Invasion strategies of the white ginger lily Hedychium coronarium J. König (Zingiberaceae) under different competitive and environmental conditions

• A trade-off for invasive Hedychium coronarium new ramets is proposed.
• As higher competition, lower number and higher heights of new ramets.
• As lower soil moisture, higher number and lower heights of new ramets.

The success of an invasive plant depends on its competitive advantage in the new community. This advantage can be attributed to high phenotypic plasticity, which either allows the plant to develop under a broad variety of environmental conditions, or grants it with a higher fitness compared to native species. In the present study, we assessed the development of the invasive white ginger lily, Hedychium coronarium, and plant community through removal experiments, under different conditions of soil moisture in riparian areas. We observed that H. coronarium exhibited different invasion strategies according to soil moisture, plant community species life form, and intensity of intra- and inter-specific competition. In areas with high soil moisture and high competitive pressure, H. coronarium invests in height growth rather than new ramets. In areas with drier soils and lower competitive pressure, H. coronarium expands its population through new ramets. Our results suggest H. coronarium has a negative influence on the recruitment of plants from the plant community, with consequences to the biodiversity of invaded areas.