While most of the country is packing up its gardens, Arizona's low desert is just getting started. The heat has finally broken in Phoenix and Tucson, and the soil is still warm. That makes October one of the best months of the year to sow herbs.
The University of Arizona Cooperative Extension's October gardening guide for Pima County lists cilantro, dill, Mexican oregano, parsley, sage, rosemary and thyme as herbs to start from seed by mid-month, alongside cool-season vegetables like lettuce, carrots, spinach and kale. Valley gardener Angela Judd's October planting guide for the low desert agrees: cilantro and dill go straight into the ground from seed now, while tomatoes, peppers and cucumbers should wait for spring.
For homeschool families, that means fresh science is ready to plant right now. Here's a fun question to test: which seeds are the fastest to sprout, and why?
What your kids will learn
A germination race teaches the basics of plant biology and the scientific method at the same time.
Grades K–5
- Identify the parts of a seed: seed coat, embryo and stored food
- Describe what a seed needs to germinate: water, warmth and air
- Observe, draw and describe changes day by day
- Measure root growth with a ruler
Grades 6–12
- Explain germination physiology: water uptake (imbibition), enzyme activation and the first root (radicle) breaking through
- Write a hypothesis and set up a controlled experiment
- Record data and calculate germination rate
- Compare species and explain why some seeds sprout faster than others
Try it this week: the desert seed race
Use any herb or vegetable seeds you have. A packet of cilantro or dill from the store is a great start.
- Predict. Line up two or three kinds of seeds and have each child guess which will sprout first and which will be last. Bigger seeds? Smaller seeds? Write the guesses down.
- Look closely. Use a magnifying glass to compare size, shape and color. Fun fact: a cilantro "seed" is actually a tiny dry fruit that usually holds two seeds inside.
- Set up a fair test. For each kind of seed, fold 10 seeds into a damp (not dripping) paper towel and slip it into a labeled zip-top bag. Keep every bag in the same spot indoors, out of direct sun.
- Plant a pot outside too. Sow a few of the same seeds in a pot of moist potting mix on a patio that gets morning sun, and keep the soil damp. Now you can compare the bag with the soil.
- Check daily. Record the date each seed's first root appears and measure it. Some herbs, like cilantro and dill, can take a week or more, so patience is part of the experiment.
- Calculate and graph. Count how many of the 10 seeds sprouted to get a germination rate, for example 7 out of 10 = 70%. Graph the days to sprout for each kind of seed and compare the results to the predictions.
When seedlings in the pot have a few true leaves, your kids can keep caring for them all winter and start snipping homegrown herbs.
Make it a mystery. The Surprise Herb or Vegetable Seed Germination Science Kit adds a detective twist. Each kit includes one seed packet we choose from 50 popular varieties, 16 herbs (like cilantro, dill, parsley, basil and thyme) and 34 vegetables (like lettuce, carrots, radishes and kale). Kids get to work out what they're growing from the seeds' shape, size and color, then confirm it as the plant grows. It comes with K–5 curriculum and observation worksheets, emailed after purchase, including a daily observation log and a root-length chart. Most varieties sprout in about 3–14 days.
Add a speedy sprinter. Sunflowers make the perfect comparison seed. The Sunflower Seed Germination Science Kit includes 10 sunflower seeds, absorbent germination paper and a resealable pouch, so kids can watch the seed coat split and the first root appear indoors, usually within 2–5 days. You choose K–5 or 6–12 curriculum and worksheets at checkout. That's a nice option for older students who want a lab report template and germination-rate math.
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. Members share progress photos, ask questions and troubleshoot experiments together.
Post your mystery seed guess before it sprouts, then reveal the answer when the leaves give it away. Arizona kids are planting in the middle of fall, while families in West Virginia and Arkansas are heading into frost season. Comparing notes across those climates is a science lesson of its own.
Start your desert seed race
- Surprise Herb or Vegetable Seed Germination Science Kit – $15.00. A mystery seed packet with K–5 curriculum and worksheets.
- Sunflower Seed Germination Science Kit – $25.00. A fast-sprouting seed lab with K–5 or 6–12 curriculum and worksheets.
The desert's best growing season is here. Plant a few seeds this week and let your kids find out what's inside.
