A warm 2023 causes plants to flower throughout winter

What’s going on here?

Have you noticed more flowers blooming through winter? Data from the Botanical Society of Britain and Ireland shows that 2024 has seen more flowering plants than usual, thanks to unusually high temperatures in 2023.

What does this mean?

The 2024 Hunt ran from December 30^th 2023 to the 2^nd of January, and the results have just been released which you can find in their full report and summary.

Every year, the Botanical Society of Britain and Ireland hold the New Year Plant Hunt: a huge citizen science event occurring at the beginning of every year. Volunteers go out and record all native and non-native plants that are currently flowering, and the data can contribute to our understanding of how plants are responding to the climate crisis.

This year saw a 30% increase in flowering plants compared to last year’s Plant Hunt, and the third highest recorded since the initiative began in 2012. More than half of the flowering species observed on the Hunt are known as ‘autumn stragglers’, and include Yarrow and White Dead-nettle.

Last December was unusually mild: 2.8°C higher than normal on average. Plus, last summer was the second hottest UK summer on record. The autumn stragglers normally flower in midsummer but the unusually mild conditions and absence of frost meant they managed to flower throughout the winter.

The New Year Plant Hunt shows plants responding to changes in climate, but there is not sufficient data to compare this with previous years. However, historical data going back 250 years shows that plants are flowering almost one month earlier than they used to. This is starker in cities due to the urban heat island effect: man-made structures and concentrated human activity means that cities are hotter than rural areas.

Why should we care?

The impacts of changes in flowering times is still unclear, but may have concerning ecological implications. Flowering plants have evolved alongside their pollinators, such as bees, and they depend on each other. Early or late flowering may cause the two to be out of sync, preventing plants from reproducing as normal.

The cyclical nature of flowers blooming keeps us in touch with our environment, both in urban and rural settings. Author Nell Frizzell recently wrote about her feelings of grief and fear in noticing trees blossoming in January as they respond to our changing climate.

Be Curious!

• Another way plants are adapting to man-made crises: they may actually be turning away from pollination as insect numbers decline.
• Get involved with Nature’s Calendar, a Woodland Trust citizen science initiative collecting data to understand how the changing climate is affecting wildlife.
• From the Curious Archives: shifting weather may also present opportunities. Places like Norway are now experiencing weather warm enough to produce wine.

Featured image by Andrea Windolph, via Unsplash.