Kale requires a well fertilized soil so make sure to enrich the soil with compost at least a month before sowing. Kale loves cool, moist soil so be sure to keep the soil well watered from germination through the growing season.
Kales is heavy feeder so make sure to fertilize the plant with organic fertilizer. You can also use the fish fertilizer which gives an extra kick. Also, make sure to keep all the weeds away from the kale plant.
You can start harvesting kale leaves as soon as they are large enough to be used in a salad. Use knife or scissors to cut the plant an inch above the ground. Kale leaves when stored in refrigerator are good for two weeks to about a month.