Rosemary (Salvia rosmarinus; until 2017 Rosmarinus officinalis)
Polar Plant, Compass-Weed, Compass Plant, Incensier (Old French), Romero, Pilgrim’s Flower, Rose of Mary
About This Plant
Few plants have retained their popularity throughout history as much as beloved Rosemary. Its history is rich and colorful, its aroma and culinary applications flavorful, and its medicinal attributes admirable. Rosemary, rich in volatile oils is a member of the Mint, or Lamiaceae, family. It is a fragrant, evergreen shrub that is a perennial in USDA zones 9-11 and treated as a tender perennial, annual, or overwintered as a houseplant elsewhere. In its most suited growing conditions, it grows as an upright shrub with needle-like leaves up to four or five feet high and can be pruned into formal shapes or used for topiary. It is pest-resistant and can retain its attractiveness for many years.
There are many cultivars of Salvia rosmarinus, also known as Rosmarinus officinalis. Many are upright, shrub or hedge-like, while others are trailing and more ground-cover-like in their growth habit. Rosemary is drought tolerant. It is used as an ornamental plant in gardens, for xeriscape landscaping, and for culinary or medicinal herb gardens. It is native to the Mediterranean region including France, Spain, Portugal, Tunisia, and Morocco, and thrives in coastal areas. Adapted to grow on wind-swept hillsides with rocky, well-draining soil, ocean mists, and other harsh climates, it produces essential oils and other compounds to protect itself from insects and diseases as well as excessive sun exposure and water loss.
Rosemary’s opposite, evergreen, needle-like leaves are ¾” to 1 ½” long. Its leaves are shiny green or dark green on top and silvery-white on their undersides. It is covered in short, dense, wooly hair. The bark on its branches is fissured. The plant blooms in tiny white, pink, purple, or blue flowers in the Spring and Summer in temperate climates. In warmer climates, the plant can be in constant bloom. While the entire plant is aromatic, the volatile oils are most concentrated in the calyces. The aroma of Rosemary is pungent, described as an intense camphor or piney scent. It has a sweet, resinous flavor. Rosemary is one of the most widely used essential oils in the world. It takes about 75 pounds of Rosemary to steam distill one pound of essential oil. The higher Rosemary grows in elevation, the more camphor it produces to survive the harsh climates, producing up to 20% camphor in high plateaus.
Rosemary has been cultivated for over 5,000 years. The first mention of it is found on cuneiform stone tablets from as early as 5,000 BCE. It has been found in Egyptian tombs from 3,000 BCE. Greek scholars wore garlands of Rosemary on their heads to aid their memory during exams. Rosemary made its way to China from the Mediterranean region as early as 220 CE during the Han Dynasty. It was cultivated by the Spanish in the 13th century where it became an important condiment for salted meats. Rosemary became an emblem of fidelity for lovers and was the subject of many poems. Shakespeare mentions it in five of his plays. There was a popular folk saying that where Rosemary flourishes, the lady rules – meaning that women ruled the home, not men. A sprig of Rosemary was often placed in the hands of the deceased at funerals as a symbol of remembrance. Brides wore Rosemary at their weddings because it is also a symbol of happiness, loyalty, and love. An old French name for Rosemary is Incensier – due to the fact it was used as a replacement for more expensive incense in their religious ceremonies. Legend tells that Rosemary originally had white flowers until the Virgin Mary placed her blue cloak upon it while resting during her flight to Egypt. The Spaniards call it “Romero” the Pilgrim’s Flower. In both Spain and Italy, Rosemary was considered a safeguard from witches and evil influences. The Sicilians believed that young fairies, taking the form of snakes lie amongst its branches. Rosemary was burned in sick chambers to purify the air and prevent infection. Nurses brewed it into a tea to make an antiseptic wash with which to sterilize medical instruments. In the Bubonic plague of 17th century France, four famous thieves managed to avoid sickness while they looted rich people’s houses. When caught and sentenced to death, they revealed the secret to their health – vinegar infused with herbs including Rosemary, Angelica, Sage, Mint, and Lavender – a recipe still used today in “Four Thieves” blends. Rosemary was added to meats and sausages prior to refrigeration (along with Oregano and Thyme) as a preservative, and to hide its “off” taste.
Rosemary is commonly referred to as the Herb of Remembrance for its ability to strengthen memory and sense of clarity. It was considered a sacred herb to Venus and Aphrodite, ancient goddesses that rose from the sea. Still popular today, Rosemary can be found in body care products, haute cuisine, and modern medical studies focused on cancer, arthritis, heart disease, and Alzheimers.
Rosemary is now considered one of the many hundreds of species in the Salvia genus. It was formerly placed in the much smaller Rosmarinus genus which only contained two to four species. There are many varieties of Rosemary, some are silver and gold-striped. The green-leaved variety is the kind that is used medicinally. Some varieties are small, creeping plants that stay under a foot tall, while others are large bushes, growing up to six feet tall.
Rosemary grows extremely slowly from seeds and may take years to reach a useable size. Seeds can also be tricky as they need to be planted fresh and in optimum growing conditions for successful germination. Germination takes two to three weeks. Rosemary is grown much more commonly from cuttings. Stems can be cut two to four inches long and the leaves removed from the bottom two-thirds of the cutting. The cutting can be placed in a mixture of perlite and peat moss or coconut coir and sprayed with water until the roots begin to grow. Once the cutting is rooted, it cat be transplanted into its permanent growing location. Cuttings tend to grow quickly in ideal conditions and should be ready for outdoor planting in about eight weeks.
Rosemary can be planted outside once the soil temperatures reach about 70 degrees Fahrenheit. If treated as an annual, it can be spaced about ten inches apart. If being treated as a perennial, allow two to three feet between plants. Plants that are being grown in the ground tend to not transplant very well.
Rosemary is a plant that thrives in warm, humid environments and is native to the Mediterranean. Keep this in mind as you determine how to best keep your Rosemary happy. It loves full sun and will not tolerate shade. It is extremely heat tolerant and won’t tolerate temperatures below 30 degrees Fahrenheit. It can withstand small amounts of snow, as long as it doesn’t last for very long and the temperature remains above 30 degrees. It prefers to be somewhat on the dry side, so the soil must be very well-draining. If planting it in the ground, consider adding some sand to its soil. If planting it in pots, terra cotta ones are a good choice as they’ll let the roots breathe easier. It is said that Rosemary can survive with just sea mist and ambient humidity in its native lands. Applying fertilizer will dilute the oil content of the plant and diminish its fragrance.
If growing Rosemary indoors or bringing it inside for the Winter months, place it in a sunny window, preferably in a cool room. Indoor-grown Rosemary needs additional humidity, so giving it a regular misting of water helps as well as placing its pot on a pebble-filled saucer filled with water. Don’t confuse the need for additional humidity with the need for more watering. The soil should still be kept on the dry side. Wet soil leads to root rot and the loss of the plant. An unhappy indoor Rosemary develops brown leaf tips and begins to die back. The plants are prone to becoming root bound and should be repotted once a year. When the lower foliage starts to yellow, it’s a sign it’s time to re-pot it.
Rosemary will often develop white foamy droplets on its foliage. This is caused by spittlebugs who suck the juices of the plant and bury themselves inside the spittle for protection. Giving the plants a strong spray of water will be sufficient to knock the bugs off the plant but they can return quickly. They typically don’t actually cause much of a problem to the plant. When Rosemary plants look to be suffering and dying, it’s typically due to soil problems and the roots having a hard time “breathing” because of poor drainage. Avoid planting Rosemary in low spots or anywhere water accumulates. Rosemary can grow quite large and retains its attractiveness for many years. It can be pruned into formal shapes, low hedges, and even used in topiary. Some people like to shear their Rosemary into the shape of a festive evergreen tree. Pruning the plants will encourage a tighter, more compact plant. Whenever you trim your Rosemary, or if you feel your Rosemary is on its way out, be sure to take cuttings and re-pot them for the next season or to give them away to your friends and neighbors.
Rosemary can be harvested for culinary use at any time. The optimal time to harvest for the best flavor or oil content is just prior to flowering, usually in May. Never take more than one-third of the plant at a time. Use fresh or dry it. It’s important to dry it quickly to help retain its green color and essential oils. Cut longer stems and bundle four to six springs at a time. Hang them upside down in a dry place with good air circulation out of direct light. Fresh leaves can also be placed in ice cube trays with olive oil or water and frozen then stored in ziplock bags.
To harvest Rosemary seed, wait until the flowers are turning brown. Collect the flowers and put them in a small paper bag for about 2 weeks or until the flowers are completely dry, Shake daily to rotate the flowers. Once dry, shake the bag vigorously to separate the seed from the blossoms or lightly rub the flowers through the palms of your hands. Winnow the plant material to separate the seed from the chaff. Seeds lose their viability quickly and are best planted soon after collecting.
Rosemary has a bitter, astringent taste and a characteristic aroma that complements many cooked foods. It should be used sparingly, as an accent to food, as the flavor can be somewhat pungent and resinous. Its pungency compliments poultry, fish, lamb, and beef. It pairs well with tomatoes, cheeses, eggs, potatoes, squash, soups, grilled or sauteed vegetables, and salad dressings. Its well-developed woody stems can be used as skewers for shish kabobs. Perhaps, surprisingly, Rosemary goes well with both savory and sweet dishes. It pairs well with fruit, chocolate, and caramel flavors. For a bit of inspiration, check out the book Herbal Kitchen where chef Jerry Traunfeld shares recipes for Warm Maple Rosemary Banana Splits and Pear Rosemary Upside Down Cake. Rosemary is delicious in teas and cocktails. A sprig of it can make an artful addition to beverages. Try it in lemonade. It pairs wells with many herbal teas including Mint, Rose, Sage, and Lavender. Rosemary can also be infused, fresh or dried, into vinegar, honey, wine, or liquor.
Rosemary is a very chemically complex plant and one that is being studied in depth by medical science for how it can affect diseases such as cancer, arthritis, heart disease, and Alzheimers. It is a plant that is loaded with antioxidants. Rosemary is a tonic for the entire cardiovascular system. It contains many types of flavenoids that strengthen capillaries and counteracts conditions such as spider veins and varicose veins. It strengthens the heartbeat, helping the heart work more effectively, and increasing arterial blood flow. Studies have shown that long-term daily intake of Rosemary prevents thrombosis. An old folk remedy is infusing red wine with Rosemary “for health”. It has a warming effect that is beneficial for those who tend to be cold, pale, and tired but without apparent disease. Drinking Rosemary tea can bring blood to the surface of the skin, warming cold extremities. Increased circulation decreases pain by relaxing tense muscles. Like Willow, it contains salicylic acid. By increasing circulation, it also helps induce sweating, thereby helping to reduce fevers. Its carsonic acid counteracts free radical damage in the brain and strengthens eye health. Its rosmarinic and ursolic acids have been linked to anti-inflammatory affects. Rosemary also moderates the breakdown of acetylcholine, a chemical that is often deficient in people with Alzheimers. Research is also showing that Rosemary slows the proliferation of cancerous cells in breast cancer and leukemia.
Rosemary can help enliven our nervous system, helping to relieve feelings of weakness, exhaustion, depression, and mental fog, bringing about feelings of mental strength and clarity. It is utilized to help clear negative memories, opening the way for healing. Rosemary can rejuvenate us. It helps to recover a diminished sense of smell as well as improves digestion and stimulates appetite. It relieves bloating and gas and can help build healthy microflora in the gut. Drinking it as a hot tea helps clear congestion from the head and chest. Its high essential oil content has antimicrobial action and is often employed in mouthwashes, teas, and tinctures for gum health, to fight bad bacteria, and improve bad breath. It also is used to relieve headaches. Oil of Rosemary is used in hair tonics, shampoos, and rinses for its scent and for its effect in stimulating the hair-bulbs, useful in conditions of hair loss and premature balding.
When used as a culinary herb, Rosemary is considered completely safe. It is not safe in large doses however during pregnancy or breastfeeding or if you are taking anticoagulant drugs, a prescription diuretic, or have pulmonary edema. Its high volatile oil content means that in large quantities it can cause serious side effects such as vomiting, spasms, coma, and even pulmonary edema. People with high blood pressure, ulcers, Crohn’s disease, or ulcerative colitis should avoid it. In large doses, Rosemary may alter blood sugar levels and could interfere with drugs taken for diabetes. Rosemary oil can be toxic if ingested and should never be taken internally.
Rosemary is native to the Mediterranean region, including France, Spain, Portugal, Tunisia, and Morocco.