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Lilacs at Denver Botanic GardensPhenology examines phenomena like blooming in the spring and leaf color changes in the fall. Scientists are interested in the timing of biological events like these and their relationship to our climate. In ecological research, understanding phenology is critical to the timing of seasonal work like plant population monitoring and seed collection, while agricultural scientists and farmers use it to plan everything from planting to pest management to crop harvest.

Since the 1950s, dedicated volunteers across the country have tracked the phenology of lilacs. Partnering with the USA National Phenology Network (USA-NPN), the Gardens monitors the phenology of many of the plants in the lilac garden. We also partner with Project BudBurst (PBB) to monitor 10 other easily recognizable species throughout the Gardens. These organizations support citizen science projects conducted by a network of people across the United States who monitor plants and report their data throughout the year. In addition to these projects in the Gardens, we have developed a Phenology Trail which currently includes three sites around Colorado, ready for use in spring of 2014. We will also be partnering with other organizations to expand our Trail to include more sites from which to collect phenology data and learn about native species and the diversity of habitats in our state.

We encourage you to help monitor plant phenology by making observations on one of the species the Gardens monitors or any one of the hundreds of species being monitored nationally. Become a citizen scientist by contributing your data with our partner organizations (National Phenology Network or Project Budburst) or through their mobile apps.

National Phenology Network 

Project BudBurst