As cities continue to grow at pace, natural habitats are increasingly displaced. Today, over 56% of the world’s population lives in urban areas, a figure expected to rise to 68% by 2050 (UN, 2018). This rapid urbanisation brings with it the challenge – and opportunity – of reintegrating nature into our built environment.
Among the many species that can benefit from these efforts, solitary bees are among the most vital. As highly effective pollinators that don’t live in hives or colonies, solitary bees thrive in compact, quiet environments – making rooftops and terraces ideal spaces for them to nest and forage.
In this article, we’ll explore the lives of solitary bees, their value in urban ecosystems, and how green roof expert Dusty Gedge is helping cities – and rooftops – become havens for pollinators.
Table of Contents
What Are Solitary Bees?
Unlike honeybees or bumblebees, solitary bees do not live in colonies. Each female is self-sufficient—building, provisioning, and laying eggs in her own nest. This independence makes them remarkably suited to urban environments, where smaller, fragmented green spaces are often the norm.
Solitary bees include:
Mason bees (Osmia spp.)
Leafcutter bees (Megachile spp.)
Mining bees (Andrena spp.)
Key Characteristics
- Utilise natural cavities, hollow stems, or soil to create nests.
- Highly effective pollinators, often outperforming honeybees in certain contexts.
- Generally docile and pose minimal risk to humans.
Their independent nature and adaptability make solitary bees ideal candidates for urban environments, where traditional nesting sites may be scarce.
Solitary Bees on Urban Rooftops
Rooftops present a unique opportunity to mimic natural environments and offer vital resources for bees: nesting space, flowers for forage, and protection from ground-level disturbances.
Supporting Case Studies
London Green Roof Study
A study by the University of Cambridge found that green roofs featuring a variety of wildflowers and sedums support more diverse pollinator populations than monoculture sedum roofs. In London, researchers recorded 21 bee species across green rooftops, demonstrating the potential of even small urban spaces to enhance biodiversity.
St. Louis Rooftop Gardens
In the U.S., research from St. Louis University identified 38 bee species visiting rooftop farms, underscoring how rooftops—when properly designed—can support diverse bee communities year-round.
The Importance of Supporting Solitary Bees
Solitary bees are more than just beneficial—they are critical players in urban ecology, helping pollinate plants that contribute to food security, biodiversity, and the beauty of green spaces.
Biodiversity Enhancement
Supporting solitary bees increases urban biodiversity. Their presence supports food webs, enhances ecological resilience, and contributes to a more balanced environment.
Urban Pollination
Solitary bees are incredibly efficient pollinators, essential for fruit, vegetable, and flower production in city allotments, rooftop farms, and residential gardens.
Public Engagement & Education
Bee habitats can serve as educational tools, helping residents and visitors understand the value of pollinators and engage with sustainability firsthand.
Insights from Dusty Gedge
Dusty Gedge is a renowned advocate for urban biodiversity and the founder of Livingroofs.org. With decades of experience, Dusty has shaped policies, designs, and best practices that put pollinators and people at the heart of green infrastructure.
Key Contributions
- Promotes plant diversity on green roofs to attract a wide range of pollinators.
- Consulted on award-winning rooftop projects, ensuring ecological functionality.
- Former president of the European Federation of Green Roof and Wall Associations, helping embed green infrastructure into urban policy.
- Collaborated with RYNO to develop rooftop habitats tailored for solitary bees, ensuring systems are ecologically sound and technically robust.
Dusty’s advocacy has helped shift rooftops from overlooked surfaces to thriving ecological spaces.
Best Practices for Rooftop Bee Habitats
To make rooftops truly bee-friendly, consider the following:
Plant Diverse, Native Flora
Use plants that flower at different times throughout the year to ensure consistent food sources. Aim for a mix of nectar- and pollen-rich varieties.
Install and Maintain Bee Hotels
Use untreated wood or bamboo tubes with 2–10mm cavity sizes. Place hotels in sunny, sheltered areas and clean them annually to avoid disease.
Go Chemical-Free
Avoid pesticides and herbicides. These can be harmful not only to bees but to the broader rooftop ecosystem.
Implementing these simple strategies can help transform even the most compact spaces into thriving pollinator habitats.
Explore Our Bespoke Planter Systems
As cities continue to densify, rooftops provide some of the last available space to bring nature back into our urban fabric.
With insight from Dusty Gedge, our TerraSmart® Habitat Systems have been designed to support pollinators like solitary bees while meeting the structural and aesthetic needs of modern developments. From drainage to root containment, every detail has been considered to create habitats that look good and do good.
Get in touch with our team today—whether you’re an architect, landscape designer, or developer. Let’s reimagine rooftops as ecosystems. Together, we can create spaces where bees thrive, plants flourish, and cities breathe.
