Equisetum

( ek - wih - SEE - tum )

At-A-Glance Information

Commonly called Horsetail, Candock, Puzzlegrass, Snake Grass, or Scouring Rush, this genus includes species of spore-producing reed-like perennial plants that grow from rhizome roots. These plants need full sun to partial shade and do well in marshy areas or near pools of water. Plants produce whorls of green stems that branch out from main ones. Horsetail species are native to temperate and arctic regions of the Northern Hemisphere, including North America, Europe, and Asia. Take care when planting these in the landscape, as some species are considered invasive in certain regions.

Equisetum Species and Varietals

The genus Equisetum is the only extant genus in the plant family Equisetaceae, which is a family of vascular plants that produce spores rather than seeds. There are 18 species in the genus. Equisetum plants grow well in USDA hardiness zones 3-11 or Sunset growing zones 1-24. To find your zone, click here: Zone Map.

Equisetum arvense (Field Horsetail, Common Horsetail, Bottle-Brush, Devil's Guts, Foxtail-Rush, Horse Pipes, Horsetail Fern, Meadow-Pine, Pine-Grass, Snake-Grass, Marestail)
This species is a perennial herbaceous plant that reaches up to 35 inches tall when mature. It grows from a creeping rhizome and produces sterile and fertile stems appearing around the same time of the year. This species is considered invasive in New Zealand, the United Kingdom, and Europe.

Equisetum giganteum (Southern Giant Horsetail)
This species is native to South and Central America and is one of the largest species in the genus. Stems can reach up to 16 feet tall and bear whorls of very slender branches, some terminating in spore cones. Stems are green. This species is considered a weed in some areas, and can spread beyond cultivated areas, but is not labeled as invasive.

Equisetum hyemale (Rough Horsetail, Scouring Rush)
These evergreen perennials are native to Eurasia and Greenland, and forms colonies in moist habitats. Plants produce reed-like stems that are green. At each joint, there is a narrow black-green band, causing the plants to have a striped effect. Stems are deciduous in cold climates. Rough Horsetail is considered invasive in North America (California), South Africa, and Australia.

Equisetum myriochaetum (Mexican Giant Horsetail)
These plants are native to Nicaragua, Costa Rica, Colombia, Venezuela, Ecuador, Peru, and Mexico. It is the largest species in the genus, reaching up to 15 feet tall on average (exceptionally up to 24 feet tall). These are semi-aquatic plants and are found growing on riverbanks in their native range.

Equisetum pratense (Meadow Horsetail, Shade Horsetail, Shady Horsetail)
This species is native to forests and meadows in many regions in the Northern Hemisphere. It produces green slender stems to 21 inches tall when mature and grows from a rhizome root. Branches are produced in whorls at nodes.

Equisetum telmateia (Great Horsetail)
This species has an unusual distribution, including Western North America, Europe, Western Asia, and Northwestern Africa. This herbaceous perennial doesn't produce flowers, and instead reproduces through spore-bearing fertile stems. It is usually found in damp shaded places within woodlands, and can be seen forming large colonies. These plants are considered invasive in the Pacific Northwest (Oregon and Washington).

Caring for Equisetum

Plant Equisetum in a moist or boggy space in the landscape that receives full sun; ideally, they appreciate between 6 and 8 hours of sun each day for the best growth. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 4.0 and 7.5 (acidic to neutral). Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water new plantings regularly as they establish a strong root system in their new home. At maturity, these plants perform well in consistently moist to boggy soils. They thrive in standing water up to 4 inches deep.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. Prune Horsetail in late winter to early springtime, cutting stems to ground level to manage height, improve airflow, and remove damaged, dead, or yellowing foliage. It is recommended to bury a barrier under the soil to prevent the rhizome roots from spreading into areas of the landscape where they are unwanted. Every so often, Horsetail will need to be divided to ensure ongoing health.

Propagation

Equisetum plants are best propagated via division. To propagate your Horsetail by division of existing plants, follow the instructions below:

Propagating Equisteum by Division
To propagate via division, you will need a clean shovel, clean pruning saw (optional), extra pots if you are not going to immediately plant your divisions in the ground, and well-draining soil to fill the pots. To propagate your Horsetail by division, follow the instructions below:

In early fall or early springtime, identify the area of plants you're going to divide. Start by loosening the soil around the plant with your shovel, working your way inward to avoid causing damage to the bulbs. Once you've gotten your clump out of the ground, run water over it or simply shake it to remove excess dirt. Then, lay it out on its side.
Separate the clump into multiple pieces, each with a healthy root system and adequate above-ground growth.
Prepare the planting area, whether it is a container or bed in the garden, and then plant the divisions. Afterwards, resume regular care.

Problems and Pests

Certain species are considered invasive in some regions; see the species descriptions above for more information. Check with local authorities before planting. Equisetum can be susceptible to developing issues with the following pests and diseases in the landscape: