Annuals and Perennials in Iowa

Certain plants grow during specific times of the year and others do not. This is because plants store energy that allows them to go dormant in the winter while others can’t store enough energy so they die off when the environment changes around them. The plants that are able to adapt to their environment and come back each year are called perennials. Those that don’t come back when their environment changes are called annuals. Changing your environment is important for many plants in a place like Iowa because there are many different seasons and weather types. 

Driving Question

What is the difference between annuals and perennials?

Probing Questions

• What plants do you see during only one season but grow back every year? 
• Do you think if we changed our environment plants in the annual family would be able to live throughout the whole year? What kind of changes would we need to make to make this occur?
• How do you think environmental changes impact which plants grow back and which do not? 
• As you look at the pictures of a sunflower at different times of the year, do you think it is an annual or perennial plant? Why? 

Classroom Suggestion

Students could:

• Give students an example of a plant that comes back every year (hostas) and one that does not (sunflower). Have them come up with what they notice are similar and what they notice are different about each plant (this may be difficult to do). Have them work in groups to come up with reasons why they think the one plant comes back and the other does not. 
• Have students draw random plants that grow in Iowa from a hat. Ask them to research the plant and find out whether or not it grows back each year. Ask them what allows their plant to grow back each year or what causes it to die. Put them in groups or have them share as a whole class the results that they found. Compare the results as a full group to see if they can come up with a good reason for why some plants come back and some plants die and do not come back.
• Show students pictures from different times of the year of a plant that grows back each year. Have them write down as many questions as they can think of within a one-minute time frame. Then show them pictures throughout the year of a plant that doesn’t grow back each year. Again, give them a minute to write as many questions as they can. Split the class into 5-7 groups and have them go through the questions they came up with and think of answers to each question. Then work through the questions and share their answers as a class.

Related Resource

• Iowa DNR: This article gives a description of how plants come back if they die in the winter. It is relevant to Iowa plants. 
• Science Learning Hub: This article talks about the plant life cycle and different types of plants that grow. 
• Illinois Extension: This article gives examples of why plants bloom at different times of the year.