Living things respond to their environment. Response to stimuli is an important characteristic of life. Anything that causes a living organism to react is called a stimulus (plural is stimuli) Stimuli can be external or internal. For instance, if you feel like going to the bathroom, it is an internal stimulus that is controlled by the brain.
Planting leafy green vegetables is easy, but itâs all in the timing. Knowing when to plant greens (such as spinach, kale, and lettuce) depends on your climate and if the leaf vegetables are heat- or cold-tolerant. Greens grow year-round in areas with mild summers and winters, such as the West Coast. For most other areas, spring and fall are the best times to grow greens.
Those last few weeks of winter can be miserable for gardeners wishing to see a glimpse of green. An early spring garden has been the savior of many a winter sufferer. Among vegetables suited for early planting, potatoes, onions and lettuce are some of the mainstays. Early in, early out is the growing technique for these garden staples. Lettuce can be grown year-round in areas with warm, but not hot, summers.