Bracken, Pteridium aquilinum, is widely distributed throughout the UK being by far the commonest fern. Bracken is reported to cover over 8% of the country, an area of 11,000 But it can harbour ticks and mites and its spores are considered carcinogenic and it is poisonous to cattle and horses, giving rise to ‘bracken staggers’.

Controlling bracken with Roundup

Successful control of bracken can be difficult. The main reason for this is the extensive underground rhizome network. This network consists of two rhizome types: storage rhizomes (70-80% of total rhizomes), which contain large carbohydrate reserves, and frond bearing rhizomes near the ground surface carrying a large number of frond-forming buds.

Timing of control is critical. Successful control using weedkiller is dependent on the timing of the treatment in relation to the movement of nutrients and dry matter between the underground storage rhizomes and the fronds.

As the fronds develop in spring the reserves in the storage rhizomes diminish. Treatment with Roundup during frond expansion in April, May or June will result in frond death but with little long term effect on the rhizomes as the glyphosate is carried upwards with the nutrient flow. Once the fronds are fully expanded, the products of photosynthesis will start to be translocated down to replenish the underground reserves. Treatment of the fronds as they approach full size in July-August will give maximum translocation and long term control of the stand.

Bracken is very adaptable and one of the most resistant weeds growing in our gardens today. However using one of the recommended products below will kill it.

Where to find bracken

  • In flower beds
  • At garden borders
  • Around paths from the lawn