Croup is also known as laryngotracheitis, a medical term that describes the inflammation of the trachea (windpipe) and larynx. Parainfluenza viruses are the typical root cause of the infection, but influenza (flu) and cold viruses may sometimes be responsible.
Harvest entire kale plants at 60 to 80 days after germination when they are full size and no longer growing larger. Gather the leaves of one kale plant upward and hold them in this position. Cut across the bottom of the plant, horizontally about 1 inch above ground level to harvest the entire plant for side dishes, main dishes, soups or stews. Place the plants in a container to transport them indoors for storage or use.
Plants grown from seed require 70 to 80 days from sowing to reach a mature size. The time of year and weather affects the harvest time. Kale grows best in cool weather when temperatures are below 80 degrees Fahrenheit and it can tolerate freezing, but the plant grows more slowly when its below 32 degrees.