Kale is one of the plants I would love to grow in my container garden. I heard mixed information on how long kale grows and if it comes back every year. So I did my own research to find the answer to this question.
Kale does not come back every year because it’s a biennial plant. This means it will spend the first year developing roots and foliage. And the second year developing flowers and seeds. And then it will die. Most gardeners grow kale as an annual plant to harvest the foliage.
I’ve written some details about how long kale will grow in your garden and what you can do to get the most of growing kale so keep reading.
Is kale an annual, perennial, or biennial plant?
Kale is a biennial plant so let’s understand what this means. An annual plant is one that grows for one year, develops flowers, then fruits with seeds and dies. A lot of vegetables are annual plants such as spinach, lettuce, tomatoes, cucumbers, and cilantro.
A perennial plant is one that can grow for several years. It will continue producing leaves, flowers, and fruits year after year. The plant will not die unless it’s affected by pests, diseases, or lack of nutrients.
The perennial plant will eventually start losing its health and not grow as well as the previous years due to the nature of old age. There are many flowering plants that are perennials such as aster, daylily, lavender, hostas, and hibiscus.
If the perennials are growing in a climate that has freezing winters, the plant may go dormant and appear to be dead as the leaves fall away. The roots will still be alive and they will sprout new foliage when the next growing season arrives.
A biennial plant such as kale will grow for two years. The plant spends the first year growing its roots and leaves. And the plant spends the second year developing flowers, fruits, and seeds. The biennial plant dies after the second year. Kale, parsley, fennel, carrots, and shallots are some examples of biennial plants.
So you can grow kale for the first year and harvest the leaves for your salads and meals. If you live in a part of the country that is in zone 7 to 10, the kale plant will continue growing leaves for harvest even in the winter. If you live in an area with freezing winters, the kale will go dormant.
In the next spring, the kale plant will become active again. But instead of spending energy on growing leaves, it will start flowering and preparing to develop seed pods. Once the plant develops the seed pods it will wither and die. You can harvest the seeds and plant them to continue growing new kale for the next growing season.
What are some perennial varieties of kale?
If you really want to keep kale coming back year after year, you can choose to grow some perennial varieties. These are quite rare and some of them don’t even produce seed so you need to grow them from cuttings.
Walking Stick
This kale plant is known as the Walking Stick because it grows long, thick stalks. You can grow this perennial kale using seeds and it does well in the hardiness zone between 7 to 10.
You can cook the leaves of this kale plant but you need to remove and dispose of the stalks.
Kosmic
This is one of the perennial kale plants that you need to grow using cuttings. The plant will grow leaves for 5-6 years if you’re in a hardiness zone between 7 to 10.
Once the plant starts to die, you can just take a cutting and start growing a new one. So you can keep growing this kale variety for years to come.
Sea Kale
Another variety of perennial kale is the Sea Kale plant that can grow well in sandy soil. It’s another kale variety suitable for the hardiness zone between 7 to 10.
You can grow this kale variety from seeds but the germination rates can be quite low. So it’s best to plant a lot of seeds and then thin them out later after the seedlings germinate.
What is the best time to plant kale?
Kale is a cool-season plant which means it does well in a temperature between 55 to 75 degrees. The best time to start growing kale is just before the last date of frost. This is just a little bit before spring begins.
You can harvest the leaves through summer, fall, and winter unless the temperature goes too high and causes the plant to bolt producing flowers.
You can have a second planting in early fall as the temperature begins to drop. If you live in a region that falls in hardiness zones 7 to 10 you can continue growing kale even in the winter. You can keep harvesting the leaves till the plant bolts and produces flowers in the next spring.
If you live in a hardiness zone below 7, you can continue to harvest the leaves till the harsh winter will render the kale plant dormant.
How long can you harvest kale?
If you start growing kale in early spring, you can harvest it through summer, maybe, even fall and winter if you live in a hardiness zone between 7 to 10. If you started growing kale in early fall, you can harvest it through fall and winter. If you live in a climate that is colder, you can harvest the leaves till fall.
The best way to harvest kale is to cut off the mature leaves starting from the bottom of the plant and moving towards the top. You can throw away leaves that are diseased or yellow and pick the rest.
You can continue to harvest the leaves of the kale plant using the cut and come again method. This means you keep harvesting the mature leaves while leaving some of the young leaves on the plant. The plant will continue to grow more leaves as the young leaves keep maturing.
I would suggest using a clean pair of gardening pruners to clip the leaves from the plant. This helps keep the wound small that the plant can heal. It will prevent pests and diseases from attacking the plant.
It’s also good to harvest the leaves when the first frost hits the plant because they tend to become sweeter and crispier due to the frost.
The kale is a biennial plant that develops flowers and seeds in the second year of its growth. You can harvest the seeds from the pods and use them for growing a fresh batch of kale for the next year.
How to store harvested kale?
Storing fresh kale in the refrigerator
The easiest way to store the freshly harvested kale from your garden is in the refrigerator. This can help keep the kale fresh and crisp for one to two weeks.
- You need to first wash the harvested kale leaves with water.
- Dry the water from each leaf using a paper towel.
- You can then place the leaves in a ziplock bag that is airtight. Remove the excess air by pressing on the ziplock bag.
- You can add the leaves in a layered fashion by placing a paper towel between each leaf. The paper towel will help soak any moisture from the kale and keep it fresh.
- You can store the ziplock bag in the refrigerator at a place that is free from moisture or other vegetables.
- To use the kale leaves, you can remove the required amount from the bag and store the remaining leaves back in the refrigerator.
Storing frozen kale in the freezer
This method can help you store the freshly harvested kale for up to 8 months in your freezer. You can remove the required amount and use it in your smoothies as needed.
- Cut the stems off the harvested kale leaves.
- Boil the leaves for 1-2 minutes in water with a little salt added to it.
- When the leaves have turned bright green, take them out, and immediately place them in ice water. Keep them in the water till they cool down.
- Dry the kale leaves by using paper towels.
- Now place the leaves on a baking sheet and put it in a freezer for 1-2 hours.
- You can take the leaves out of the freezer and put them in a freezer bag. You can store this freezer bag in the freezer for up to 8 months.
Fact Checked, Written, and Published by Kevin Rodrigues
Kevin is the founder of Gardening Mentor, a website that aims to teach people to grow their own food in a limited space. As a self-taught gardener, Kevin has spent several years growing plants and creating gardening content on the website. He is certified in Home Horticulture and Organic Gardening from Oregon State University. He has a Post Graduate Diploma in Horticulture and Landscape Gardening from Mumbai University.
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