Is kale a perennial or annual plant?

The Kale's lifecycle is categorized as somewhat biennial and somewhat annual. Kale is a biennial plant but is most commonly grown by gardeners as if it were an annual plant because it bolts after its first year of growth. I have overwintered a Winterbor kale plant for 18 months while living in zone 8b and have consistently harvested from it before removing it and replanting it the following season. In colder climates such as zone 5, the frost will kill the plants, which is why people grow kale by sowing every spring.

Whether plants survive the winter or not is based on variety and protection. In zones 7-10, I provide a straw mulch around the crowns of plants like kale just before the first frost. The straw insulates the root system while plants re-sprout in spring (start regrowth). Leaves that have had frost damage naturally sweeten, and I accept this tradeoff because I want early spring additional harvested plants before replanting.

The concept of seed-saving makes kale a perennial undertaking. Allow one plant to bolt in its second year. Once the pods are dry and rattling, they can be harvested for the seeds. I have a Scarlet kale that cross-pollinated with my broccoli and created some strange hybrids. For best purity, isolate your varieties at least 1,000 feet apart.

Container gardening augments productivity. I am growing my Dwarf Blue Curled in 10-gallon pots, bringing them to the garage when we get freezing overnight temperatures. I can replicate biennial cycles without ground space. In dormancy, I do not water them often, as water is likely to rot the roots/underlying material. I give them full care again when air temps are above 40°F (4°C).

Read the full article: How to Grow Kale: Complete Planting and Harvesting Guide