The number of flowers that start with the letter "J'' is relatively small when compared to the vast amount of flowers in the world. The List of Flowers website, for instance, provides the name of nearly 3,000 flowers, but only 18 of them start with a J. Many of the names of these flowers have Greek or Latin origins and are not easy to remember, which is why a list by alphabet can come in handy.

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Jasmine produces a pleasant fragrance.

Justicia

Justicia is a flower that is part of the Acanthaceae family. Also known as the shrimp plant, false hop and shrimp bush, Justicia is native to Mexico and often appears in tropical and subtropical gardens. It grows in clumps of stems and blooms almost continuously. Its leaves are oval, light green and 2 to 3 inches long. It does best in full to partial sun and thrives best in well-drained soil. Justicia was named after Scottish horticulturist James Justice. Its colors include purple and yellow.

Jonquil

Jonquil is a flower that is considered the most fragrant of all the Narcissus species. The Narcissus species are collectively known as daffodils. It is native to Spain and Portugal, and blooms in March and April. It has slender stems that are approximately 16 inches tall. Each stem bears two to six yellow blossoms that are bright in color and approximately the size of a quarter. Its cups are tiny and about one-quarter the size of the petals. Jonquils thrive best in full sun, although they will also bloom in partially shaded areas. They require little care until they bloom and are divided.

Jasmine

Jasmine is a popular flower around the world and is part of the genus of shrubs and vines in the Oleaceae family. It is native to tropical and warm regions of the world and is best known for its unique fragrance. There are approximately 200 species of Jasmine. Jasmine blooms in either spring or summer, approximately six months after planting. It releases its fragrance after the sun has set and the moon is approaching its full stage. It is primarily a climbing vine or bushy shrub. Its flowers are waxy-white in color and its leaves are round and shiny. Its shrubs reach heights of 10 to 14 feet. The flowers are around 1 inch in size.