In the face of declining populations of pollinators like bees and wasps, how can an urban garden non-profit grow more produce?

Schapiro Undergraduate Research Fellow Wyatt Richardson ’26 has spent his research hours in the sun at Shalom Farms this summer, in search of ways to attract a rich mix of pollinators to the non-profits’ Westwood Avenue farm. Along with Professor and Biology Department Chair Dr. Nick Ruppel, Richardson is seeking to measure the impact of companion plants in the gardens.

Shalom Farms distributes the food that it grows to communities where access to healthy food is limited, so crop yield is particularly important to their work. 

To help their crop production, Shalom Farms plants marigolds and sweet alyssum next to their tomatoes and peppers. These companion plants provide a variety of benefits. Nematodes in the soil are bad for tomatoes, but the marigolds are great at deterring them. Both flowers also attract predators, like parasitoid wasps, that keep away harmful insects, such as hornworms, from damaging the tomatoes.

“Through having those flowers in this space, we’re able to lower the amount of intervention that we need to do to prevent the tomato hornworm in the area,” said Amber Albee, Production Director for Shalom Farms’ Northside location. “You can create that natural ecosystem where the wasp is coming in and helping to lower the population of those hornworms.”

While the farm is already utilizing companion plants for their ability to deter threats, Richardson and Ruppel are studying the potential added benefit of boosting pollinator activity, and in turn yield. Richardson, a biology major with minors in chemistry and economics, has taken the lead on data collection, meticulously observing and documenting, both in person and through cameras, the pollinators—like honeybees and bumblebees—on the plants.

With the marigolds and sweet alyssum already in place, the duo is specifically studying if the addition of wildflowers would have a positive impact on pollinator abundance (total number of pollinators) and richness (variety of species of pollinators).

“Honeybees and bumblebees aren’t as plentiful to come by as they used to be in natural habitats,” Richardson explained. “Some businesses have attempted to solve this through commercial bee usage. They’ll partner with a business that breeds bees on an industrial level and artificially place those pollinators there to make up for the lack of abundance. That has its benefits for the farm in general, but it ends up worsening the depletion of natural wild bees.”

Being able to naturally attract these pollinators, and bypass the need for commercial bees, has both financial and sustainability benefits for farms. This is doubly so for urban gardens like Shalom Farms, where the number of habitable spaces for pollinators is much lower.

Ruppel explains that while tomatoes can self-pollinate, they can also benefit from bumblebees in a process called buzz pollination, which features “supersonic vibrations that knock the pollen out.”  Honeybees don’t have the ability to do buzz pollination, so attracting bumblebees is crucial.

So far, Richardson hasn’t seen many bumblebees on tomato plants, but has seen activity around the wildflowers on the property. While the lack of pollinators isn’t the result that Richardson and Ruppel hoped for,  it can be the exact kind of information to help Shalom Farms improve its yield over time

“At the end of the summer, if Wyatt’s data says none of their tomatoes have pollinators on them, or the companion plants aren’t attracting pollinators that are useful for the tomatoes, and same with the peppers, it’s still useful information,” Ruppel said. “Just knowing that beneficial pollinators are found locally offers so much potential for future management.”