Kale is more than just a trendy health food!
Kale is actually a type of non-heading cabbage. It is closely related to other brassicas like broccoli, cauliflower, and Brussel sprouts.
The reason many people think of kale as a healthier alternative to lettuce is that it’s packed with nutrients! Kale is high in vitamin C, vitamin K, potassium, and calcium.
Kale matures in a matter of weeks when started from seed or transplants! Just be sure to plant at least 2 seeds per hole if you’re starting kale indoors in early spring or summer.
How many kale seeds per hole you plant is only one factor in growing this healthy salad green! Keep reading to learn more:
Types Of Kale
There is more than one type of kale!
If you ask the average person to picture a leaf of kale, most would imagine curly-leaf kale. However, flat-leaf and Tuscan kale varieties are also incredibly popular.
But that just covers edible kale. Kale is also commonly grown as an ornamental.
Ornamental kale comes in many different colors and is popular as an autumn annual. While you can eat ornamental kale plants, they’re nowhere close to as appetizing as varieties bred for the vegetable garden!
How To Start Kale From Seed
Kale seeds can be started indoors or planted directly in the garden depending on your local climate and harvesting plan!
Sow kale seeds ¼ to ½ inch deep regardless of starting method. Use a standard seed-starting mix.
Keep the soil consistently moist (not soggy!) while you wait for the seeds to germinate and sprout. Germination can take up to 14 days.
After seedlings reach a couple of inches in height, thin weaker plants by snipping them at their bases.
Transplant seedlings by staggering or planting in rows spaced 16 inches apart.
When Is The Best Time To Plant Kale?
Kale is a cold-hardy vegetable that thrives in spring and fall. The heat of summer can affect kale’s growth and overall bitterness.
Soil temperature is crucial whether you’re sowing seeds indoors or directly into the ground. Kale seeds germinate best in soil between 45°F and 75°F.
For a spring harvest: Start kale seeds indoors at least 6 weeks before your area’s last frost date.
You can start direct-sowing or transplanting kale about a month before the last frost date. This will give the seedlings plenty of time to mature before daily temperatures rise.
For a fall or winter harvest: Plant seeds up to 12 weeks before your area’s first frost date.
Ensure the soil temperature is below 75°F before sowing kale seeds in later summer or fall. It may be necessary to start seeds indoors and transplant the seedlings when the temperature drops.
If you live in a cold climate, select a variety that matures quickly. If you’re in a mild climate, you can grow and harvest fall-planted kale well into winter!
Tips For Growing Kale In The Garden
Kale is a wonderful candidate for any garden! This leafy green thrives in containers and raised beds. You can even grow kale indoors if it has access to plenty of sunlight.
Kale requires 6 or more hours of sunlight per day. More sun typically results in kale that tastes better and has a more appetizing texture.
Strategically offering kale some shade during the hottest part of the day can delay bolting and the loss of flavor.
Plant kale in well-draining soil that contains lots of organic matter. Kale prefers slightly acidic soil.
The best way to prep your garden bed for kale is by incorporating aged compost into the existing soil. This will improve drainage and provide a heavy dose of nutrition.
Kale needs plenty of nitrogen to reach its full potential. Side-dress around kale plants with an appropriate fertilizer as needed.
Kale grows best in consistently moist soil. Adequate moisture also helps protect kale plants from excess heat and sun exposure.
Irrigate kale with 1 to 1 ½ inch of water per week. Adjust as needed for rain and extremely high temperatures.
Mulching around the base of kale plants will prevent moisture evaporation and keep the soil temperature low.
Kale can be harvested at maturity or when the leaves are only partially developed (also known as baby kale).
Many kale varieties will mature in as little as 50 days after sowing. Some types take up to 95 days to mature. Mature leaves will be about the size of an adult’s hand.
For baby kale, you can start harvesting leaves about 30 days after starting seeds.
No matter where your kale is in its growth, harvest the plant’s outer leaves first. These leaves are the oldest and largest.
New growth originates from the center of the plant. Avoid harvesting the central leaves until the kale has reached the end of its growing season. Ideally, your kale should always have at least 5 leaves for photosynthesis.
You can remove mature or baby kale leaves from the stalk by hand or with a pair of clean pruning scissors. Remove each leaf at the base where it connects to the kale plant’s main stem. Do not, however, cut into the stem itself.
Saving Kale Seeds For Future Years
Both edible and ornamental kale varieties are usually grown as annuals. But these plants are actually biennials!
Biennial plants complete their life cycles over the course of 2 years. Many popular vegetables are biennials, including onions, parsley, carrots, and other brassicas like broccoli and cabbage.
As a biennial, kale does not produce flowers or seeds until its second year. If you want to collect seeds from your garden, you’ll need to let some kale plants overwinter after their first year.
Most kale varieties can tolerate temperatures as low as 10°F. You can cover kale plants with a traditional hoop house for extra insulation.
In its second year, kale will start flowering shortly after the temperatures rise. You can still harvest leaves at this time. However, flowering tends to negatively affect kale’s flavor.
Kale flowers should be left alone until seed pods appear and the stalk fully dries out. This indicates that the seeds are mature and ready for harvest.
Don’t wait too long once your kale’s seed pods turn brown. The pods will break open on their own shortly after the seeds mature.
The easiest way to remove kale seeds from their pods is to place all of your collected seed heads in a paper bag and shake.
Store collected seeds in a paper envelope somewhere cool and dry.
Kale seeds usually remain viable for at least 4 years after collection!
How Many Kale Seeds Per Hole – Final Thoughts
Growing kale at home is a great way to add more leafy greens to your diet!
While ready-to-plant kale starters can be found at many greenhouses, this vegetable is incredibly easy to grow from seed. Kale can be direct-sowed in the garden or started in seed trays indoors.
Kale’s potential doesn’t end with more nutritious salads, either. You can also raise ornamental varieties for use in autumn planters and garden arrangements!