The Anthropocene is causing a global crisis in recent decades. Facing this challenge, increasing attempts are being made to explore the more-than-human-centred perspective in HCI and design. Our research sets out to explore the ways of experiencing and interacting with plants with a case study on the slowness of plants. Utilising existing time-lapse technology, we investigate the role of IoT technologies in associating biological slowness with the networked technological environment of the home. In the experiment, we chose the humidity level of the environment as the variable to synchronise the movement of smart curtains and plants. We propose a relationship-centred strategy that uses an inclusive feature of a microclimate, like humidity, instead of the plant itself, for human-plant interaction. Furthermore, it indicates a 'plant-decentred' perspective to spark critical reflection on the taken-for-granted perception of isolating a person or a plant as an individual entity.