If you’re looking for a water plant that’s unique and unusual, and you don’t mind a bit of a challenge, then take a look at horsetail (Equisetum hyemale, also known as scouring rush). With its stiff, hollow, bamboo-like green stalks, E. hyemale adds an exotic note to any water or bog garden. This evergreen perennial does not flower, but has small, scalelike leaves tightly bound into grey sheath at intervals around the stalks. Horsetail is extremely invasive and difficult to eradicate once it’s established, but if you follow a few precautions you can enjoy its handsome, quirky good looks without ruining your reputation.
Common name: horsetail, scouring rush, rough horsetail
Botanical name: Equisetum hyemale
Plant type: Aquatic perennial
Zones: 3 to 11
Height: 2 to 4 feet
• Sun: Full sun to part shade
• Soil: Tolerates many soil types and up to 4 inches of standing water
• Moisture: Medium to wet
• Mulch: None needed.
• Pruning: None needed.
• Fertiliser: None needed.
• By division.
Pests and diseases
• No major insect or disease problems.
• Always grow horsetail in a container, whether in soil or water. If it’s in your water garden, it should be in a pot sunk into the water to contain the rhizomes.
• E. hyemale looks great in Japanese gardens, bog gardens, and water gardens, and is striking as a vertical accent in large patio containers.
• All parts of horsetail are poisonous.
• If you have a wet or boggy area that you want covered quickly, horsetail could be your plant. But be sure that the area is bounded by some type of barrier (like sidewalks or driveways) and is not adjacent to any waterway or natural area. Also be sure that you do want horsetail to inhabit that space permanently.
All in the family
• The genus Equisetum is found on every continent, except Antarctica.
• Equisetum is the only surviving genus of a class of primitive plants that evolved more than 350 million years ago. It reproduces by spores rather than seeds.
• The common name “scouring rush” comes from the fact that the stems have a high silica content and can be used to scrub and polish metal or wood. Equisetum is not a rush, however.