Choosing and Growing Hot Chili Peppers

  • 01 of 03

    All About Chili Peppers and How Hot is Hot?

    How to Grow Hot Chili Peppers
    Photo: © Marie Iannotti

    Hot peppers have had quite a resurgence in popularity, in recent years. Once the domain of ethnic dishes and asbestos-mouthed show-off, chili peppers and hot sauces are not commonplace everywhere from snack foods to diner booths. And growing hot peppers has become positively competitive

    Hot peppers may have become commonplace, but there doesn't seem to be a consensus on how to spell chili pepper. Chili is the generally accepted form for chili con carne and Chile, with an "E", is the name of a country in South America, but you will find chili, chilli, and chile used interchangeably, to refer to hot peppers. One "L" or 2 seems to depend on your geographic region. For purposes of this article, I will stick with chili.

    Regardless of how you spell it, chili peppers are expected to be hot. However hot is a relative term and one person's scorcher is another person's tease. Thankfully there are dozens of varieties to choose from, which helps make chili peppers popular across the board. They all owe their heritage to a small wild pepper traced back to at least 7,000 BC, in Central and South America.

    Christopher Columbus is credited with giving them the name "pepper"  because its zing reminded him of black pepper, an unrelated species  (Piper nigrum). Someone on one of his ships brought the first chili peppers back to Spain and from there they were eventually dispersed throughout Europe, Southeast Asia, and the Middle East. Some cultures were quicker to incorporate them in their cooking than others.

    Although chili peppers were grown in colonial America, not all the colonies were enamored of them. George Washington and Thomas Jefferson both grew a cayenne variety, but their real popularity was in the Southwest and the area around New Orleans.

    Types of Chili Peppers

    You can't always tell a hot pepper by its name. All peppers are in the genus Capsicum. There are 5 species of Capsicum in cultivation. Most of the commonly grown vanities, like cayenne, jalapenos, and serranos, are Capsicum annuum. Many of the Asian hot peppers, as well as tabasco peppers, are C. Frutescens. Habaneros and Scotch Bonnet are C. chinense.  The fiery 'Aji' peppers, like ' Aji Amarillo', 'Aji Colorado', 'Aji Cristal', belong to C. baccatum. And the wild peppers chiltepíns and chilipiquíns, from the regions around Mexico, are C.  glabriusculum. However they are classified, there's a lot of variety.

    How Hot is Hot?

    It wasn't until 1912 that anyone devised a means for measuring the heat of hot peppers. A pharmacologist named Wilbur L. Scoville came up with a rather ingenious, if imprecise, method. He diluted the oils from various peppers in sweetened water and had volunteers taste it. Scoville measured how diluted a pepper's oil had to be before the testers could not detect any heat. This is known as the Scoville Scale and is used for foods other than chili peppers, like

    The sweet bell pepper came in at zero Scoville heat units (SHU) and set the starting bar. Jalapenos rated 2,500 SHU, which means 2,500 parts of sugar water to 1 part Jalapeno extract.

    For example, a jalapeno rated at 2,500 SHU would be 2,500 parts of sugar water to one part Jalapeno extract. The higher the SHU, the hotter the pepper. Habenero's scored 350,000 SHU.

    Today they use a chromatography machine, which is much more accurate. However, the same type of chili peppers grown under different conditions can vary widely in heat level. (More about that later.) Curious about what is the hottest pepper in the world?

    Continue to 2 of 3 below.
  • 02 of 03

    Categories of Chili Peppers to Grow

    Fatali Pepper Plant
    'Fatali' are a type of habenero pepper with a smoky heat. Photo: © Marie Iannotti

    Common Types of Chili Peppers to Grow

    Besides the botanical classifications I mentioned above, chili peppers are often grouped by their SHUs and by the shape of their fruits. Here are some of the most popular varieties, in order of heat ratings:

    • Anaheim - Long, tapered fruits with moderately thin walls. Medium to mild heat (1,000 - 5,000 SHU)
    • Jalapeno - Short, stubby peppers with a slight taper and thick walls. Medium to mild heat (2,000 - 5,000 SHU)
    • Serrano -  Short and slim with medium thick walls. Medium to high heat (10,000 - 25,000 SHU)
    • Cayenne - Long, thin, curving fruits with thin walls (perfect for drying). Medium to high heat (25,000- 50,000 SHU)
    • Tabasco - Very short and pointy, with thin walls. Medium high heat. (30,000 - 60,000 SHU)
    • Thai - Small and slender, with walls. More heat than flavor. Medium high heat. (50,000 to 100,000 SHU)
    • Habanero - Short, squared fruits with thin walls. High heat. (150,000 - 350,000 SHU)
    • Ghost - Short, squat, slightly tapered fruits with thin walls. Extremely high heat. (1,000,000+ SHU)

    Why Would Anyone Eat Chili Peppers?

    While some chili peppers are merely hot, most also have distinct flavors, from fruity to smoky. In addition to their taste appeal, the heat - and resulting pain - is also thought to stimulate the production of endorphins, which produce a sense of well-being, once the pain wears off. It's a lot like the pleasure of scratching an itch or a runner's high.

    Continue to 3 of 3 below.
  • 03 of 03

    Tips for Growing Truly "Hot" Peppers

    Basket of Hot Peppers
    Photo: © Marie Iannotti

    Growing Chili Peppers with Real Heat

    While your choice of variety will certainly play a big part in how hot the chili peppers that you grow ​turn out to be, there are a few growing conditions that will improve their heat.

    1. Chose varieties with shorter growing seasons. Some hot peppers don't start setting flowers and fruits until days begin to shorten, in the fall. I've had this problem with one of my favorite Habanero types, 'Fatalli'. Peppers with shorter growing season will have time to fully mature and develop their heat.​
    2. Hot air and soil temperatures seem to increase the heat level in peppers. While we can't control the weather, you can cover the soil with black plastic, to trap and increase the soil temperature.​
    3. Grow your plants on the dry side. Don't withhold water totally, but be stingy with it. Allow the plants to remain dry for several days before watering again.​
    4. Go easy on the fertilizer, especially nitrogen fertilizer, but even compost. Along with minimal water, grow your plants on the lean side. I'm not suggesting you stress your pepper plants, but don't pamper them. Get them established in the spring, then let them fend for themselves.​
    5. Don't be afraid to crowd your pepper plants. They will fight all the harder to set fruits.

    Here are the basics and a few more tips for growing hot peppers in your garden.