Although many herbs are grown for medicinal and culinary purposes, many herbs are grown simply because they are durable plants and look good in the garden. Some herbs are perennials that return every year from existing growth, while some are annual and sprout from seed every year. Herbs may produce flowers of red, yellow, orange or blue.

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Rosemary produces attractive blue flowers.

Sage

Sage (Salvia officinalis) is a perennial herb used for flavoring gravies, soups and meat dishes. It is also a popular herb for medicinal purposes. Sage is a low-growing plant suitable for borders. The leaves can be picked fresh and dried for later use. The blue flowers are produced in mid to late summer.

Rosemary

Rosemary (Rosmarinus officinalis) is a woody evergreen herb used as a cooking spice as well as for medicinal purposes. It is believed that rosemary has antibacterial and anti-fungal properties. It is used to season meat dishes and even desserts. There are many varieties of rosemary with some growing low to the ground and others growing as tall as 48 inches. The blue flowers are produced along the stems in the spring and sporadically during the growing season.

Borage

Borage (Borago officinalis) grows to 2 feet high and produces blue flowers in the summer. The stems are covered with prickly hairs that make handling the plant difficult without protection. It is an annual plant that reseeds in the garden. It does not grow well where the root system is often disturbed through cultivation. The blue flowers are used as a garnish and teas are made from the foliage. Borage has a long history of medicinal use.

Chickory

Chicory (Cichorium intybus) is a perennial branching herb reaching 5 feet tall. The root is roasted and used as a coffee additive to counter the stimulating effects of coffee and the tender young leaves are eaten fresh in salads. It has a long history as a medicinal herb going back as far as the Romans. The blue flowers are produced in late spring and early summer.