Many adult gardeners are kids at heart: it never ceases to amaze them, no matter how many years they've tilled the soil, that beautiful, mature plants grow from insignificant-looking seeds. Few seeds present such an incredible surprise as Jack's, whose magic bean grew into a giant beanstalk; most are like Mr. McGregor's, whose vegetable seeds sprouted to produce predicable sizes of radishes, lettuce, French beans, parsley and cabbage. Whether tiny like a lettuce seed or huge like an avocado pit, each seed contains its own genetic code—it's hidden treasure—and most sprout into plants that look like their parents or the pictures on the packets they came in. This is a marvel of nature you can easily share with your children.
Experimenting with seeds
Some large seeds reveal secrets you can't see in smaller ones. Beans, for example, are great for showing kids how seeds are tiny embryos ready to burst out and grow. Simply, have your child place nine lima beans on a sheet of paper, three rows of three beans, to form a rectangle. Each bean should touch the ones next to it. Trace around the rectangle; then remove the beans and soak them in a jar of water overnight.
Next day, arrange them in the same way over the rectangular outline to see how much space they now cover. The water will have caused them to expand. Next, carefully peel off one bean's outer coating and separate the halves, called cotyledons, which feed the plant until its roots, stems and leaves grow to find nutrients in the soil, air and water. Using a magnifying glass, examine the curled embryo at the top of one cotyledon.
Another fun experiment is to make a simple seed viewer to watch a few beans germinate. Line the inside of a glass or clear plastic cup with dark construction paper; fill the centre with crumpled paper towels. Carefully slip four seeds between the construction paper and glass, then slowly pour water into the centre of the glass until the paper towels are saturated. To create darkness, loosely wrap another piece of construction paper around the outside of the glass. Place in a warm spot; keep the paper towels moist. Carefully lift the outside paper every day to see what's happening. In a few days you'll see the seed coats crack and roots emerge.
Once the leaves sprout, plant two of the seedlings in a pot filled with potting soil. Leave the other two between the paper and the glass and compare how soil and light affect growth in contrast to dark and soilless conditions.