As I mentioned earlier you can grow them in your fall or spring garden. Early spring, March, which should be able to last through the summer as the leaves grow back really fast once mature. By August they will probably be done and you will at this point need to stay on them. The summer heat and sun will start to really take their toll. So planting more seeds in September or October would work really well. When growing the plant, you will need to sow your seeds ¼ to ½ inch deep and 6 inches apart. When they grow to the point of touching each other, you then harvest the whole plant so that the space left between them is 18 inches. A margin of 3 feet between rows is advisable since they can grow over three feet tall, and has a pretty good sized umbrella. The space will now be sufficient for the plant to mature and the thinned plants can be used as food.
For an abundant harvest, maintaining sufficient soil moisture during summer is necessary and you need to control insects and disease causing pests. A method of harvesting that allows the younger leaves to develop continually for future use exists. You can harvest only the large leaves when the plant has reached a height of 10 to 12 inches to achieve the former. During the process of creating a wider space when the plants are between 6 to 10 inches tall, cutting the plant at ground level is necessary. The most common problems you might experience when growing collards are aphids and cabbageworms. I didn’t have any issues till the deep summer with mine, so again really need to look after them during the July-August months when ever bug in creation is out in full force.