Growing degree-day facts for kids

Growing degree days (GDD), also called growing degree units (GDUs), are a clever way to measure how much heat plants and even some animals experience. Think of it like a special heat counter!

Farmers, gardeners, and people who study plants use GDD to guess when important things will happen. For example, they can predict when a flower will bloom, when an insect will wake up, or when a crop like corn or wheat will be ready to harvest. It helps them plan their work better.

What are Growing Degree Days?

Growing Degree Days (GDD) help us understand how quickly plants and cold-blooded animals grow and develop. Their growth depends a lot on temperature. The warmer it is, the faster they usually grow, up to a certain point.

How GDD are Calculated

To figure out GDD, scientists use a simple math formula. They look at the average temperature for a day.

The Base Temperature

Every plant or animal has a "base temperature." This is the lowest temperature at which it can start to grow or develop. Below this temperature, it basically stops growing. For example, corn might have a base temperature of 50°F (10°C).

Daily Calculation

Here's how it works for one day:

• First, find the highest temperature of the day.
• Then, find the lowest temperature of the day.
• Add these two temperatures together and divide by two to get the average daily temperature.
• Subtract the plant's base temperature from this average.
• The number you get is the GDD for that day!

If the average temperature is below the base temperature, the GDD for that day is zero. Plants don't get "credit" for cold days.

Why GDD are Important

GDD are a super useful tool for many reasons:

Predicting Plant Growth

• Harvest Time: Farmers use GDD to know exactly when their crops will be ready to pick. This helps them plan their harvesting schedule.
• Flowering: Gardeners can predict when their favorite flowers will bloom.
• Planting Dates: Knowing GDD helps decide the best time to plant seeds so they grow well.

Managing Pests

• Insect Life Cycles: Many insects, like pests that harm crops, also develop based on temperature. GDD can predict when insect eggs will hatch or when adult insects will appear.
• Pest Control: This helps farmers know the best time to use pest control methods, making them more effective.

Climate Change Studies

• Tracking Changes: Scientists use GDD to see how climate change might be affecting plant growth and farming seasons over many years.
• Future Planning: It helps them understand if growing seasons are getting longer or shorter in different areas.

Examples of GDD Use

Different plants need a certain number of GDD to reach maturity.

• Corn: A specific type of corn might need 2,500 GDD to be ready for harvest. Farmers track the daily GDD accumulation from planting until that number is reached.
• Wheat: Another crop, like wheat, will have its own GDD requirement for different stages of its life cycle, from sprouting to producing grain.
• Fruit Trees: GDD can help predict when fruit trees will blossom, which is important for pollination and fruit development.

By using Growing Degree Days, people can make smarter decisions about farming and gardening, helping to ensure healthy plants and good harvests.

See also

A friendly robot, ready to learn!

In Spanish: Suma térmica para niños