While much of the country is pulling up its gardens for the winter, Arizona's low desert is just getting going. The University of Arizona Cooperative Extension's vegetable planting calendar for Maricopa County lists a long menu of crops to sow from seed in November, including beets, carrots, peas, radishes, spinach, kale, turnips, bok choy and green onions, plus broccoli, cabbage, cauliflower, chard and lettuce from seed or transplants (University of Arizona Cooperative Extension).
Desert families have been growing food through the cool season for a very long time. In Tucson, Mission Garden describes itself as a living agricultural museum of Sonoran Desert-adapted heritage fruit trees, with garden plots that trace the region's farming history from early agriculture and Hohokam and O'odham crops through Spanish, Mexican and Chinese gardens. It also has a youth garden, and its calendar lists a Family Game Day on Saturday, November 14 (Mission Garden).
So this is the moment to give your kids a garden of their own, and to turn it into a real science lab. One quick note for families in the high country: Flagstaff, Prescott and other high-elevation towns have a very different calendar, and November there is better suited to indoor seed experiments.
What your kids will learn
Grades K-5
- What plants need to grow: sunlight, water, soil and space
- How a seed sprouts, and how to spot roots, stems and leaves
- The plant life cycle: seed, sprout, plant, flower, fruit, seed
- How to plan a garden and record growth with drawings and simple charts
Grades 6-12
- Germination, transplanting and the full plant life cycle
- Calculating garden bed area and volume and designing a planting layout
- Designing a fair test, controlling variables and comparing germination rates
- Measuring and graphing plant growth over time, and how heirloom seeds carry traits from one generation to the next
This week's activity: the seed depth experiment
Every seed packet tells you how deep to plant. This activity lets your kids test whether it matters. All you need is a packet of radish seeds (they sprout fast), a sunny spot of garden soil or a large pot, a ruler and a notebook.
- Ask the question: does planting depth change how fast seeds come up, or whether they come up at all? Have each child write a prediction.
- Make three short rows. Use the ruler to make one furrow about 1/4 inch deep, one about 1/2 inch deep and one about 1 inch deep.
- Plant the same number of seeds in each row, say ten, spaced evenly. Cover them, and mark each row with a label.
- Keep everything else the same. Water all three rows the same amount at the same time. Explain that depth is the one thing you're changing (the independent variable), and everything else is held constant.
- Check every day. Record the date each seedling appears in each row. Desert sun and wind dry the soil surface quickly, so note how often you water.
- Count and compare. After about two weeks, count how many seeds came up in each row. Younger kids can draw a bar chart, and older kids can calculate a germination rate for each depth and write a short conclusion.
If you want this to become a full season of science instead of a single experiment, the Raised Garden Bed Plant Science Kit (6 × 3 × 1 ft) ($94.99) gives your kids their own outdoor lab. It includes a galvanized steel raised bed, five 3-inch peat pots with soil for starting seeds, and five different seed varieties, plus a grade-level curriculum and worksheets emailed after purchase: a garden planning map, a germination and growth tracking chart, and a results reflection for K-5 or a lab report template with graph for 6-12. One thing to plan for: filling the full bed takes about 18 cubic feet of garden soil, which isn't included.
To fill that bed with cool-season crops and a much bigger experiment, add the Heirloom Vegetable Seed Science Collection ($85.95). It has 30 heirloom vegetable varieties and around 5,000 non-GMO, open-pollinated seeds, including Detroit Red beets, Red Core carrots, Long Standing spinach, Green Sprouting broccoli and mixed lettuce, along with germination supplies and a curriculum on plant families, germination trials and seed saving.
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. After your order, request to join and we'll add you. Arizona kids have something fun to share this time of year: while families in West Virginia and Arkansas are moving their experiments indoors for the cold months, desert gardeners are just planting. Post your seed depth results and garden photos, and compare notes with young growers across all three states.
Plant your desert garden lab this month
November sowing in the low desert can mean fresh greens, radishes and carrots in the weeks and months ahead, and a whole season of data for your homeschool science notebook.
- Raised Garden Bed Plant Science Kit (6 × 3 × 1 ft) – Outdoor Garden Lab with Curriculum & Worksheets: $94.99, grades K-5 or 6-12
- Heirloom Vegetable Seed Science Collection – 30 Varieties, 5,000+ Seeds, with Curriculum & Worksheets: $85.95, grades K-5 or 6-12
