|What do seeds do if they are planted too shallow or too deep?|
|Seeds are amazing little packages. They have the embryo of an undeveloped plant, plus enough food (or energy) for that potential plant to sprout a stem up toward the sunlight, develop a couple of leaves, and begin the process of photosynthesis (converting sunlight to sugars). If a seed isn't planted deep enough, the growing roots can push the new plant right out of the soil. If a seed is planted too deeply it can run out of energy, or stored food, before it emerges into the sunshine to begin the process of photosynthesis.
Seed packets usually recommend the correct planting depth for the seeds they contain. A good rule of thumb is to plant a seed no deeper than twice its diameter.