Classification/identification/differentiation of capsicum plants can be done on the basis of the following characteristics:
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Tabasco (C. frutescens)
According to Floridata, “C. frutescens and C. chinense are quite difficult to distinguish, and many authorities lump them as one species, C. frutescens, which is characterized by having two or more purple or greenish white flowers at each node. […] C. frutescens (including C. chinense) probably originated in the Amazon basin of South America.”
Wikipedia has the following to say: “the tabasco plant has a typical bushy growth […]. The tapered fruits, around 4 cm long, are initially pale yellowish-green and turn yellow and orange before ripening to bright red. Tabascos rate from 30,000 to 50,000 on the Scoville scale of heat levels, and are the only variety of chili pepper whose fruits are “juicy”; i.e., they are not dry on the inside. Unlike most chilis, tabasco fruits grow up, rather than hanging down from their stems.“
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Rocoto (C. pubescens)
“The rocoto (from Quechua ruqutu), or locoto (from Aymara luqutu) (Capsicum pubescens) is a medium sized round chili pepper common in Peru, Bolivia, northern Chile, northern Argentina, and Ecuador.” – Wikipedia
“C. pubescens is the only pepper species with black seeds (all the others are straw colored). The stems and leaves are slightly fuzzy. This is the most distinctive of all the cultivated peppers. The fruits look like small apples and have very thick fleshy walls. They are extremely piquant.” – Floridata
Floridata also mentions that rocotos do not flower until the days shorten to 12 hours of daylight, and won’t flower if temperatures are much above 27º C.
According to Gardening.eu, rocotos “tend to develop like erect small trees. This plant in the summer assumes a white colouring; it is large in size and can reach 3 m high. It keeps its leaves in the winter. The rocoto develops like a shrub.“
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Chili pepper plant identification – pods
First, a disclaimer: the characteristics described below are generalizations – there are always exceptions; hence, they must be taken in connection with other identifying traits. The more distinguishing characteristics are highlighted. Also, I am focusing here on the five main species of the Capsicum genus; there are many others, though not as common/popular.
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SPECIES |
C. annuum
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C. baccatum
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C. chinense
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C. frutescens
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C. pubescens
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| Calyx (junction of pod with stem): | without constriction at junction with stem (though sometimes irregularly wrinkled) | without constriction at junction with stem (though sometimes irregularly wrinkled) | usually with constriction at junction with stem | without constriction at junction with stem (though often irregularly wrinkled) | without constriction at junction with stem |
| Calyx teeth: | often prolonged into short teeth | prolonged into prominent teeth | not prolonged into teeth | usually not prolonged into teeth | prolonged into teeth |
| Fruit: | usually erect and become pendant as they mature | pointy and erect | usually pear- or apple-shaped | ||
| Fruit flesh: | usually firm (soft in certain varieties) | firm | firm | often soft | firm |
| Seeds: | straw-colored | straw-colored | straw-colored | straw-colored | dark in color |
| Examples: |  |
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Chili pepper plant identification – flowers
First, a disclaimer: the characteristics described below are generalizations – there are always exceptions; hence, they must be taken in connection with other identifying traits. The more distinguishing characteristics are highlighted. Also, I am focusing here on the five main species of the Capsicum genus; there are many others, though not as common/popular.
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SPECIES |
C. annuum | C. baccatum | C. chinense | C. frutescens | C. pubescens |
| Pedicels (flower stems) at each node: | solitary (occasionally in clusters) | solitary | two or more (occasionally solitary) | solitary (occasionally in clusters) | solitary |
| Pedicels (flower stems) during blossoming: | usually declining | erect or declining | erect or declining | erect but flowers nodding | erect but flowers nodding |
| Corolla (petal) color: | milky/creamy-white (occasionally purple), without spots | white or greenish-white, with distinctive scattered dark green, brown or yellow spots at base | greenish-white (occasionally milky/creamy-white or purple), without spots | greenish-white, without spots | purple (occasionally with white margins and/or white base), without spots |
| Corolla (petal) shape: | usually straight | usually slightly rolled backward at the edge | usually straight | often slightly rolled backward at the edge | usually straight |
| Anther (pollen sack) color: | purple and white | yellow or tan | purple | purple | purple and white |
| Examples: |   |
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purple and white
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Flower and fruit development
‘The key to the formation of fruit is nighttime temperature, which ideally should be between 18 and 27 °C. Fruit set is enhanced by increased sunlight, however fruit will not set when night temperatures are above 30 °C.’ – Chile Pepper Institute
The Chili Pepper Project 