Plants need only good soil, water and sun to grow, but your favorite flora may be a bit pickier about bedding than you think. By collecting some organic composting from either your own compost heap or from a kind neighbor, you can compare a plant's growth in organic soil versus the growth of a plant potted in store-bought bagged soil. Set a plant in a pot with organic compost and set another of the same type in a pot of bagged potting soil. Water and tend to both plants in exactly the same way for one week. Document which of the plants grows bigger, or which plant has the healthiest leaves, stems and buds at the end of the week.
Clay comes from the earth and sustains plant life in the regions in which it can be found. Compared to soil, however, clay may not seem able to compete when it comes to growing flowers and plants. By obtaining a pot of natural clay earth and a pot of natural soil, you can perform an experiment to see which substrate would best suit the garden beds in your next planting project. Fill a pot with natural clay collected straight from the earth and a second pot with natural soil. Plant one of the same type of plant in each pot, then water and tend to them daily in the same way for a week. At week's end, document which of the two plants has grown not only larger, but also appears healthier in the leaves, stems and buds.
Many of the dunes lining the coast have plant growth of one kind or another -- typically long, wispy grasses seen in romantic paintings of the shore. If grasses and some other types of plants can naturally flourish along a sandy dune, you may wonder, can other types of plants exist in a naturally sandy soil or a store-brought sand? Obtain and fill two pots with sand -- one straight from a coastline, the other from a bag of "play sand" found at your local home improvement store. Plant one of the same type of plant in each pot, then water and tend to both plants in the same way for a week. After the week ends, document whether the plants have flourished, are struggling to survive or have perished during the experiment.
In all good scientific comparison experiments, you want to find the variable that surpasses all the other variables in the subject. When experimenting with plants and soil types, your goal will be the same. By putting sand, clay and soil to the test, you will be able to determine which substrate is the most ideal substrate with which to line your garden beds. Fill one pot with natural soil, a second pot with natural sand and a third pot with natural clay earth. Purchase three plants of the same type and plant one in each type of soil. Tend to these plants in exactly the same way for a week's time. After the week has ended, document which plant has grown the largest and has the healthiest stems, leaves and buds of the three.