Arkansas grows more rice than any other state, and this fall the crop had a rough finish. In an Oct. 5 report from the University of Arkansas System Division of Agriculture, extension rice agronomist Jarrod Hardke described a fourth straight year of hot, dry harvest weather, with temperatures of 100-plus every day and 75 or higher at night. His summary: "The rice is cooking out in the field."
The heat dried the grain faster than farmers could harvest it, and overly dry rice turns brittle. Hardke says trials suggest planting a little later in spring may help, and he recommends spreading planting dates out.
That's real agricultural science happening right in your state, and it starts with a question your kids can test on the kitchen counter this week: does temperature change how fast a seed comes to life?
What your kids will learn
Grades K–5
- The parts of a seed: seed coat, embryo and stored food
- What a seed needs to sprout: water, warmth and air
- Making a prediction and checking it with real observations
- Measuring roots with a ruler and drawing daily changes
Grades 6–12
- Germination physiology: water uptake (imbibition), enzyme activation and the first root (radicle) emerging
- Writing a hypothesis and running a controlled experiment with temperature as the one changed variable
- Calculating germination rate and average root length
- Connecting lab results to farm decisions like planting dates
This week's activity: The seed temperature test
You'll need 15 large seeds of one kind (sunflower seeds are ideal), paper towels, three zip-top bags, a marker and a ruler. A thermometer is a bonus.
- Pick three spots. A cold spot (inside the refrigerator), a room-temperature spot (a kitchen shelf), and a warm spot (the top of the refrigerator or a sunny windowsill that stays warm, not hot). Never use an oven, stove or space heater.
- Set up the bags. Dampen three paper towels (damp, not dripping). Place 5 seeds on each, fold the towel over and slide each into a bag labeled Cold, Room or Warm.
- Keep everything else the same. Same seeds, same amount of water, same kind of bag. Only the temperature changes. That's what makes it a fair test.
- Predict. Have each child write down which bag will sprout first and why.
- Check daily. Look for the first tiny white root. Record the day each seed sprouts, and if you have a thermometer, note the temperature of each spot.
- Measure and compare. On day 5, measure the longest root in each bag. Younger kids can draw them side by side; older kids can calculate germination rate (sprouted ÷ planted × 100) and graph the results.
Discussion question: most seeds have a temperature range they like best. Too cold and they wait; too hot and they can struggle. How is that like the rice farmers deciding when to plant? Scientists at the Division of Agriculture answer questions like that the same way your kids just did: change one thing, keep the rest the same, and measure.
Make it easy: a ready-to-go seed lab
If you'd rather skip the scavenger hunt for supplies, our Sunflower Seed Germination Science Kit puts the seeds, materials and lessons in one box. Sunflower seeds typically sprout in 2–5 days, so kids see results fast.
- In the box: 10 sunflower seeds, absorbent germination paper and a resealable germination pouch
- Curriculum: 4 lessons for Grades K–5 or 6–12 (you choose at checkout), from seed anatomy to hypothesis, data collection and conclusions; emailed after purchase
- Worksheets: a daily observation log, a root-length measurement chart, and a reflection sheet or lab report template
Want to compare a second kind of seed? The Surprise Herb or Vegetable Seed Germination Science Kit includes one seed packet of our choosing from 50 popular herbs and vegetables, plus Grades K–5 curriculum and worksheets. Part of the fun is identifying the mystery seed by its shape, size and color, then seeing whether it sprouts faster or slower than the sunflowers. Most varieties sprout in about 3–14 days.
Join the growing community
Every kit purchase includes an invitation to Aardvark's Seed Planting For Little Hands, our private group for families using our kits. Post your cold-versus-warm results, share root photos, and see what young growers in Arkansas, West Virginia, Arizona and beyond discover. We'd love to know which bag won at your house.
Ready to start your seed lab?
Set up the test this weekend and your kids could be measuring roots by midweek.
