Tyler’s Research on Containerized Vegetable Gardens

Today, Tyler successfully defended his undergraduate research thesis, entitled ‘Invest in Vegetables: A Cost and Benefit Analysis of Container Grown Roma Tomatoes (Solanum lycopersicum cv. ‘Roma’) and Italian Basil (Ocimum basilicum cv. ‘Italian’)‘.

A student in jeans and a long sleeved shirt, wearing a mask, stands in the middle of his containerized tomato garden research plot.
Tyler Spofford, in the middle of his containerized garden research plot, in the summer of 2020.

His research was inspired by the rush to vegetable gardening, that many households made during the start of the COVID-19 pandemic. Research has shown that there are many benefits to vegetable gardening, including social, emotional, physical, and financial. However, those in rental housing, or otherwise without easy access to land, were largely locked out of accessing these benefits.

Although previous research has shown that in-ground and raised bed vegetable gardening can yield positive economic benefits, to date, no studies (that we know of) have quantified the financial costs and benefits of growing vegetables in containers. Tyler thus set up a system of 5-gallon and 3-gallon bucket gardens, planted with Roma tomatoes, or Roma tomatoes plus Italian basil. He kept careful track of the cost of materials, and the time he spent gardening. He also kept careful track of the harvest he pulled off of each container.

Over the course of his study, he successfully learned about and fought back Septoria leaf spot, and blossom end rot. We learned that Roma tomatoes, in particular, are susceptible to blossom end rot. On top of these horticultural plant problems, Tyler’s research was abruptly halted by the late summer wildfires of 2020, that made air quality unsafe for him and others to continue their work, outdoors.

Despite these challenges, he was able to glean enough data from his project, to share some interesting findings:

  • None of the containers netted a positive economic benefit, in the first year of gardening, largely because the cost of materials outweighed the financial benefits of the harvest.
  • If the project were continued into year two, he projects that he would have had a positive financial outcome for the tomatoes grown with basil, in the 5-gallon containers.
  • Across the course of the season, he only spent 30 minutes tending to each container. Because he had few garden maintenance tasks, the time invested in container gardens was minimal. This is an important finding, for folks who may shy away from gardening because of lack of time.
  • As expected, the 5-gallon containers yielded more than the 3-gallon tomatoes. The 3-gallon containers stunted plant growth too much, to recommend them as a viable container gardening system. [As a side note, we were given the 3-gallon containers, for free, which is why we included them in the study.]
  • The fair market value of Roma tomatoes was fairly low (~$1.00 per pound). Thus, the net economic benefit of growing Roma tomatoes was also low. Basil, on the other hand, was a high value specialty crop that helped to raise the overall economic value of crops harvested from the buckets.

If you are interested in seeing Tyler’s thesis defense presentation (~30 minutes), you can do so, at the link below.

https://media.oregonstate.edu/id/1_8v2t4zd4?width=400&height=285&playerId=22119142

Tyler will be graduating in a few days, with a degree in BioResource Research from OSU! He’s worked in our lab group for two years, and has been an absolute joy to learn and work with. We wish him the very best on the next adventures that await him.

Garden Ecology Lab Research Update

COVID-19 has impacted our research in many different ways, including making it more difficult to find time to provide research updates on a regular basis. Despite the long silence, we have many projects up and running this summer! In fact, we’re launching four new projects, finishing up three long-term projects, and writing up another two projects.

In this blog post, I give a brief overview of the four new Garden Ecology Lab projects that launched this summer.

Microbiome of Garden Soils and Gardeners: Dr. Gwynne Mhuireach’s project has been spotlighted in a recent blog post and webinar. She has selected the 40 gardeners that will be included in her study: 20 high desert and 20 Willamette Valley gardeners, half of whom are organic and half of whom are conventional gardeners. Soon, these gardeners will be sending in their soil and skin swab samples. And then, the long process of analysis will begin.

She’s studying the microbe community in garden soils, and how those might differ according to garden region (Willamette Valley or high desert) and gardening practices (organic versus conventional soil managmeent). She’s also studying whether garden soil microbes transfer to gardeners’ skin during the act of gardening, and if so, how long those microbes persist on the skin.

Pollinators on Native Plants and Native Cultivars: Jen Hayes is well into the data collection phase of her first field season. She is working with undrgraduates Jay Stiller, Tyler Spofford, and Isabella Messer to: track flowering phenology, measure floral traits, observe pollinator visits to study plots, and collect pollinators so that they can later be curated and identified to species. Jen has written about her research project, in a past blog post. I’ve also set up a Flickr album to host photos from her study.

Native plant and nativar study site, at the Oak Creek Center for Urban Horticulture. A yarrow cultivar, ‘Salmon Beauty’, can be seen in the foreground. Nemophila, Clarkia, and Escholzia cultivars can be seen in the background.

Jen’s field site is located at the Oak Creek Center for Urban Horticulture at OSU, which makes it so much easier for undergraduate student researchers to participate in this project. She samples pollinators on Tuesdays and Fridays. She takes 5-minute observations of pollinator visits on Mondays and Thursdays. In between, lots of time is spent weeding and watering plots, counting flowers, and measuring floral traits.

Cost / Benefit Analysis of Growing Edible Plants in Containers: Tyler Spofford is a new lab member, who is completing his undergraduate degree in the BioResource Research program at OSU. He is working to develop a ‘budget’ for growing food in low-cost containers. I’ve summarized this ‘budget’ data for growing food in standard vegetable gardens, but no data yet exists (that I can find) for containerized vegetable gardens. Tyler is growing 40 tomato plants across two sizes of containers (3 gallons and 5 gallons), as single plants and in combination with basil. He’s keeping track of all of the costs (both money and time spent to grow food). When he harvests food, he’ll weigh his harvest, and track the economic benefit of his efforts, and how container size and planting configuration (one or two crops per container) influences harvest. I’ve set up a Flickr album for his study, to host project photos.

Tyler’s project grew out of my concern that, even though 18,000+ people enrolled in a free, online vegetable gardening course (over 40,000, at last count) ~ that the people who might be most at risk for food insecurity may not be benefitting from Extension Master Gardener resources and information. Tyler’s project is one component of a larger effort to develop more support for renters who might want to grow their own food.

Bucket gardens, on the day that the tomatoes were planted into 5-gallon BiMart buckets. We tried to keep all materials and plants low cost and easily accessible. Photo Credit: Tyler Spofford.

Below is an excerpt from a concept paper I’m writing on the topic:

We know that the COVID-19 pandemic is exerting stress on multiple pressure points related to the economic and food security of U.S. households: more people are in need of food aid and more people are concerned about food access. The U.S. has a long history of gardening in times of national emergency (e.g. Victory Garden of WW I and WWI II, ‘recession gardens’ of 2008). The benefits of gardening as a tool of economic security and resilience are well-established. However, research suggests that these benefits are largely restricted to homeowners. Currently, most state and local laws afford no legal right to renters who want to grow their own food. Community gardens might offer renters opportunities to grow their own food, except that these gardens are often associated with gentrification. To promote public health in the face of economic and health risks of COVID-19 and future pandemics, it is critical to support the food gardening efforts of the most vulnerable. Those in rental housing have been found to be most vulnerable to food insecurity, as well as the food and economic insecurity associated with natural disasters.

Pollinators on Buddleja Cultivars: Cara Still is studying how breeding butterfly bush (Buddleja davidii cultivars) for sterilty impacts the pollinator community that visits Buddleja blossoms. Buddleja davidii and some fertile varieties of this plant are considered noxious weeds in Oregon, and many other places. Normally, noxious weed status would make it illegal to sell or trade butterfly bush in Oregon. However, the Oregon Department of Agriculture allows exceptions for non-sterile cultivars and interspecific hybrids.

Buddleja ‘Buzz Velvet’ (I suspect that plant breeders have a lot of fun, naming new cultivars)

Cara is studying whether or not the plants that are allowed for sale, under the exceptions, still pose a risk of invasion. Our group is working with Cara to document the abundance and diversity of pollinators that visit eight fertile Buddleja cultivars with 16 cultivars that have been bred for sterility.

When I was initially approached to participate in this project, I thought that it should be obvious that sterile cultivars would not attract pollinators. Afterall, sterile cultivars don’t produce pollen, or produce very little pollen. Without pollen, I doubted that bees would visit the plants. But, it is possible that sterile plants would still produce nectar. And, many pollinators ~ such as butterflies and moths ~ visit plants to consume nectar, rather than pollen.

The more I looked into the literature, I realized that no one has yet studied how breeding for sterility might affect a plant’s attractiveness to pollinators. Would sterile forms of butterfly bush no longer attract butterflies? Would sterile varieties attract syrphid flies that visit blossoms for nectar, and not pollen? We’ll let you know what we find, in about a two years. In the meantime, you may want to visit the Flickr album of photos I set up for Cara’s study.