Garden Game Theory: What Our Garden Can Teach Us About the Prisoner’s Dilemma

VISTA Gardens is extremely grateful to the Hillsborough County UF/IFAS Extension Service staff, especially Mary Bruce and Tia Silvasy, and all the Master Gardener volunteers, for their advice, support and expertise.

This article was submitted by Mary Bruce, Ornamental Horticultural Assistant, UF/IFAS Extension Hillsborough County, in conjunction with VISTA’s April 30, 2026, Plant Walk-Around that was arranged and coordinated by Education Chair, Nicole J.

Pictured below are Mary (in orange shirt), leaffooted bugs, and a leaf with leaffooted eggs plus a leaf miner trail. Also shown is an example of overwatering.

If you’ve ever wondered why your fellow gardeners sometimes make choices that… I’ll be nice… don’t exactly help anyone’s plants, you are in the wonderful world of “game theory.” You’ve probably heard the term before but are unclear what it really is. The same goes for Integrated Pest Management (IPM): we’ve all heard of it, but what exactly is it? Well, bear with me and I’m going to try to explain both at once. (If birds were garden pests, this truly would be trying to kill two birds with one IPM-approved stone instead of poison).

Game theory is the study of how people make decisions when their choices affect each other. It helps explain cooperation, competition, and why perfectly reasonable people sometimes make perfectly unreasonable choices. 

One of game theory’s most famous ideas is the Prisoner’s Dilemma, and believe it or not, it shows up in community gardens more often than weeds during the rainy season. The Prisoner’s Dilemma is a famous game-theory scenario where two individuals must choose between cooperating or acting selfishly. Even though cooperation gives the best overall result, each person is tempted to choose the “selfish” option, often leaving both worse off. It’s basically a fancy mathematical way of saying, “If we don’t work together, we all lose” or “united we stand, divided we fall.”

So, what’s the dilemma? Imagine two gardeners desperately needing to water their beds during a historic 25-year drought. Each has two options.  First sign up for a class at Extension to learn how to install efficient microirrigation with a timer and use only what’s needed (cooperate), or turn on the overhead sprinkler and indiscriminately let it soak everything in a 50-foot radius (defect).

Here’s how the prisoner’s dilemma plays out. If both use water wisely, everyone’s beds stay healthy with no swampy mulch, no diseases, no mosquito breeding grounds. If one leaves the overhead sprinkler running, they get quick watering, while others discover, split tomatoes, powdery mildew and slugs roaming every corner of the bed. If both leave sprinklers running, we get fungal outbreaks, run away soil, and an exorbitant bill from the water department that shuts the whole garden operation down.

So why do we do this? Because just turning on the sprinkler is quicker and easier. Pest control works the same way, the fast, easy individual fix often causes long-term trouble for everyone.

This exact pattern of the prisoner’s dilemma shows up in Integrated Pest Management and gardening a lot. So put down the torches and pitchforks and understand it’s just nature, it’s a game and all of nature is playing it.

Integrated Pest Management, IPM, is a holistic approach that uses cultural, mechanical, biological, and, only as a last resort, chemical methods to manage pests. It focuses on keeping plants healthy, preventing outbreaks, and reducing pesticide use.

Key principles include:

• Prevention first

• Regular monitoring

• Choosing the least harmful effective method

• Saving chemicals for last

Here is how the dilemma unfolds... If everyone uses gentle, sustainable methods, pests stay at a reasonable and manageable level. If only one gardener goes heavy on chemicals, pests drop fast for that gardener alone and increase for everyone else. Finally, if everyone goes heavy on chemicals, pests evolve, develop resistance and suddenly nobody wins. Not even the tomatoes.

It’s a tale as old as time and pests, yes, they’re players too. They “choose” (through evolution) whether to stay susceptible or become resistant. Overusing chemicals pushes them toward becoming tiny “super bugs.”  Meanwhile, beneficial insects try to keep balance, gardeners try (or forget) to coordinate, and the whole ecosystem becomes its own strategic board game.

Whether it’s gardener vs. pest in an evolutionary arms race or neighbor vs. neighbor managing whiteflies… the lesson is the same: cooperation beats going rogue every time.

The Prisoner’s Dilemma teaches that choosing what seems best for you alone, like over-spraying or ignoring IPM, can leave everyone worse off, including you. Gardens thrive when gardeners communicate, coordinate, and choose strategies that support the whole ecosystem for the long-term.

So, before you ride off into the sunset with a solo pest-control plan, remember even aphids are playing the game. We might as well play smarter.