How Do You Know Spring Has Arrived? Sweden's National Volunteer Plant Survey Tells You
Thousands of volunteers in Sweden conduct an annual "Spring Survey" from late April to early May to study how climate change affects plant growth. This year, spring arrived about a week earlier than usual.
📋 Article Processing Timeline
- 📰 Published: May 5, 2026 at 22:27
- 🔍 Collected: May 5, 2026 at 22:31 (4 min after Published)
- 🤖 AI Analyzed: May 5, 2026 at 22:50 (18 min after Collected)
Central News Agency
(Central News Agency reporter Ku Yung-li, Stockholm, May 5) The Nordic region has distinct four seasons, and the timing of spring's arrival varies each year due to climate change. To understand how climate change affects seasonal changes and plant growth, thousands of volunteers across Sweden conduct a plant survey annually between Walpurgis Night (April 30) and May 1, uploading their results to the "Spring Survey" database for academic analysis and research.
Sweden has a long and narrow territory, stretching approximately 1572 kilometers from north to south, so the arrival of spring varies across different regions. To understand how climate change affects seasonal changes and plant growth, thousands of volunteers across Sweden "search for spring" for two days, from April 30 to May 1, each year.
In late April, various natural, biological, and botanical non-profit organizations, educational centers, and authorities responsible for natural environment management and conservation across Sweden issued announcements through their respective social media channels, encouraging the public to participate in the "Spring Survey."
The method of the Spring Survey is simple: no special tools are needed, just a pen and an observation form. It also doesn't require going to specific locations; it can be done in nearby forests, parks, or even in one's own garden.
Volunteers observe the six most widespread plants that best represent spring in Sweden: Wood Anemone (Anemone nemorosa L.), Liverwort (Hepatica nobilis), Coltsfoot (Tussilago farfara L.), Bird Cherry (Prunus padus), Goat Willow (Salix caprea), and Birch. They record the flowering and leaf growth stages of these plants on the form.
After completion, volunteers upload their observations to the "Spring Survey" (Vårkollen) database, providing data for expert scholars from the Swedish University of Agricultural Sciences (SLU), the Swedish Botanical Association (Svenska Botaniska Föreningen), and the Swedish Phenology Network (Svenska fenologinätverket) for analysis and research.
Experts compare the collected data from various locations with similar citizen surveys conducted between 1873 and the early 1900s, identifying differences in plant growth at the same time point across different eras and climatic environments, thereby understanding the impact of climate change on phenology.
This year's survey results found that spring arrived about a week earlier than usual, and two weeks earlier compared to data from 150 years ago.
The "Spring Survey," or "Searching for Spring," is held between Walpurgis Night on April 30, symbolizing the welcoming of spring and light, and May 1, traditionally a day for Swedes to go out for excursions and even take their first swim in a lake of the year.
For Swedes who have finally bid farewell to the long winter, the Spring Survey is naturally an uplifting event. However, beyond knowing when spring arrives, this comparative data is very important for forestry and agricultural workers, beekeepers, and even pollen allergy sufferers who rely on nature.
This citizen research project, organized by the Swedish University of Agricultural Sciences, the Swedish Botanical Association, and the Swedish Phenology Network, began in 2015 and has been ongoing for 11 years. The Spring Survey is just one part of Sweden's effort to establish a "Nature's Calendar" (Naturens kalender), with national volunteer surveys continuing from the search for spring until the very end of autumn, recording the relationship between plant growth and climate change. (Editor: Yang Sheng-ju) 1150505
Choose to stand with facts; every sponsorship you provide is a force to protect press freedom.
Download the Central News Agency's "First-hand News" APP to stay updated with the latest news.
The text, images, and videos on this website may not be reproduced, publicly broadcast, publicly transmitted, or utilized without authorization.
(Central News Agency reporter Ku Yung-li, Stockholm, May 5) The Nordic region has distinct four seasons, and the timing of spring's arrival varies each year due to climate change. To understand how climate change affects seasonal changes and plant growth, thousands of volunteers across Sweden conduct a plant survey annually between Walpurgis Night (April 30) and May 1, uploading their results to the "Spring Survey" database for academic analysis and research.
Sweden has a long and narrow territory, stretching approximately 1572 kilometers from north to south, so the arrival of spring varies across different regions. To understand how climate change affects seasonal changes and plant growth, thousands of volunteers across Sweden "search for spring" for two days, from April 30 to May 1, each year.
In late April, various natural, biological, and botanical non-profit organizations, educational centers, and authorities responsible for natural environment management and conservation across Sweden issued announcements through their respective social media channels, encouraging the public to participate in the "Spring Survey."
The method of the Spring Survey is simple: no special tools are needed, just a pen and an observation form. It also doesn't require going to specific locations; it can be done in nearby forests, parks, or even in one's own garden.
Volunteers observe the six most widespread plants that best represent spring in Sweden: Wood Anemone (Anemone nemorosa L.), Liverwort (Hepatica nobilis), Coltsfoot (Tussilago farfara L.), Bird Cherry (Prunus padus), Goat Willow (Salix caprea), and Birch. They record the flowering and leaf growth stages of these plants on the form.
After completion, volunteers upload their observations to the "Spring Survey" (Vårkollen) database, providing data for expert scholars from the Swedish University of Agricultural Sciences (SLU), the Swedish Botanical Association (Svenska Botaniska Föreningen), and the Swedish Phenology Network (Svenska fenologinätverket) for analysis and research.
Experts compare the collected data from various locations with similar citizen surveys conducted between 1873 and the early 1900s, identifying differences in plant growth at the same time point across different eras and climatic environments, thereby understanding the impact of climate change on phenology.
This year's survey results found that spring arrived about a week earlier than usual, and two weeks earlier compared to data from 150 years ago.
The "Spring Survey," or "Searching for Spring," is held between Walpurgis Night on April 30, symbolizing the welcoming of spring and light, and May 1, traditionally a day for Swedes to go out for excursions and even take their first swim in a lake of the year.
For Swedes who have finally bid farewell to the long winter, the Spring Survey is naturally an uplifting event. However, beyond knowing when spring arrives, this comparative data is very important for forestry and agricultural workers, beekeepers, and even pollen allergy sufferers who rely on nature.
This citizen research project, organized by the Swedish University of Agricultural Sciences, the Swedish Botanical Association, and the Swedish Phenology Network, began in 2015 and has been ongoing for 11 years. The Spring Survey is just one part of Sweden's effort to establish a "Nature's Calendar" (Naturens kalender), with national volunteer surveys continuing from the search for spring until the very end of autumn, recording the relationship between plant growth and climate change. (Editor: Yang Sheng-ju) 1150505
Choose to stand with facts; every sponsorship you provide is a force to protect press freedom.
Download the Central News Agency's "First-hand News" APP to stay updated with the latest news.
The text, images, and videos on this website may not be reproduced, publicly broadcast, publicly transmitted, or utilized without authorization.