Although kale is perennial, it is usually only grown as an annual. In the following, you will find out why this is the case and how you can grow your kale perennial.
Kale flowers in the second year
Kale is biennial
Kale is usually biennial. You can read about this on your seed packet. However, it is often only grown once a year. The reason for this is simple: kale is very starchy during the warm season and therefore tastes bitter. Only in the cold season (not only when there is frost!) does it form less bitter substances, but still glucose, so that it tastes sweeter and milder. The harvest time begins in October and usually ends in February at the latest. Therefore, kale is practically useless from May to October and also takes up space that can be used for other plants.
Another problem is that kale belongs to the cruciferous family, which, like other heavy feeders, requires special crop rotation. For example, after planting any type of cabbage, the bed must recover for three years before you can plant cabbage again. If you leave the cabbage for two years, you practically "lose" a year, during which you can hardly use the cabbage anyway.
Harvest kale in the second winter
Although kale is considered a biennial, it can only be harvested in the first winter. The following summer, it will flower and then die, because like all plants, kale's sole purpose is to reproduce.
The flower of the kale
However, if you leave your kale in the bed over the summer, it will bloom a beautiful, bright yellow flower with the four petals typical of cruciferous plants. After flowering, the kale then forms seeds that you can collect and use for sowing next year. But be careful: do not sow in the same place!