Stinging Nettle

Stinging nettles are a common plant that can be found in many parts of the world. They have medicinal properties and grow in the same locations year after year. Stinging nettle stems and leaves are coated in structures that resemble hairs but are soft and hollow.

There are two main types of nettle – annual nettles (Urtica urens) which completes a life cycle (seed to seed) within one growing season/calendar year. The other type is perennial nettles (Urtica dioica) which will continue to regrow, over a few seasons. 

Controlling stinging nettle can be a futile exercise, as the plant not only grows quickly but also sprouts from underground rhizomes and spreads easily through wind-dispersed seeds.

This blog post will provide an in-depth guide on what stinging nettles are, how they grow, and how to eradicate them from your garden.

Quick Facts

Common names: common nettle, stinging nettle, nettle leaf, tall nettle, nettle, or stinger Scientific name: Urtica dioica Family: Urticaceae Origin: native Flowering season: April to October Habitat: alongside borders, lakes and streams

Stinging Nettle Identification

Stinging nettle is dioecious, which means plants can have either male or female flowers.

Nettles thrive in damp, nitrogen-rich soil; look for it in bottomland along rivers and streams, around old farm-steads, and in other full-sun to partially shaded areas with well-fertilized dirt.

Stinging nettles can grow between 2 and 5 feet.

There are many varieties that are easily confused with Stinging Nettle and can be found in several different places. Some of these belong to the Urticaceae family, while others do not. The following are examples of related species or look-alikes:

• False Nettle (Boehmeria cylindrica)
• Horsebalm (Collinsonia canadensis)
• White Snakeroot (Eupatorium rugosum)
• Hemp Nettle (Galeopsis tetrahit)
• White Deadnettle (Lamium album)
• Wood Nettle (Laportea canadensis)
• False Nettle (Boehmeria cylindrica)
• Horsebalm (Collinsonia canadensis)
• White Snakeroot (Eupatorium rugosum)
• Hemp Nettle (Galeopsis tetrahit)
• White Deadnettle (Lamium album)
• Wood Nettle (Laportea canadensis)

False Nettle (Boehmeria cylindrica)

The False Nettle is a herbaceous perennial that has an erect stem, with long narrow leaves which have rounded teeth on the margin and densely covered with stinging hairs. It blooms from April to June or July producing purple flowers on leafy spikes at nodes of branches.

False nettles are not native but it was introduced by humans using them as animal feed or fertilizer so no one knows exactly when these weeds first arrived. They grow best near water sources like streams, ponds, rivers, and embankments.

The leaves of false nettle have smoother toothed margins, and the leaves themselves are slightly larger at the base. Unlike stinging nettle, the stems of each flower cluster are upright and angle upward from the stem (which are droopy).

This plant has no stinging hairs on any part of it. This is despite the fine hairs found on the leaves and stems

Horsebalm (Collinsonia canadensis)

Horse balm is a wildflower that grows in moist to wet areas and can be identified by its erect stem with larger leaves than the false nettle.

This plant belongs to the Lamiaceae family of mints. Like stinging nettle, the plant grows to be about 2 feet (0.61 m) to 4 feet (1.2 m) tall, with oppositely arranged leaves.

The leaves are broad, serrated, oval, and serrated. It has a citronella-like scent to it. Flowers are tubular in form, branched, terminal spikes, and whitish-yellow to yellow in colour.

White Snakeroot (Eupatorium rugosum)

Since this plant belongs to the sunflower family (Asteraceae), it lacks stinging hairs. This plant is smaller than stinging nettle, rising to a height of 1.5 feet (0.46 m) to 3 feet (0.91 m).

The stems are normally hairless and light green to tan in colour.

The leaves are larger than those of stinging nettle, measuring about 5 inches (13 cm) long and 3.5 inches (8.9 cm) wide, and are alternately arranged along the stem. As the stem grows longer, the size of the leaves shrinks.

On top, they’re typically a darker green (light below). Serrated margins, heart-shaped near the bottom, and lance-shaped near the top, characterise the leaves.

Flowers are white and arranged in branching clusters on the plant’s top, but some flowers also branch out from the leaf’s base.

Hemp Nettle (Galeopsis tetrahit)

In some areas, hemp nettle and stinging nettle are easily confused because they grow in similar conditions and are found in similar places. However, unlike the true nettle, this plant is imported from Europe and does not have stinging hairs. Hemp nettle belongs to the Lamiaceae family, not the Urticaceae.

Hemp nettle has bristly hairs on the stems and leaves and is shorter than stinging nettle. It also has wider leaves (though their form varies from oval to lance-shaped) and pink, white, or variegated flowers that emerge from the leaf’s base.

The plant itself is a darker green colour than stinging nettle. This species is an annual that grows from seed spread by animals or spread by pre-existing hemp nettles, as well as human activity.

In some parts of North America, hemp nettle is considered a noxious weed.

White Deadnettle (Lamium album)

This perennial is native to Europe and has been introduced to North America as a member of the Mint family (Lamiaceae). It grows to be about 1.5 feet (0.46 m) to 3.2 feet (0.98 m) tall, which is shorter than a stinging nettle.

Both the leaves and the stems are covered in bristly hairs, and the leaves are arranged opposite the stem. The leaves are oval and heart-shaped, with greater tooth margins than stinging nettle.

The flowers are white and set in a whorl at the axils of the leaves on the stem.

White Deadnettles are perennial weeds but they do not take over an area when left uncontrolled like some of their counterparts might be inclined to do. They have no natural predators which mean control efforts such as physical removal of herbicides must be done by humans.

Although controlling this plant without chemicals may seem difficult at first.

Wood Nettle (Laportea canadensis)

Just like the Stinging Nettle, has similar stinging properties and belongs to the same family (Urticaceae). Plants are usually shorter than stinging nettle, growing to a maximum height of 4 feet (1.2 m).

The leaves of wood nettle, on the other hand, are broader and wider. Usually, these leaves are 6 inches (15 cm) long and 4 inches (10 cm) thick. They are almost egg-shaped or oval in shape but have a sharp tip and serrated edges, similar to stinging nettle.

The leaves have a wrinkled appearance, particularly at first, but this fades as the leaves mature. Unlike stinging nettle, which has opposite leaf arrangement, the leaves of this plant alternate along the stem.

Flower clusters are droopy, similar to stinging nettle, but they are born on cymes (branching flower clusters) at the plant’s top. Male flowers bloom in the leaf axils, while female flowers bloom at the top of the plant.

Unlike stinging nettle, wood nettle has branching flower clusters at the top of the plant.

Wood nettles are extremely fast-growing plants. They can be identified by their green, shiny leaves and the clusters of flowers that they produce in early summer.

These plants grow best in moist soil or ground areas with poor drainage which means you should watch out for these little guys at footpaths!

Northern Bugleweed (Lycopus uniflorus)

The shorter height (1 foot (0.30 m) to 2.5 feet (0.76 m) of this plant, as well as its leaves (opposite on the stem) and white flowers, distinguish it from the stinging nettle.

The leaves are smaller, with lengths varying from 1.5 inches (3.8 cm) to 4 inches (10 cm) and widths ranging from 0.5 inches (1.3 cm) to 1.5 inches (3.8 cm).

They have 5 to 7 teeth along each leaf edge and are elliptic to broadly elliptic in shape. Flowers are small, white, and tubular, with 4 to 5 tiny lobes.

Northern Bugleweed is a stingless member of the mint family (Family Lamiaceae).

This plant can be identified by its fuzzy, light green leaves and its clusters of white flowers. It will grow in any type of soil but prefers dryer areas so check the edges of footpaths for these little guys!

Horehound (Marrubium vulgare)

The various bushy stems and wrinkled leaves distinguish horehound from stinging nettle, which is also a member of the mint family Lamiaceae.

Both leaves and stems have a whitish, woolly pubescence. The leaves range in form from oval to egg-shaped.

White tubular flowers emerge in whorls at the leaf axils. Horehound can be mistaken for stinging nettle when young; plants take two years to bloom.

When crushed, the leaves emit a pungent, bitter odour, but the plant is non-stinging.

Horehound is a plant that can be found in the UK, Europe and North America. Its leaves are shaped like an arrowhead with a white flower at both ends of each leaf stalk.

When you crush these leaves they emit a strong scent which some may find unpleasant but it’s worth considering for your garden space to help get rid of nettles!

Spearmint (Mentha spicata)

At the pre-blooming point, spearmint may be confused with stinging nettle. The herb, which is mostly hairless and belongs to the Lamiaceae family, does not sting and has a strong minty odour.

Although the leaves are opposite, they are smaller, more lanceolate or oval-shaped, and have toothed margins that point toward the leaf tips, and they grow shorter than stinging nettle (only 1 foot (0.30 m) to 2 feet (0.61 m) long.

Spearmint flowers are a soft pinkish-purple colour. They bloom in thick spikes of whorled flowers near the top of the plant. A primary, dense spike and two smaller, lateral spikes usually make up this inflorescence.

Upright Pellitory (Parietaria officinalis)

The nettle family Urticaceae includes pellitory (or Pellitory-of-the-Wall, or Lichwort), which is related to stinging nettle. Despite having hairs on the leaves and roots, pellitory, unlike stinging nettle, does not have stinging properties.

The leaves have smooth margins and the stem is reddish. Pellitory has greenish flowers in the leaf axils, and the leaves are opposite, similar to stinging nettle.

Its leaves are approximately 12in long and pointed at the end which is where you’ll find a few small white flowers that will bloom from June to September.

The flowers, on the other hand, are arranged in whorls on the stem rather than on drooping branches.

This flower has no petals! When crushed these leaves give off a strong smell of garlic – so if you’re battling with nettles or other pesky garden weeds then maybe consider using upright pellitory as well!

It can be found in both North America and Europe.

Clearweed (Pilea pumila)

This annual is a non-stinging member of the Nettle family (Urticeae). The translucency of the stems (especially as plants age or as the growing season progresses) is the most interesting and defining feature of this plant, hence the common name.

The stems may be reddish-green, grey-green, or light-green. It is shorter than stinging nettle, reaching just 0.5 feet (0.15 m) to 2 feet (0.61 m) in height, and its leaves and stems are hairless, smooth, and shiny.

Leaves are half as long and half as wide, measuring 0.75 inches (1.9 cm) to 4 inches (10 cm) long and wide. Each leaf has a thin, membraneous texture (smooth, almost human skin-like) with a prominent mid-vein and two visible side-veins on either side of the main vein. The leaves of clearweed are more oval or ovate in shape.

Clearweed flowers are borne in small racemes that are shorter than those of stinging nettle, measuring around 1 inch (2.5 cm) in length. Each flowering stem has some branching as well.

Self Heal (Prunella vulgaris)

The purple flowers in whorls on an upright stem distinguish Self-heal from stinging nettle, as does the plant’s low-growing, relatively creeping form.

The leaves have smooth margins or small toothed edges and are roughly lance-shaped to oval in form.

Self Heal is a low growing plant that can be found in both North America and Europe. It has leaves 12in length with pointed ends, where you will find small white flowers blooming from June to September. This flower does not have petals!

Marsh Hedge Nettle (Stachys palustris)

When in the pre-blooming stage, this plant (a native of North America) belonging to the mint family (Lamiaceae) can be easily confused with stinging nettle.

There are opposite leaves and pubescent or hairy leaves and roots, much like stinging nettle. This species, however, is notably hairier than stinging nettle. When it blooms, note how it grows in a spike above the leaves, with a whorl of pink to pinkish-purple flowers.

This is one of the most common types of stinging nettles and you can find it in wet places such as marshes, ditches or near water.

The leaves are much more like grasses with a stiff stem than other plants so look for those features to tell them apart from others ones that we have talked about already!

Marsh hedge nettle has small yellow flowers on their stems which grow towards the end of long branches. They will also be found growing at different heights in marshy areas but they don’t spread very quickly which makes them easier to remove from an area.

What do Stinging Nettles look like?

The leaves of the nettle plant are what cause the stinging sensation – they contain a chemical called histamine that can be released when touched, which produces an allergic reaction in people!

The branches on this plant have stiff hairs with small hooks/barbs that get stuck to your skin or clothes.

This is how it causes irritation as you walk through them; if you touch any other part of its body afterwards it will also release these irritating chemicals onto your fingers and into your bloodstream.

If you brush against one part twice, then both sides will sting for around 30 seconds each time after contact with either side has been made again (once). It’s not just humans who feel these unpleasant effects animals can too.

Characteristics that make up the common stinging nettle leaf, stem, root and flower are detailed below.

Leaves have a heart-shaped base and indented veins and are pointed at the ends. Young plants have smaller, purple-tinged heart-shaped leaves, while mature plants have long, pointed leaves that are bright green.

The leaves are coarsely toothed, pointed on the ends, and can be several inches long.

Stem/hairs: Tiny “hairs” can grow up the stalk and square stems of the plant. (This is the source of the sting!).

Stinging nettle delivers a painful sting through tiny hairs on the underside of its leaves and stems, true to its name.

Trichomes, or stinging hairs, are hollow hypodermic needles with protective tips.

When the tips are struck, they break off, exposing the sharp needles.

The sting is caused by the trichomes injecting formic acid, histamines, and other chemicals into your skin.

Roots: The roots are often rhizomatous, and a parent plant may produce large colonies with a diameter of up to 8.2 feet (2.5 metres) each year. Because of their rhizomatous existence, these plants can live for a long time.

The actual plant and roots will only last for one year but the seeds sown will produce the next year’s crop. 

Some colonies have been discovered and are thought to be 50 years old or older. Although the plants themselves are short-lived, the rhizomatous nature of the plant and the pink buds that grow on the roots cause it to spread.

Flowers: The tiny flowers are arranged in inflorescences, which resemble catkins and hang from the stems.

Female flowers are green and white, while male flowers are yellow or purple.

On the axils of the stems, these branching clusters bear green flowers with only sepals and no petals. The sepals range in length from 0.04 inch (1.0 mm) to 0.08 inch (2.0 mm). There are two styles of these flowers: male and female. Wind pollinates flowers.

• Male flowers have four sepals and four stamens and are usually greenish-yellow in colour.

• Female flowers have four pubescent (hairy) sepals and one pistil, and are more green

Seeds: The female plant will produce a huge number of seeds. 

The Problem

Nettles can be found in a variety of environments, but primarily in moist, wooded or open areas including paddocks, roadsides and farmyards. Both the upper and lower surfaces of the leaves have hairs that cause a nasty sting when touched but more importantly, they can form large clumps up to 1.2m in height and will compete with other plants for nutrients, light and water and eventually completely take over a garden or field.

Stinging Nettle Seasonal Changes

Stinging nettle is a cold season perennial plant, meaning it is early to pop up in the spring.

Stinging nettles in Spring

In spring the stinging nettles appear and they are found in wetter areas like marshes, ditches or near water. The leaves are much more like grasses with a stiffer stem than other plants so look out for those features to tell them apart from others.

Stinging nettles in Summer

Stinging nettle grows from the early spring through summer and can grow to be between 3 to 7 feet tall with leaves from 1 to 6 inches long.

In the summer, stinging nettles can grow to be 3-4 feet tall, with clusters of tiny white, green, and yellow flowers on each stalk.

Since the flowers are pollinated by the wind rather than insects, they do not emit a fragrance that would attract pollinators or smell pleasant to humans.

The male flowers are at the top of the plant and release pollen into the air, which dusts the female flowers that are lower down.

Stinging nettles in Autumn

Nettles usually emerge in early summer and start dying off towards autumn; while some people think they’re gone come wintertime, others say there might still be growth happening underground level hence why it’s so important to get rid of them now if you want the problem solved once and for all.

Stinging nettles die down to tough yellow roots in autumn,

Stinging nettles in Winter

When the weather gets cold, stinging nettles will die back and then re-emerge in spring.

Stinging nettle emerges as soon as the ground thaws in late winter or early spring. Stinging nettle dies back to the ground at the first hard freeze of winter. Since it’s a perennial, it comes back in the same spot year after year, spreading via seed and underground runners.

How to get rid of Stinging Nettles

Gardeners have been getting rid of this plant for centuries using a variety of methods.

Method One – Digging it out

Wear thick gloves and old clothes before picking the nettles by hand. Be sure to remove the underground rhizomes completely or the weed will continue to come back.

Therefore, your next stage is to cut down or uproot them with a shovel, but beware as they can sometimes be very difficult to get out because the roots are strong and will grip in tight!

Tilling or cultivating a densely populated area can spread rhizomes, growing the colony rather than eradicating stinging nettle.

Stinging nettle control is difficult once again, as these underground horizontal root stems can spread 5 feet (1.5 m.) or more in a season, regrowing from the rhizomes even when broken apart.

Method Two – Herbicide Treatment

For those who don’t want any physical contact at all then it’s possible to use weed killer or herbicide which you can buy from your garden supplier, home improvement store, hardware shop etc.; just be careful not to spray it on plants that may not harm such as roses – always check first what kind of weeds you’re dealing with so there’s no risk whatsoever.

If already present, a good way to get rid is using weed killer such as Roundup which kills off all unwanted weeds where they stand

It is advisable to use a chemical spray or herbicide in a well-ventilated area; don’t do it on a windy day otherwise the chemicals will blow around and land elsewhere. Especially on plants, you do not wish to eradicate.

Management of Stinging Nettles

Plants can be dug up and removed, but the easiest method of eradication is by chemical control.

Nettles growing on bare soil or hard surfaces can be killed using a total herbicide which will kill everything it comes into contact with, including grass. For nettles in grassland, we recommend using a selective herbicide that will control the target weeds and leave the grass unharmed. 

In Conclusion

Stinging nettles are a tough plant but with this guide outlining all areas for attack, we hope you’re ready to fight back against this enemy before they get too far into your garden again!

Stinging nettles are a very adaptable weed that grows in our gardens today and is one of the most resistant. However, using one of the products mentioned below will eliminate it.

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