sample is then diluted with sugars until heat is no longer perceptible to the testers. The amount of dilution determines the pepper's SHU level. A sweet bell pepper, with no capsaicin, is the baseline at zero SHU. Although the scale is an excellent guide, it is subjective, because an individual pepper's heat is influenced by climate, weather, and growing conditions, as well as the taster's sensitivity.
Discover your inner fire-eater by growing the hot pepper varieties that fit your culinary tastes and pique your gardening interest. Here are some of our favorites. Give them a try.
There are many different jalapeño varieties, but hybrid 'Señorita' is special because it has all the flavor of a jalapeño with just a hint of the heat. Most jalapeños hit 5,500 on the SHU scale, but 'Señorita' is a mere 300 to 400 SHU. Ben Maniscalco, founder of Benito's Hot Sauce in Hyde Park, Vermont, says all jalapeños are terrific choices for northern growers. "They do just fine in New England," says Maniscalco, "because they typically have an early to midlength growing season." 'Señorita' matures in about 60 days.
Poblano peppers are relatively mild (about 1,000 to 2,000 SHU) and measure 3 to 5 inches long. They are often harvested when green, but mature to a beautiful, deep red. Known as anchos when dried, these popular Mexican chiles are a common ingredient in mole sauce and chiles rellenos, peppers stuffed with cheese and fried in batter. Joe Arditi, president of Pepper Joe's Seeds in Myrtle Beach, South Carolina, favors poblano peppers for their superior taste and form. "They're really the ideal shape for stuffing, although they're also great to eat raw in salads or with dip because they are so mild."
With the same SHU rating as the poblano, the chilaca is sometimes called chile negro because of its dark brown or purple coloration when mature. It is one of the pasilla chile peppers, another type that is commonly used in Mexican mole sauces. "Pasilla means 'little raisin' in Spanish," says Lee James, grower and owner of Tierra Vegetables in Windsor, California. "Pasilla dries blackish and is wrinkled like a raisin." The fragrance is much like that of a raisin, and the smoky flavor has hints of grape. Common in Mexico, they are more difficult to find north of the border.
'Anaheim' is the best known of the New Mexico chile peppers, the fruits of which grow 6 to 8 inches long and can be used either green or red—the redder, the hotter. 'Anaheim' peppers have heavy skin and thick flesh that is particularly suited to roasting and grilling. Because their maturation rate ranges from 70 to 90 days, these peppers perform best where the growing season is a bit longer. The ripe, red fruits are often strung up to dry in a long chain called a ristra. New Mexico peppers range from 500 to 7,000 SHU.
It's easy to see where this heirloom pepper got its name. With long, tapered orange fruits, 'Bulgarian Carrot' might fool one into thinking it's sweet, but at 5,000 SHU, that is not the case. The highly productive plants mature in 75 days, and since they reach only 20 inches tall, they're perfect for container growing. The bright orange color lends itself nicely to fresh salsas and chutneys. Called shipkas in Bulgaria, where the variety originated, these peppers are both beautiful and mouth-warming.
This hybrid cherry pepper matures green in a mere 65 days (80 days to red), making it a great choice for northern and southern gardeners alike. The seeds of 'Big Bomb' are easy to remove, and its small, rounded shape and thick walls make it ideal for stuffing. It looks and tastes great in a pickle jar. About 5,000 SHU.
'Hungarian Hot Wax'
A reliable hot pepper even for northern climes, 'Hungarian Hot Wax' is a prolific producer of elongated, tapered pods about 5 to 6 inches in length. Popular for pickling and frying, and with SHU ratings ranging between 5,000 and 10,000, this pepper has slight sweet notes right along with the heat. It's also called a hot banana pepper because of its yellow to orange coloration that eventually ripens to a full red.
"Serranos are one of my favorite varieties for making salsa," says Craig Andersen, Ph.D., horticulture extension specialist with the University of Arkansas. "They have heat along with a unique floral fragrance that smells like violets to me." Plus, they have thin skin, so there's no need to peel before use. Serranos weigh in at about 25,000 SHU; expect a kick, but also a unique flavor. Thin and pointy, they mature from green to yellow, orange or red. Their thick flesh doesn't dry well; use these fireballs while fresh and crisp.
A hybrid with increased disease resistance, 'Big Red' cayenne peppers can grow to a whopping 10 to 12 inches in length. Maturing to deep red, cayenne peppers are often dried and pulverized, then sold as hot pepper flakes and cayenne powder. Used in chili and other spicy dishes, cayennes boast a punch (30,000 to 50,000 SHU). "These peppers are fantastic for drying. I also roast them in the oven and use them on pizza and sandwiches," says Arditi. Another plus: 'Big Red' is more resistant to fruit rot than other cayenne varieties.
'Indian Finger Hot' (India Jwala)
This 4-inch-long, very slender fruit with wrinkled skin is the most popular hot pepper in India, where it flavors an array of spicy dishes. It is a superhot (50,000 to 100,000 SHU), taste-bud-searing pepper that may floor even those who claim asbestos palates. As with all hot peppers, wise cooks wear rubber gloves when handling.
An heirloom variety, 'Thai Dragon' is a 3-inch-long pepper that's used in Asian cuisines. Exuding incredible heat (50,000 to 100,000 SHU), this pepper has excellent flavor if you can make it past the burn. One plant can produce as many as 200 peppers. Because the fruits ripen all at once, they are easily dried by pulling up the entire plant and hanging it upside down in a warm, dry place. The dried pods can then be harvested as needed.
"Chiltepins (also known as wild bird peppers) are the original wild chile pepper from which we've derived thousands of different chile varieties," says Danise Coon, program director of the Chile Pepper Institute at New Mexico State University. Chiltepins still grow wild in Arizona and Texas. These beadlike peppers have a lingering, super-intense heat (75,000 SHU).
This tiny, fiery pepper's Thai name is translated into English as "mouse dropping pepper," and it's among the hottest chiles (100,000 to 250,000 SHU). Found commonly in Thai and Cambodian cuisine, bird's eye chile peppers lend a powerful heat and a unique flavor. Anecdotally, one should be able to eat a Thai dish made with the same number of bird's eye peppers as one's age in years.
Scotch bonnets belong to the same species as habaneros (Capsicum chinense) and pack an equally mouth-scorching punch. "They don't have as long a growing season as habaneros, though, which need it to be hot all the time, so we have better luck with them during our frequent foggy nights," notes Lee James from California. Scotch bonnets are among the hottest peppers in the world, ranging between 100,000 and 300,000 SHU, and feature in Jamaican cooking and hot sauce.
The hottest pepper on the planet, 'Bhut Jolokia' measures a breath-robbing 1,001,304 SHU! Hailing from India, the "ghost chile" is tough to grow. "'Bhut Jolokia' peppers are stubborn and not for the novice grower," says Coon. "They are an interspecific hybrid—meaning they are a cross between two different species, which doesn't happen very often. That's what makes this one unique and probably contributes to its crazy hotness." Joe Arditi says, "This is the pepper than can send you to the emergency room."
All hot peppers need well-drained soil high in organic matter—and the warmer the soil, the better. Be sure the soil is at least 60°F (typically 7 to 10 days after the last-frost date in many areas of the country) before planting. Gardeners in the extreme South and parts of the Southwest can grow peppers year-round. Maintain a soil pH between 6.2 and 6.5 for maximum nutrient absorption. And give them room: Crowding decreases air circulation and increases the chance of disease. Mulch peppers with untreated grass clippings, straw, or finished compost to reduce weeding and keep the soil moist. Dryness can result in blossom-end rot; though chile peppers thrive in hot temperatures, consistent soil moisture is key. Fruit set is best when temperatures are between 70° and 85°F. If they top 80°F at night or 90°F during the day, the flowers may abort. Bud or flower drop can also be caused by stressors like drought or wind, but the problem usually goes away when the stressors are no longer present.
More information & sources for pepper seeds:
Pepper Joe's Hot Peppers: pepperjoe.com
New Mexico State University's Chile Pepper Institute: chilepepperinstitute.org
Baker Creek Heirloom Seeds, 417-924-8917, rareseeds.com
W. Atlee Burpee & Co., 800-333-5808, burpee.com
Reimer Seeds, reimerseeds.com