Tanacetum balsamita COSTMARY (plant)

Costmary, also known as Alecost, Bible Leaf, or Tanacetum balsamita in Latin, is an aromatic perennial plant from the Asteraceae family.
It is grown in gardens for the aroma of its leaves and as an ornamental variety.

This species is native to Western Asia and the Caucasus. It grows to a height of 1 to 1.50 meters. Its foliage consists of green, oval leaves that are deeply lobed with a slightly downy texture. When crushed, the leaves release an aromatic scent evocative of the famous spearmint (chlorophyll) chewing gum.

The plant flowers in late summer, producing small yellow flowers clustered in dense corymbs.
These flowers often attract pollinators such as bees and butterflies, thanks to their subtle fragrance and bright color.

Alecost seeds, contained within the achenes, are tiny and oval, measuring only one millimeter in length.
They have a smooth to slightly wrinkled surface. Their ability to disperse effectively contributes to the natural expansion of the plant in its environment.

- Properties:

A Historical Heritage: From "Chartreuse" to the Gospels

Formerly nicknamed the "Bible Leaf," this robust perennial was the star of monastery gardens.
Its foliage, once used as a natural bookmark to scent religious manuscripts, historically enters into the composition of the famous Chartreuse liqueur.
Choosing a plant from Ethnoplants means reintroducing a fragment of medieval history into your garden, where dried leaves were used to flavor beverages and make herbal teas with balsamic notes.

Culinary Flavors and Traditions

In cooking, costmary offers a "chlorophyll" flavor, subtly minty and balsamic, ideal for enhancing rustic soups, spring salads, or traditional preparations.
Appreciated for centuries for its unique aromatic qualities, it holds a prominent place in herb gardens.

A Natural Repellent and Linen Protector

In the garden, costmary is a valuable ally in biological pest control: its powerful scent acts as a natural repellent against many insects.
By placing a few dried leaves in your cupboards, you will sustainably protect your textiles while delicately scenting your laundry.
Its ground-covering habit and decorative stems also make it an ideal border plant to structure your flowerbeds with elegance.

- Planting and Cultivation:

• Plant the costmary in a 3 to 5-liter pot with high-quality horticultural soil.
• Water copiously immediately after planting and place it in a bright location.
• It can also be planted directly in the ground in a sunny spot.

- Substrate / Soil Type:

Tanacetum balsamita prefers light, fertile soil. A mix of garden soil enriched with compost or organic matter like humus is perfect for ensuring vigorous growth.

- Exposure / Sunlight:

It enjoys sunny to semi-shaded locations. For optimal flowering, prioritize a full sun exposure, although it tolerates partial shade.

- Temperature / Hardiness:

This plant is hardy down to -15°C. It can withstand temperate climates, but in case of prolonged frost, mulching or shelter is recommended for protection.

- Watering / Water Needs:

It requires moderate watering. Care should be taken to keep the soil slightly moist, especially during periods of high heat, without letting it become waterlogged.

- Reproduction / Propagation:

It is mainly propagated by dividing clumps in the spring and autumn or by taking 10 cm stem cuttings in late spring. Sowing seeds is also possible but takes longer; it can be done indoors or directly in place during spring.

- Pests / Predators:

This "Hollywood mint" is generally rarely attacked by pests, but can sometimes suffer from aphids or red spider mites. Regular monitoring helps prevent infestation.

This article was written by Julien on 07/25/2026.