Rooftop garden of bee watcher Reynold Weidenaar

Rooftop gardens are very popular these days. These elevated oases can range from complete green roofs planted with a single plant such as sedum, to more diverse “meadow-like” landscapes with native wildflowers. Even relatively small rooftop planting efforts may have a positive impact on urban pollinators.  Earlier this summer, NYC Bee Watcher Richard Weidenaar incorporated a few bee-attracting plants to his 22nd floor rooftop. A few weeks ago he wrote the following:

“We had a stand of gayfeathers – 5 plants with total 45 flowering stalks – which ALWAYS had bumble bees as long as it wasn’t too windy. Contrary to the idea that bees are less active after 3 PM, the activity would build to a maximum number of bees around 7 PM (location is sunny from 1:30 to 7:30). We like to watch bees when we have dinner out there.

When the gayfeathers fade at the end of July, we have lavatera plants that open up with 50-60 blossoms each. Their white flowers are horn-shaped, like morning glories. When longhorn bees arrive in August, they go crazy inside these blossoms, rolling around the stamens like Chubby Checker on steroids. We see them coated all over with white pollen. The longhorn bees also like morning glories, but these flowers close up after a few hours.

This year we saw our last bees on our terrace around the beginning of September. We know they are still around elsewhere — we saw thousands at a nature preserve near Carmel. One plant that especially attracted bees there (longhorn, bumble, and honey) was the garlic chive. It looks like it will do all right in the wind, which is a constant presence up here. We just bought some seeds and will plant them next year. The bees will have to share their garlic chives with us, though, as these are very good sautéed or stir-fried with tofu.”

Given that roughly 30% of Manhattan is buildings, rooftop gardening could make a big difference for pollinators in NYC (in addition to providing free rooftop entertainment!).

Rooftop “Pollinator box” - has six of the seven Great Pollinator Project flowers. Photo by Reynold Weidenaar.