Plant a Journey North Test Garden!
Journey North students plant and observe tulip test gardens to track the arrival of spring. They observe and record when their own plants – and those in other school gardens across the Northern Hemisphere – emerge from the ground and bloom. As students track this one plant type, along with temperatures, day length, and other seasonal signs, they discover how different factors influence plant growth. This sets the stage for better understanding our changing climate.

Many Journey North lessons and Tulip Test Garden Updates help students explore these ideas. Here are some examples:

Students track plant growth. They notice and predict how tulips will respond to normals and extremes in temperature. What happens after a cold snap or week of warm weather? Older students graph daily temperatures and plant growth. They look for patterns in their data.

Students look at weather and climate maps. They explore whether the average temperatures in their region in a given week/month/season are “normal?” They ask, How could these temperature patterns affect the progress of spring (blooming of tulips)?

Students analyze long-term data. As they compare data from different years, they ask, Did spring move forward at the same rate each year? Did we notice any patterns? What might have caused differences? This is how scientists find clues about climate change. You can use long-term data from these sources:

Tulip Gardens


Why is this study important?
The information your students gather may help reveal evidence of climate change in the Northern Hemisphere. As we look at long-term data from Journey North sites, and share that data with scientists, we will look for patterns. Are tulips in different regions blooming earlier, on average, than they were 20 years ago? Does this tell us the climate is changing? If so, how could that affect other plants and livings things that depend on them?

We can only answer questions like these with long-term data from observation sites across the hemisphere. As scientists, we never know when we collect data how it might be useful to future scientists. (British gardeners kept records for more than 100 years on bloom times of certain flowers. This gave scientists some of the first evidence that the climate was, in fact, changing!)

As classroom scientists use tulips as tools for watching spring unfold, they are contributing to this wealth of information. What's more, they are laying the groundwork for being informed citizens who will need to understand — and make decisions about — challenging environmental issues!

Why Look at Plants?

As plants go through their life cycles, they reveal the effects of temperature, rainfall, sunshine, and other factors. Plants can’t move in response to environmental changes.* So a changing climate would likely affect the bloom times and health of many plant species. This, in turn, can have a ripple affect on other living things that depend on those plants for food, shelter, and more.

Why Tulips?
Journey North uses tulip plants because they are easy to use in a widespread experiment. They are also sensitive to temperature variations, particularly in the 3 to 4 weeks before blooming.

Tulips are not native to North America. Native plants are ideal indicators of climate change because such plants have adapted their life cycles over thousands or millions of years to a region’s climate. But no native plant species grows throughout the Northern Hemisphere, so tulips were selected because they can be grown by all participants.

* Individual plants can’t move in response to a warming climate. But scientists have discovered that, over time, the ranges of many plant species have slowly moved north or to higher altitudes.