For quite a while, I have been encouraging people to grow more edible plants. We import nearly ninety percent of our food and we could be growing lots of it in our backyards or on our lanais. So, this month I’m going to talk about one of my favorite edibles that can also serve as an attractive ornamental plant. That would be kale. Kale is easy to grow and can be consumed in many ways, making it a plant I always have in my garden.
My flavor favorite is the lacinato kale which carries the botanical name Brassica oleracea var. palmifolia. It is also known as Tuscan and dinosaur kale. The latter being a name referring to its bumpy leaves, reminiscent to some of reptilian skin. This kale has a long tradition in Italian cuisine, especially in recipes from Tuscany. Hence that moniker.
Lacinato kale leaves grow on a thick stem that can grow to over two feet tall in ideal conditions. The mature leaves can be nearly a foot long with a sturdy mid-rib which holds them aloft but also allows some leaves to curve a bit at the end. The straplike leaves are usually harvested from the bottom of the stem which leaves the remainder of the plant resembling a small palm tree.
Though some kale varieties have a slightly bitter taste when eaten raw, lacinato has a sweeter flavor that can be enhanced by chopping it fine and massaging the cut leaves with a little olive oil and lemon juice. This makes a tasty and highly nutritious salad green. Yum.
Botanists seem to agree that kale likely originated in the Eastern Mediterranean region, later crossing with other Brassica species that were being cultivated nearby. The history of these plants as domestic crops is recorded during Greek and Roman times, but may have been cultivated even earlier. Some historical records indicate that around the fifth century BC, what is now known as kale, was being grown and consumed in many parts of the world.
Botanically, all kales are in the Brassicaceae family which includes some well-known food crops. Most kales are in the oleracea genus that also includes cabbage, broccoli, Brussels sprouts, cauliflower and collard greens. Each is distinguished by a separate cultivar name. The word oleracea means “vegetable/herbal” in Latin and identifies all of these as edible plants.
A kale known as Brassica oleracea var. sabellica has attractive curly leaves. Several colorful variants of sabellica are also available. Kale ‘Redbor” is a variety with deep red color and similarly curly leaves.
The red Russian, Brassica napus var. pabularia, can also add color and texture to your garden. It has reddish stems and a flat gray-green leaf. Though in a separate genus, it has similar flavor, growing preferences and uses as other kales. All of these make attractive additions to any garden and can be consumed in many ways.
Kales appear in a variety of recipes. Raw kale can add vitamins and minerals to a salad or smoothie. When cooked, kale does lose some of its nutritional value but it is delicious when steamed, sauteed or added to a soup or stew. You can even bake kale into crispy chips; providing a nice, low-calorie crunch.
With all this going for edible kale, it is good to know that the edible varieties can also serve as interesting ornamentals. Lots of truly ornamental kales are also available that will add color and interest to your garden.
Though these ornamentals can be eaten, they are somewhat bitter and best suited to enhancing the beauty of your garden. Many different cultivars are available. Varieties like ‘Chidori’ have purple leaves with extremely curly leaf margins and white or deep magenta centers. The ‘Nagoya’ varieties have round kale leaves that are heavily crinkled with tight rosette centers that vary in color from fuchsia to lavender to greenish yellow and creamy white. Combining these with more edible varieties can make a kale garden into an eye-catching display.
Though you may find some kale varieties in garden centers or nurseries, the unusual varieties are more available as seeds. You can direct seed in a garden if you protect the seedlings from birds and mollusks. Seeding in starter trays and transplanting once they are four or more inches tall may be the safest way to start your kale. If you are growing for salads, you may want to plant seeds close to one another and harvest the crop early as baby kale. Replanting every few weeks will keep you supplied with a continuous harvest of tender baby greens for a long time.
Kale is usually considered a cool weather crop. Fall is a good time to start growing kale here. Though it will grow in full sun in our summer heat, it will likely do better and be lest bitter if grown in partial shade during hot weather. It will do best in fertile soil that is high in organic matter and drains well. Not drought tolerant, most kale varieties will respond well to regular watering. Organic fertilizers high in nitrogen will help increase leaf production.
Though you need to watch out for snail and slug damage as well as the green caterpillar of the white cabbage moth, other insects and diseases do not usually attack kale plants.
Kale contains an impressive list of vitamins and minerals including vitamins A, C, and K as well as manganese, fiber, calcium, iron and potassium. It also contains phyto-chemicals that provide many health benefits. Kale also has the highest anti-oxidant properties of any fruit or vegetable.
Kale is easy to grow, highly productive in good growing conditions and has many uses. Whether you want to grow kale to harvest baby leaves for salads or to harvest mature leaves for soups and sautéing, now is a good time to get your kale garden going.
Gardening events
Saturdays: Work Day at Amy Greenwell Garden, from 9 a.m. to 12:30 p.m. Meet at the Garden Visitor Center across from the Manago Hotel in Captain Cook. Come with a mask and be prepared to practice social distancing. Volunteers can help with garden maintenance and are invited to bring a brown bag lunch. Water and snacks provided.
Now: CLR resistant coffee trees available for pre-order. Ungrafted $10 / Grafted $15. Email Andrea at andreak@hawaii.edu to express interest in the Catimor hybrids. Not available for propagation purposes.
Save these dates:
Wednesday and Thursday, Sept. 11-12: Webinar on Coconut Rhinoceros Beetle, from 1 to 4:30 p.m. Go to bit.ly/CRBsyposium to register. Sponsored by Big Island Invasive Species Committee.
Saturday, Sept. 21: Kona Orchid Society Show &Sale, from 9 a.m. to 2 p.m. at the Makaeo County Pavilion at the Old Kona Airport State Recreation Center. Admission is $2. Early Bird Special is entry at 8 a.m. for $20 and includes a cup of coffee. Come meet local orchid growers and their lovely orchids.
Sunday, Sept. 22: The Annual Hamakua Harvest Festival, from 9 a.m. to 2 p.m. at 44-2600 Mamalahoa Hwy. Honoka‘a. A celebration of local agriculture including food, hula, fun and more.
Friday, Saturday and Sunday, Oct. 4-6: 34th Annual Hawaii Tropical Fruit Growers International Conference at the Maui Food Innovation Center and farm visits. Talk by Dr. Johathan Crane from the Tropical Research and Education Center at the University of Florida plus workshops. For more information, go to htfg.org.
Friday, Oct. 11: 10th Annual Landscape Maintenance Conference from 8 a.m. to 4 p.m. at the Westin Hapua beach Hotel on the Kahala Coast of Hawaii. The conference theme is Fire and Water.
Farmer direct markets
(Check websites for the latest hours and online markets)
Wednesday and Friday: Ho’oulu Farmers Market, 9 a.m. to 2 p.m. at Sheraton Kona Resort at Keauhou Bay
Saturday: Keauhou Farmers Market, 8 a.m. to noon at Keauhou Shopping Center; Kamuela Farmer’s Market, 7:30 a.m. to noon at Pukalani Stables; Waimea Town Market, 7:30 a.m. to noon at the Parker School in central Waimea; Waimea Homestead Farmers Market, from 7:30 a.m. to noon at the Waimea middle and elementary school playground.
Sunday: Pure Kona Green Market, 9 a.m. – 2 p.m. at Amy Greenwell Garden in Captain Cook; Hamakua Harvest, 9 a.m. to 2 p.m. at Hwy 19 and Mamane Street in Honokaa.
Plant advice lines
Anytime: konamg@hawaii.edu
Tuesdays and Thursdays: 9 a.m. to noon at UH-CES in Kainaliu: 322-4893 or walk in.
Mon., Tues. and Fri: 9 a.m. to noon at UH CES at Konohana in Hilo, 981-5199 or himga@hawaii.edu.
Diana Duff is a plant adviser, educator and consultant living part time in Kailua-Kona.