How Pollinator Corridors Work

A pollinator corridor is a connected chain of habitat patches that allows bees, butterflies, and other pollinators to move through a landscape. In cities, these corridors are fragmented — but residential gardens can fill the gaps.

The Stepping-Stone Model

Ecologists describe urban pollinator habitat as “stepping stones.” Unlike a continuous forest corridor, pollinators in cities hop between small patches of habitat: a wildflower garden here, a boulevard planting there, a native hedge across the street. Each patch doesn't need to be large — it just needs to be close enough for pollinators to reach.

Most native bees forage within 200-500 metres of their nest. Butterflies can travel further, but still rely on regular nectar stops. This means that gardens within 500 metres of each other can form a functional corridor — even if they're separated by roads, lawns, and parking lots.

Why Backyards Matter

In Canadian cities, residential land makes up roughly 40% of urban area. That's more than all parks and conservation areas combined. If even a fraction of those backyards included native plants, the total habitat area would dwarf what public green spaces alone can provide.

The challenge is coordination. A single gardener can't create a corridor alone — it takes a network. That's why knowing what your neighbours grow matters as much as what you grow yourself.

How Hortus Maps Corridors

Hortus calculates corridor connections between gardens based on three factors:

• Distance — Gardens within 500m are “strong” connections, up to 1km is “moderate,” and up to 2km is “weak.” These thresholds reflect the foraging ranges of common native bees.
• Bloom overlap — Corridors are strongest when connected gardens bloom in the same months, providing continuous food along the route.
• Shared species — Gardens growing the same native species create particularly reliable habitat patches, since specialist pollinators can find their host plants at multiple stops.

The map view shows these connections as lines between garden markers. As more gardeners join, the network becomes visible — and you can see exactly where new gardens would fill gaps in the corridor.

Building a Stronger Corridor

Want to strengthen your neighbourhood's pollinator corridor? Here are three high-impact strategies:

1. Fill bloom gaps — Check your bloom calendar. If your neighbourhood has lots of summer flowers but nothing in early spring or late fall, add species like Wild Bergamot (Monarda fistulosa) for mid-summer or New England Aster (Symphyotrichum novae-angliae) for fall.
2. Grow what's nearby — Look at the map to see what your neighbours grow. Adding complementary species strengthens the link between your gardens.
3. Recruit a neighbour — The biggest improvement to any corridor is adding a new node. Share a few native seedlings with someone on your street and invite them to join Hortus.

From Data to Action

Every garden logged on Hortus adds a point to the corridor map. Over time, this data shows which neighbourhoods have connected habitat and where the gaps are. Researchers and conservation authorities can use this to target outreach, allocate resources, and measure the impact of native planting programs — all from data that gardeners create by simply using a tool they enjoy.