Bracken

Pteridium aquilinum, also known as bracken, is the most common plant on the planet, with the exception of Antarctica. They excel in the UK’s woodlands. Bracken can harbour ticks and mites, and its spores are carcinogenic. Bracken is also toxic to cattle and horses, causing ‘bracken staggers.’

Quick Facts

Common name(s): bracken, brake fern, bracken fern
Scientific name: Pteridium aquilinum
Family: Dennstaedtiaceae
Origin: native
In leaf: spring to autumn
Habitat: woodland, heathland, gardens and allotments adjacent to infested land

Bracken Identification

One of the most common questions about bracken is how to identify it. Bracken plants are usually found in shady, moist areas like forests or under trees with lots of shade.

They can range from a few inches high to over six feet tall! The leaves have needle-like structures that allow them to cling tightly to surfaces, and they grow quickly into dense clusters (called stands).

Most often you will see this plant in late summer and early autumn because these are times when its conditions – an abundance of water and low levels of sunlight – are ideal for growth.

You might be interested to know that while some plants can have two or more different types of leaves, bracken has only one type.

Brackens are in the same family as ferns and mosses, but they’re much larger than those common plants.

Some people mistake them as ferns because they both have needle-like structures on their leaves, but bracken is much taller than most ferns.

The main difference between ferns and bracken is that ferns are much more delicate and have a different leaf structure.

Closeup of Bracken infesting a woodland area
Closeup of Bracken infesting a woodland area

What does Bracken look like?

Characteristics that make up the Bracken leaf, stem, root and flower are detailed below.

Leaves/fronds: broad, green fronds with triangular divisions that alternate down the stem. The fronds are tri-pinnate, which means that the leaflets that develop on each side of the stem are divided into leaflets, and those leaflets are divided into leaflets as well.

In the spring, new fronds emerge from the base as a trio of small leaves known as pinnules. The upper surface of mature fronds is normally leathery and glossy, and they are upright and robust. They can reach a height of two metres and a width of one metre.

The fronds turn a reddish-brown colour throughout the fall, dying down to the ground level in some cases and remaining throughout the winter in others.

Bracken Leaf or Frond are tri-pinnate
Bracken Leaf or Frond are tri-pinnate

Rachis (stem): hairy, pushes up in the spring with a spirally coiled frond at the end that slowly unfolds layer by layer.

Bracken stems also known as Rachis
Bracken stems also known as Rachis

Rhizome: a perennial, fleshy, black, and hairy underground stem that can reach depths of one metre and spread hundreds of metres.

Spores: On the underside of the fronds, spore cases (sporangia) emerge in clusters. Spores are released into the wind to disperse.

Bracken fiddleheads ready to open up
Bracken fiddleheads ready to open up in early Spring

Commonly mistaken for: Buckler fern (Dryopteris dilatata), which does not grow as tall as bracken, is not to be confused with. Bracken, on the other hand, has side branches and grows from underground roots, while buckler ferns have circular crowns.

The Problem

Bracken has thick, fleshy, brown-black underground stems that can travel long distances, often spreading into gardens from adjacent countryside.

Sections of these fleshy underground stems can be introduced to the garden hidden among the roots of plants acquired from infested gardens, or in homemade compost or leaf mould.

In cool, woodland gardens, bracken may germinate from spores carried in on the wind. 

Bracken can out-compete desirable garden plants and invade bare soil, becoming a weed that is difficult to eradicate.

People who have spent all their lives living amongst bracken and breathing in the spores may be at higher risk of getting some cancers, but the danger to the general population and to casual visitors in bracken-infested areas is negligible. 

Bracken Seasonal Changes

Seeing the changes of Bracken over a year and through the seasons will help you prepare for maximum success in eradicating this weed.

Bracken in Spring

Bracken is a common weed that should be taken care of during the spring. The leaves will start to grow early, and they can go unnoticed for weeks until it starts spreading its roots in new areas. Once you have bracken growing in your garden, it’s not easy or cheap to get rid of them!

It’s a startling sight to see the ferns burst into lime-green life on its boughs. The bristly fronds stand at attention, as if ready for battle or showing off their new leafy crown.

The first step is recognizing where this invasive species has grown. If you see some green leaves popping up from below ground level, then there’s a chance these are coming from our least favourite pesky plant- Bracken!

In the Spring, this plant has a lot of new growth coming out from it. The leaves are green and have bits of yellow on them.

Brimming with life in the Springtime, bracken is covered in richly hued foliage that grows to about twenty-four inches tall.

Bracken frond spirals unfurling in spring
Bracken frond spirals unfurling in spring

Bracken in Summer

The next step is to find the roots of this weed as this is how it takes hold and spreads. Bracken will spread its wide, wiry taproots up to six inches below ground level in search of food and water- so it’s not a good idea to just cut off all the leaves!

This invasive weed loves moist environments so make sure there’s not any standing water near or below where you’re digging at all times. It also likes being close to taller plants, bushes, and grasses because they attract moisture- so keep these things away from each other too if possible.

Bracken fern growth during summer
Bracken fern growth during summer

Bracken in Autumn

The best way to prevent Bracken in autumn is by removing any leaves that remain on the plant- this will stop the weed from photosynthesising and using up all of its energy.

The leaves of the bracken are a dark, deep red-brown colour in autumn and take on an orangish hue when wet. It is common to see fallen pieces among these reddening branches as they fall off from their long stalks that will be withered and thin for next year’s return to power.

If you’re dealing with a large infestation, keep an eye out for how deep it goes down because if you leave one root system then they will grow back stronger than before!

Always be alert for new shoots emerging next year too- these ones are even more difficult to get rid of as the new growth will be much more vigorous and harder to pull out.

Golden Brown Dry Bracken in Autumn

Bracken in Winter

As the ground freezes over, your plants will become dormant. This means that they’re not going to be actively growing or photosynthesising- so you’ll have a little time before their roots grow too deep and get out of control again.

If it’s just one weed in winter then pull it up by hand from as close to the root system as possible (or use sharp shears) because freezing cold weather can kill this plant for good!

In winter, bracken is a greyish brown colour. Brackens are clumps of dry old fern leaves that seem to be dying and dead in the cold months but coming alive in warmer weather as they turn green again with new growth!

However, if there are lots of Bracken around your garden then try applying thick mulch on top of them- that way they won’t get any sunlight and therefore won’t grow at all!

The best time to apply these techniques is when the frost has hit: once temperatures rise it becomes too late.

Bracken in winter suffering from frost bite
Bracken in winter suffering from frostbite

How to get rid of Bracken

It can be difficult to keep bracken under control. The vast underground rhizome network is the main reason for this.

This network is made up of two types of rhizomes: storage rhizomes (70-80 per cent of total rhizomes), which store large amounts of carbohydrate, and frond bearing rhizomes near the ground surface, which hold a large number of frond-forming buds.

Method One – Herbicide Treatment

The timing of the weedkiller treatment in relation to the movement of nutrients and dry matter between the underground storage rhizomes and the fronds is critical for effective weedkiller control.

The reserves in the storage rhizomes decrease as the fronds mature in the spring. Roundup treatment during frond expansion in April, May, or June will kill the fronds, but the glyphosate will be carried upwards with the nutrient flow, having a little long-term impact on the rhizomes.

The products of photosynthesis will begin to be translocated down to replenish the underground reserves once the fronds have completely grown. Maximum translocation and long-term control of the stand can be achieved by treating the fronds as they reach full size in July-August.

There are many ways to get rid of bracken, but we’ve found that this option is best for most gardens: Roundup weed killer (it kills other weeds too!).

Do not apply it if you have grass or plants nearby because they will also die. Apply it directly on top of the leaves before sunrise; wait about an hour after application before walking around in your garden again as this gives time for the spray to dry.

Do not use any kind of natural repellent during this waiting period! Make sure to water first so that there is moisture present when applying weed killer overtop – otherwise, some spots might become affected by drought conditions afterwards

Method Two – Digging it out

You can get rid of Bracken in your garden by pulling it out manually or using the following:

  • Apply thick mulch on top of them- this way they won’t be able to grow
  • The best time to apply these techniques is when there’s been a frost, as freezing cold weather can kill this plant for good.
  • Dig around the roots with a shovel or spade and pull it out of the ground, then discard it in a sealed bag.

Alternatively, if you find that this is too much work for your garden or there are large patches of Bracken, try spraying with glyphosate weedkiller on any visible parts and wait 24 hours before replanting anything else.

This will kill off the plant without harming other plants around it!

It’s best to apply these techniques when there has been frost so freezing cold weather can kill them permanently- once they’ve sprouted again during warmer temperatures it becomes too late!

Management of Bracken

If you intend to gather bracken for composting or eradication purposes you are best advised not to do so in late summer when the spores are released, particularly in dry weather as this can affect your health adversely.

In Conclusion

Bracken is 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!

Bracken is 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.


How does Bracken spread?

Bracken spreads via spores and underground stems called rhizomes