Grades: K-5; Subject Areas: Science. (2008) Nick visits a rain forest in the middle of a city. In this botanical garden, a microclimate has been created within the city, a huge greenhouse where no one has to worry about the weather. In the hot tropical, or arid areas, shade greenhouses promote plant growth. In our own home, we can grow tropical plants that would not grow in outside gardens in North America. The potted plants thrive because we have controlled their growing conditions. When Nick grows a terrarium with his young guests, they begin to understand how climate can be controlled to create sub-tropical conditions.