Lamiaceae

Also known as the Mint family.

Herbs with square stems, usually aromatic.

  1. Flowers perfect, bilaterally symmetrical. Sepals 5, fused. Petals 5, fused, 2-lobed upper lip and 3-lobed lower lip. Stamens 2 or 4, fused to petal. Pistil compound, ovary superior, carpels 2, but deeply lobed.
  2. Fruit 4 nutlets.
  3. Leaves simple, opposite or whorled.
  4. About 200 genera, 3200 species, cosmopolitan

Most Lamiaceae contain fragrant oils, and many are used as herbs or flavorings, including Mentha (mint), Salvia (sage), Rosmarinus (rosemary),Thymus (thyme), Marrubium (horehound), Nepeta (catnip), Satureja (savoury), Origanum (oregano), Majorana (sweet marjoram), Ocimum (sweet basil).

Vegetative Features

There are some features that the members of this family share that help you to identify them even if they are not flowering: square stems, opposite leaves. The picture below of Coleus demonstrates the opposite leaf arrangement. Leaves are in pairs along the stem.
Coleus Plant

Coleus Plant

A square stem is another diagnostic feature of this family.
Coleus, square stem

Coleus, square stem

Another example of the square stem found in this family.
Square stem

Square stem

Salvia (sage). There are many different species of sage. Some used for spice. The one pictured here is a common ornamental plant.
Sage Plant

Sage Plant

Close up of the flowers of the sage plant.
Sage Flower

Sage Flower

A longitudinal section through a flower.
Sage Flower, Longitudinal Section

Sage Flower, Longitudinal Section

A look at an isolated stamen.
Isolated Stamen of the Sage Flower

Isolated Stamen of the Sage Flower

Nutlets:
View of Nutlets

View of Nutlets

Other Members of Lamiaceae

Mentha – spearmint.
Spearmint

Spearmint

If you look closely you can see some nutlets!
Close Up, Illustrating Nutlets

Close Up, Illustrating Nutlets

Stachys – lamb’s ears . This plant has many fine trichomes which are soft to the touch (hence the common name).
Stachys

Stachys

Another photo of lamb’s ear.
Stachys Inflorescence

Stachys Inflorescence

Ajuga – bugleweed. Ajuga has been used in folk medicine for healing skin wounds. Tannins (astringents) are found in the leaves. the plant has also been used as a source of black dye. It also makes a very handsome ground cover. Gardeners often use it as a border plant.
Ajuga

Ajuga

A good look at a flower! The two upper petals are very small. the lower petal is lobed.
Stachys, Close up

Ajuga, Close up

Lavendula – lavender. This plant has a long history of use as a fragrance.The flowers are sold whole or as an oil. It is most famous for its calming effect. It has also been recommended by herbalists to relieve intestinal gas.
Lavender Plant

Lavender Plant

Thymus – thyme (with friend). Thyme has had a long history of medicinal use as cough suppresant. It is a common herb used in a wide variety of dishes.
Thyme Plant

Thyme Plant

Prunella – heal-all. It is somewhat of a mystery how this plant earned its common name. There is little evidence that suggests it played a major role as a medicine. It was used as an astringent and in a throat gargle.
Prunella

Prunella

Rosmarinus officinalis – Rosemary. A favourite culinary herb, Rosemary has many uses. Diluted Rosemary oil is a taken to relieve intestinal gas. In ancient Greece it was believed to improve memory so students wore it in their hair while studying. It became a symbol of remembrance and sprigs of rosemary were often placed with the dead to ensure that the dead would not be forgotten.
Rosmarinus officinalis

Rosmarinus officinalis

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