Home herb gardeners are growing hyssop (Hyssopus officinalis) for its dark green leaves which are used to flavor salads, soups, liqueurs, and stews.
These attractive plants have woody stems, small pointed leaves, and spikes of pink, red, white, and blue-purple flowers. Blooms are very attractive to bees and butterflies. Hardy perennial grows 2-3 feet tall.
Native to southern Europe, Hyssop was used as early as the seventh century as a purifying tea and for medicine. The ancient herb is said to cure all manner of ailments from head lice to shortness of breath.
Learn how to plant and grow this special ancient herb in your garden with this easy guide.
Botanical Name: Hyssopus officinalis
Common Name: Hyssop
Family: Lamiaceae
Plant Type: Herbaceous perennial herb
Hardiness Zones: 4 – 9 (USDA)
Sun Exposure: Full sun to partial shade
Soil Type: Chalky, loam, well-draining soil
Soil pH: 6.6 – 8.5
Maturity: 75-85 days from seed
Height: 12 to 24 inches
Spacing: 12 to 24 inches apart
Bloom Time: Spring to fall
Quick Guide: Planting, Growing & Caring for Hyssop
- Medium-sized plant whose leaves are used for salads, liqueurs and soups
- Flowers are pink, red, white, and purple
- Start seedlings indoors 8-10 weeks before the last frost; be patient with germination
- Set seedlings outdoors after the last frost
- Choose a site with full sun and dry soil that drains well
- Best used fresh
- Very few pests and diseases — considered an excellent companion plant
Hyssop Plant Care
The hyssop plant (Hyssopus officinalis) is native to southern Europe and the Middle East. These days, it has become a native plant throughout northern Europe and North America, where it can be seen thriving on the edges of roads and in wildflower meadows.
Hyssop is a member of the mint family (Lamiaceae), and as such, it exhibits many characteristics of its mint cousins, including the shape of its flowers, square stems, and intensely fragrant leaves. Fortunately, it lacks the tendency to spread rapidly and invasively that many mint species do.
The essence of the plant has been infused into liqueurs, sauces, puddings, and candies, and it has also been used to add fragrance to soaps and perfumes. However, hyssop is more than just a culinary or medicinal herb. It also has the potential to be a great ornamental plant!
It is beautiful in rock gardens, as a border plant, as a focal point, or in clusters, thanks to its green leaves and vibrant flowers that attract pollinators. Its nectar produces great honey, so beekeepers enjoy it as well.
The hyssop oil that comes from this plant has antibacterial, insecticidal, and antifungal properties.
The Persians used hyssop oil as a body lotion in ancient times to promote skin health and to accentuate skin color and tone.
In Europe, the oils were burned as an air freshener, while in other parts of the world, the leaves were brewed into a tea to treat respiratory issues including nose, throat, and lung problems.
Hyssop leaves were also used to make topical ointments that were used to treat wounds and infections.
Light
Hyssop plants prefer full days of warm sun but may tolerate some shade. Make sure your plant gets at least six hours of sun per day for optimal growth.
Soil
It favors fertile, well-draining loam, yet it can also tolerate poor, dry, sandy soil. Hyssop grows well in a pH range of 6.6 to 8.5.
Water
Hyssop plant requires consistent watering until it is established, after which it is drought tolerant. Water deeply after the top few inches of soil have dried out for optimum plant health.
The same holds true for plants grown in containers, albeit the interval between drying out and watering will be shorter.
Use a watering can or timed drip hoses to water plants at soil level in the morning, Be careful not to get the leaves wet. Plants don’t need to be watered in the winter.
Temperature
This herbaceous plant grows best in USDA zones 4 to 9. It does not typically need any frost protection and is cold hardy down to about -35°F.
In cooler climates, plants may look a little rough around the edges, but a good pruning in the spring will take care of that.
Fertilizer
When the first shoots emerge in the spring, fertilize hyssop plants with a high-quality, balanced liquid fertilizer.
Add a slow-release fertilizer to container-grown plants in order to replenish the nutrients that were lost while watering.
Pruning
Let the dead stems and leaves stand over the winter. For a compact habit and to prevent the plant from turning spindly, cut everything back to two inches from the ground in the spring and again after flowering, if you’d like.
It is a good idea to deadhead this plant if you don’t want tiny hyssops popping up all over your yard because it self-seeds easily.
Every four to five years, replace mature specimens with new plants if you’re keeping your plant as a herb. As plants age, they get woody, and their quality deteriorates.
If these plants are purely ornamental, they can live long, bushy lives as tough, woody plants without needing replacement.
How to Plant and Grow Hyssop
Site Preparation
Hyssop prefers full sun to partial shade and dry, well-drained soil. Prior to planting, work in plenty of organic matter, such as compost or aged animal manure. It is also helpful to add a light application of organic fertilizer to the planting hole.
Hyssop will grow equally well in containers, rock gardens, and window boxes. Read our article Herbs in Pots here.
How to Plant Hyssop from Seeds
When you’re buying hyssop seeds or plants, always make sure that you’re buying Hyssopus Officinalis and not Anise Hyssop. While they have similar sounding names, they’re both completely different plants!
Sow seeds indoors just beneath the surface of the soil 8-10 weeks before the last frost. Hyssop seeds will germinate in 14-21 days. Transplant out in the spring after the last frost. Set plants 12-24 inches apart.
In autumn, new plants can be created by root division. Pruning to the first set of leaves after flowering will create a more compact plant and better flowering in the following year (watch How to Grow an Herb Garden — video).
How to Harvest and Store Hyssop
Harvest the youngest leaves and stems as needed. Cut in the morning after the dew has dried for optimal flavor. Do not wash the leaves or aromatic oils will be lost.
Hyssop is best used fresh but can also be stored frozen in plastic bags or dried. To dry, tie the cuttings in small bundles and hang them upside down in a well-ventilated, dark room. When dry, remove the leaves from the stems and store whole. Crush or grind just before use (watch How to Dry Herbs — video)
Seed Saving Instructions
Seeds are ready to harvest when the seed capsules are completely dry and brown. The capsules can then be picked and the seeds easily separated by hand.
Common Pests and Plant Disease that Affect Hyssop
Thanks to the aromatic oils this plant contains, it naturally repels most pest insects.
In fact, several articles suggest that the perennial herb repels flea beetles and cabbage moths when planted in vegetable gardens. This is why hyssop is often grown as a companion plant with cauliflower, cabbage, and grapes.
On the other hand, the plant diseases that occasionally damage hyssop are caused primarily by poor soil drainage.
If your plant’s leaves are yellowing and wilting, dig it up and inspect the roots. Root rot causes discolored and mushy root ends.
Remove any diseased roots and replant them in soil that has been amended with sand or tiny pebbles to promote drainage.
Although uncommon, powdery mildew can also harm hyssop plants.