What catches your eye about the flowers in your city? Perhaps it is their vibrant colours, their fragrance, or simply the beauty of a city in bloom. Flowers can brighten the entire urban landscape, bringing a sense of delicacy, wonder, and relief amid the stresses of daily life. For a long time, however, architects and landscape designers chose urban plants mainly for their appearance and how easy they are to maintain. But how do the tiny inhabitants of our cities, such as bees, butterflies, and pollinating flies, so often go unnoticed by our eyes, perceive these urban gardens? A recent study conducted across seven Italian cities and published in Landscape and Urban Planning revealed that ornamental plants can do far more than merely decorate our streets. Sometimes, they function as thousands of little restaurants scattered throughout the city, serving as vital stepping stones for urban biodiversity. To understand this, researchers surveyed 43 popular ornamental plant species and monitored thousands of insect visits. But not every pretty flower makes for a good restaurant! That was the researchers’ first major discovery: not all ornamental flowers cater to all pollinators. Species like Pyracantha koidzumii and Deutzia crenata were the biggest hits, drawing in the most customers by attracting both a massive quantity of insects and a rich diversity of different pollinator species. Other plants, such as Borago officinalis, attracted plenty of customers, but nearly all belonged to the exact same species. Meanwhile, flowers celebrated for their beauty, such as Viola lutea or Tagetes erecta, drew very few pollinator customers. Following these findings, a question naturally arises: why do insects prefer some plants over others? The answer lies in floral traits, namely the flower’s shape, size, and the type of reward it provides. Disk-shaped or open flowers are the clear favourites among bees and beetles. Because they are open, accessing food is straightforward for...