Water is big news in Arizona this week. NPR reported on Oct. 29, 2026 that the Central Arizona Project, the 336-mile system of canals, pipelines and pumping plants that carries Colorado River water to the Phoenix and Tucson areas, could see its allocation cut by 47% under a new federal plan. Arizona, Nevada and the CAP have challenged that plan, and Lake Mead and Lake Powell have fallen to record lows.
It's a lot for grown-ups to follow. But it also opens a great conversation with kids, because the same canal water reaches farms, cities and plenty of backyard gardens. And it lands right at the start of the low desert's best planting season.
So here's a question worth testing at home: how much water does a seed really need?
Why November is planting time in the low desert
While much of the country is putting gardens to bed, Arizona's low desert is just getting going. The University of Arizona Cooperative Extension's November gardening guide for Pima County suggests sowing beets, carrots, peas, onions, chard, spinach, kale, endive and turnips directly into the ground early in the month. It also notes that the first frost sometimes arrives in mid-to-late November, so it's smart to have frost cloth or old sheets ready.
That makes this the perfect week to plant, and to turn planting into real science.
What your kids will learn
Grades K–5
- What seeds need to sprout: water, air and warmth
- The plant life cycle: seed, sprout, plant, flower, fruit, seed
- How to measure water with spoons and cups, and keep a simple chart
- Why people in the desert try to use water wisely
Grades 6–12
- Designing a fair test with one independent variable (water) and a control
- Measuring germination rate and seedling height, then graphing the results
- Comparing how different growing media hold moisture
- Connecting a small experiment to a real public issue: water supply in a desert state
This week's activity: the Water Budget Sprout Test
You'll need three small cups or pots with drainage holes, potting soil, a measuring spoon, a ruler and a packet of fast cool-season seeds such as radish, beet or spinach.
- Predict. Ask each child: "Which cup will grow best: the one watered every day, every other day, or every third day?" Write the predictions down.
- Set up three identical cups. Same soil, same amount of soil, and the same number of seeds (5 per cup is easy to count), all planted at the same depth.
- Label them. Cup A: water every day. Cup B: every other day. Cup C: every third day.
- Use the same amount each time. Give 2 tablespoons of water on each watering day. Keep all three cups side by side in the same bright spot so light and temperature match.
- Keep a water budget. Every time you water, add it to a running total for that cup. By the end, kids will know exactly how much water each cup used.
- Observe daily. Record how many seeds have sprouted, the tallest seedling's height, and whether the soil feels wet, damp or dry when you touch the top.
- Compare after 10–14 days. Which cup sprouted first? Which seedlings look healthiest? Did the cup that used the most water actually grow the best? Then transplant the strongest seedlings into your garden bed.
Kids are often surprised by the answer. More water isn't always better, and soggy soil can leave roots short on air. That's a lesson desert gardeners learn fast.
Want to run the experiment with many different crops at once? Our best-selling Heirloom Vegetable Seed Science Collection includes 30 individually packaged heirloom varieties, about 5,000 non-GMO, open-pollinated seeds, plus germination supplies and grade-level curriculum and worksheets emailed after purchase. Varieties include Detroit Red Beets, Red Core Carrots, Long Standing Spinach, Mixed Green Lettuce and Green Sprouting Broccoli, so you'll have plenty of the same cool-season crops the Extension guide lists for November. Older students can design germination trials across plant families and learn how heirloom seeds are saved from one generation to the next.
To go deeper into how soil holds water, add the Soil Science Experiment Kit (4 Pots). It includes four 3-inch peat pots, traditional potting mix, coconut coir pellets and two fast-sprouting seed varieties. Kids plant side by side and compare how each growing medium performs, and the 6–12 curriculum has students compare structure, moisture retention and aeration.
Join the growing community
Every purchase includes an invitation to Aardvark's Seed Planting For Little Hands, our private support group for students and families using our kits. Share a photo of your three cups, post your water-budget totals, and compare notes with young growers from Phoenix to Tucson, and with families in West Virginia and Arkansas whose gardens are heading into winter while yours is just waking up.
Plant smart this November
Arizona's water story is still being written. Your kids can learn to grow food with care for every drop, starting this week.
- Heirloom Vegetable Seed Science Collection – $85.95 (Grades K–5 or 6–12)
- Soil Science Experiment Kit (4 Pots) – $39.90 (Grades K–5 or 6–12)
