Hot peppers add both color and flavor to many different dishes. They come in multiple sizes, colors and levels of spiciness: everything from fairly mild to ultra-hot. Choose the one that best suits your needs or grow several different kinds to provide yourself with some choices when it comes time to cook. They are hardy in U.S. Department of Agriculture hardiness zones 7 through 11, but are almost always grown as annuals, not perennials.

Peppers and chilli peppers, Chile, (Close-up)
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Hot peppers come in a variety of colors, shapes and sizes.

The Scoville Scale

The Scoville scale measures how hot a pepper is in Scoville Heat Units, or SHU. The higher the number, the hotter the pepper. Ratings start at zero; there is no cap on the upper end as growers continually try to create ever-hotter peppers. Peppers on the low end of the scale, from 0 to 2,500, are considered mild. Next are the medium peppers, ranging from 2,500 to 30,000. Peppers with 30,000 to 100,000 SHU are classified as truly hot peppers, while those rated at 100,000 or more are considered extra hot. The Scoville rating is related to the levels of capsaicin in pepper; when rated, peppers are assigned an SHU range because the same plant will produce hotter fruit under harsher growing conditions. Different cultivars of the same species may also produce different amounts of heat.

Mild Peppers

Mildly hot peppers find their way into many dishes, adding zest but very little heat. Some common types of these are:

Anaheim

These peppers, Capsicum annuum 'Anaheim', prefer full sun and rich, well-drained soil. They grow on plants that get up to 2 feet tall and as much as 18 inches wide. The peppers are ready for harvest from 74 to 80 days after planting. Mature fruit is about 7 inches long and 2 inches wide and may be harvested and used while still dark green. When fully ripe, they turn a deep red.

Pepperoncini

Popular on pizza and in many Italian dishes, pepperoncini, Capsicum annuum 'Pepperoncini', are spicy, but mild, and are often pickled. These peppers are red when ripe, grow between 2 and 5 inches long and need 110 days to reach maturity. Pepperoncini require warm, well-drained soil and full sunlight.

Medium-hot Peppers

Medium peppers have some heat to them, but are still relatively mild to the pepper-loving palate. Gardeners who've never grown peppers before may want to include some of these in the garden.

Cascabel Cherry

These are tiny peppers, averaging about an inch or less across. They may be round or slightly flattened looking and are typically medium-hot. Cherry peppers come in more than one variety, but the Cascabel, Capsicum annuum 'Cascabel', is one of the better known types. The plants get up to 3 feet tall, need well-drained soil and full sun. These peppers take 80 to 100 days to mature.

Jalapeno

One of the most common peppers in the United States, Jalapenos, Capsicum annuum 'Jalapeno', peppers are about 3 inches long and 1.5 inches in diameter. They are often harvested while they are still green, but if left to mature fully they become bright red. Jalapeno pepper plants grow up to 4 feet tall and need full sunlight and rich, well-drained soil; they mature in 72 days.

Hot Peppers

These peppers are popular in many spicy dishes and can be used either fresh or dried. They are perfect for the gardener who wants to cook truly hot foods.

Tabasco

to about 3 feet tall in well-drained, fertile soil. They require full sun and mature in 80 days. The peppers are any color from yellowish-green to red or orange and are typically about 1.5 to 2 inches long.

Banana Peppers

Banana peppers, Capsicum annuum 'Banana', can be anything from sweet and mild to hot. The hot ones are sometimes called Hungarian wax peppers. Since they all look the same, be sure to label your plants if you grow more than one variety of these. The 2-foot-tall plants do best in full sun and fertile, well-drained soil. These 6-inch peppers are green when small, turning to yellow as they mature and finally turning bright red, at maturity of about 75 days.

Extra Hot Peppers

These peppers may be too hot for many people, but they're certainly worth adding to your garden if you want to give them a try.

Tiny Samoa

A very small pepper that is no more than 3/4 of an inch long when mature, these very hot peppers turn red when they mature at 70 to 80 days after planting. Tiny Samoas, Capsicum annuum 'Tiny Samoa' need full sun and well-drained soil, but at only 12 inches tall these they can also be potted and grown as a house plant.

Habanero

The Habanero, Capsicum chinense 'Habanero', is one of the hottest peppers that is readily available to grow in your garden. A little goes a long way with the Habanero pepper. The small fruit is shaped something like a lantern and gets about an inch or two in length. It is dark green when immature and becomes orange as it ripens. They grow well in full sunlight and rich, well-drained soil and the peppers mature in about 95 days. The plants get from 2 to 3 feet tall.