Record invasive plants in your garden.

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Plant Alert is a citizen science project for gardeners. Help other gardeners and protect the countryside by warning about invasive plants before they become a problem.

Keeping ornamental plants in the garden

While maintaining the benefits and contributions of non-native plants to our gardens, we need to know at an early stage which of those plants might go on to endanger habitats outside gardens. Gardeners across Britain and Ireland can play a crucial role here: they are likely to be the first to notice any ornamental plants showing signs of invasiveness.

Data collected from Plant Alert will be used in risk assessments of species as well as to provide gardeners and nurseries with advice on which plants could also become difficult to manage in gardens.

Himalayan Balsam

Himalayan balsam (Impatiens glandulifera) escaped from garden cultivation.
photo credit: Maja Dumat

Which plants should be reported?

Many ornamental plants in your garden will spread and this is a sign that they are growing well. We only want to know about those that are spreading to an extent that you have to control them to prevent them overgrowing other plants or parts of your garden where you do not want them. We are not really interested in garden weeds, i.e. plants that are not used as ornamental plants and may be growing in your garden (e.g. couch grass, dandelion). However, if you are not sure if a plant you have to manage in your garden is a weed or an ornamental, just report it.

Why report invasive garden plants?

Invasive non-native plants are causing major problems for native biodiversity, ecosystems, infrastructure, the built environment and human health. The majority of invasive plants have been initially introduced as ornamental garden plants and then spread from gardens into the wider environment. To prevent more species becoming invasive, gardeners can contribute by reporting early signs of invasiveness of ornamental plants in gardens.

Are all non-native plants a problem?

Only a minority of escaped ornamental species are causing problems. Well known examples include Japanese Knotweed (Fallopia japonica), Rhododendron (Rhododendron ponticum), Himalayan Balsam (Impatiens glandulifera) and several aquatic plants. The challenge is to identify the potential future problematic plants out of about 70,000 ornamental plants available to gardeners in Britain.