Seed shopping season is here in the Valley. The Great American Seed Up returns to North Phoenix Baptist Church (5757 N. Central Ave.) on Friday, November 6, from 3:30 to 7:30 p.m., and Saturday, November 7, from 9 a.m. to 2 p.m. Green Living Magazine lists it as free, with bulk seeds for more than 100 climate-appropriate vegetable varieties. Check the organizer's site before you go in case details change.
The timing is perfect. Fall and winter are prime growing season in Arizona's low desert, when cool-season crops thrive and summer's heat is finally behind us. But every Arizona gardener learns the same lesson sooner or later: great seeds can still struggle in the wrong soil. Our desert ground is often sandy, rocky or packed hard with caliche, and it behaves very differently from the bagged mix at the garden center.
So before those new seed packets get planted, give your kids a real scientist's job: figure out what your soil is made of, and which growing medium seeds like best.
Source: Green Living Magazine, Green Scenes: November 2026
What your kids will learn
Grades K–5
- What soil is, and how different growing media look and feel
- What makes a test "fair": changing only one thing at a time
- How to observe and compare seeds growing side by side
- How to record results with drawings and simple charts
Grades 6–12
- Soil composition: sand, silt, clay and organic matter
- Comparing growing media by structure, moisture retention and aeration
- Identifying independent, dependent and controlled variables
- Measuring germination speed, plant height and root development, then graphing results and drawing evidence-based conclusions
This week's activity: the desert soil detective test
You can do this one with a scoop of backyard dirt and things from your kitchen. No purchase needed.
You'll need: a clear plastic jar or bottle with a tight lid, a small garden trowel, water, a teaspoon of dish soap, two disposable cups, a pencil, a measuring cup, a timer, a bag of potting mix (if you have one) and a notebook.
- Collect a sample. With an adult, dig up about one cup of soil from where you plan to garden. Pick out rocks, roots and bits of gravel.
- Feel it first. Rub a pinch of damp soil between your fingers. Gritty means sand, silky means silt, sticky means clay. Write down your guess about what's inside.
- Shake it up. Fill the jar about one-third with soil, add water until it's nearly full, add the dish soap, tighten the lid and shake hard for two minutes.
- Watch the layers form. Set the jar down and don't touch it. Sand settles to the bottom within a minute, silt settles over the next few hours, and clay can take a day or more. Mark each layer on the jar with tape and measure it.
- Run a drainage race. An adult pokes three small holes in the bottom of each cup with a pencil. Fill one cup with backyard soil and one with potting mix, then pour half a cup of water into each over a sink. Time how long until the dripping stops.
- Compare and conclude. Which held more water? Which drained fast? Ask: "Which one would a thirsty seed want during a dry Arizona week?"
- Wash hands when you're done, and keep the jar to show the family.
Ready for the next step? Knowing your soil is half the story. The other half is seeing how real seeds respond. Our Soil Science Experiment Kit (4 Pots) puts the whole experiment in one box: four 3-inch peat pots, traditional potting mix, expandable coconut coir pellets and two seed varieties picked for fast germination. Kids plant the same seeds in different media and different seeds in the same medium, then track it all on side-by-side growth charts. Sprouting typically begins in 3–7 days. You'll also get a five-lesson curriculum and worksheets for K–5 or 6–12, emailed after purchase, including a lab report template with a graph for older students. No prior teaching experience is required.
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. Members share progress photos, ask questions, troubleshoot experiments and learn alongside other growers. Post a photo of your soil jar layers or your sprout chart, and see what kids in Arkansas and West Virginia are growing while Arizona enjoys its best planting weather of the year.
Find out what your seeds really want
The Soil Science Experiment Kit (4 Pots) is $39.90 and includes everything to plant and compare, plus grade-level curriculum and worksheets. It's a great way to turn this weekend's seed haul into a real science project.
