Tropical Spinaches for Kona
In my ongoing effort to encourage growing edibles, I want spinach lovers to know about some
In my ongoing effort to encourage growing edibles, I want spinach lovers to know about some
varieties that will thrive in Kona.
True spinach (Spinacia oleracea) grows best in temperate climate gardens. Several tropical
spinaches grow very well here and can offer similar nutrition, flavors and uses. The low growing
Okinawan spinach, the vining Malabar spinach as well as ong choy or water spinach are all easy
to grow in our tropical climate.
Okinawan spinach (Gynura crepioides and Gynura bicolor) has two varieties; one with a totally
green leaf and another with leaves that have a purple underside. Both grow as spreading ground
covers that can mound to nearly two feet tall.
A member of the Chrysanthemum family (Asteraceae), Okinawan spinach is native to tropical
areas of countries that border the East and South China seas. This includes the southern
Japanese islands, like Okinawa, as well as Indonesia, China, Thailand, and Myanmar. In many
tropical locales it is grown as both a vegetable and a medicinal herb.
This spinach is fast growing, can tolerate heavy pruning at harvest and produces lots of nutritious
leaves. Rich in vitamin A, the leaves also contain protein, iron, potassium and calcium. Known
in many countries as “cholesterol spinach”, it reportedly helps lower cholesterol.
The plants are also used as an ornamental ground cover. Unpruned, they occasionally produce
attractive bright orange flowers. Pruning and trimming low to the ground encourages leaf rather
than flower production.
The leaves are three to four inches long and quite tasty, especially when young. Raw leaves are
crisp, chewy and succulent, with a refreshing, mildly nutty and slightly bitter taste. Chopped into
bite-sized bits they can add bold flavor and a colorful addition to a salad. Okinawa spinach can
also be blended into juices or smoothies or used in tea. Though both the green and purple
varieties grow well here, I find the leaves with the purple undersides a bit tastier.
The leaves and shoot tips of this spinach can be lightly cooked making them soft and almost
slippery. Care should be taken, however as overcooking can make them a little slimy. Steamed,
solo they can be served as a side dish. They are also a great addition to stews, soups and stir-
fries or mixed with other vegetables.
Okinawa spinach is easy to propagate from cuttings that can be rooted in water or planted in
moist soil with most of the leaves removed. Plants can be grown in full sun or partial shade.
They require little maintenance other than pruning for size control. They are resistant to most
diseases and pests, somewhat drought tolerant, and will thrive in our warm climate.
Water spinach, known widely as the Asian green ong choy is a low growing plant. A member
of the Morning Glory family (Convolvulaceae), it produces a flower similar in appearance to
morning glories. Botanically, Ipomoea aquatica is in the Ipomoea genus, and a close relative of
the sweet potato, Ipomoea batatas.
High soil moisture is beneficial to the water spinach’s growth. In fact, it grows well and can
become somewhat invasive in rivers and swamps. Planting it in raised beds or other confined
areas is advised.
Harvesting is done by removing the whole plant. Cuttings from harvested plants will produce
new plants quickly, so successive planting will keep you continually supplied. It will thrive in
full sun as well as partial shade and will produce edible leaves in less than two months from
planting. Keeping the soil moist will encourage your ong choy to thrive.
The green leaves are arrow shaped and can grow to six inches long. They have a mild flavor that
some describe as grassy with nutty undertones. The raw leaves are slightly crunchy and can
enhance a salad. Both the tender shoots and leaves as well as the stems can also be cooked. The
stems are hollow and add flavor to a dish as they soak up the cooking liquid. The leaves are
tasty when steamed and topped with oyster sauce or stir fried with garlic. They can also be
cooked into soups or added to curries.
It is best to remove ong choy flower buds when they appear. This will prevent flowering and
eventual seed production. The “labyrinth” seeds are filled with air pockets and like the hollow
stems can float to other suitable habitats and become invasive.
The plants are seldom attractive to pests or diseases, especially when harvested young. To
encourage leaf production, you can fertilize lightly with a high nitrogen organic product
containing fish meal, blood meal, feather meal or composted manures.
Malabar spinach is another green leafy vegetable that is well suited to tropical climates like
ours. A member of the small Basellaceae family, the Bassella alba has green leaves while the
Bassella rubra has reddish leaves and purple stems.
The plant is native to India but is grown in moist lowlands throughout the tropics. The leaves
definitely resemble spinach but this plant grows as a vine and needs a trellis or other means of
support. It is different in that it thrives in tropical climates.
Malabar spinach will grow in partial shade but actually prefers a full sun exposure in a hot,
humid environment. Keeping the soil constantly moist will help prevent flowering, that can
cause the leaves to turn bitter.
Used very much like spinach, the leaves have a juicy crisp flavor with hints of citrus and black
pepper. Mixed with other greens it is a flavorful addition to a salad. When cooked, it tastes very
much like spinach and can be used similarly. In India, it is often cooked with chilies, onion and
mustard oil. Malabar spinach doesn’t wilt as rapidly as regular spinach and is also a good
addition to soups, stir-fries and curries.
You can propagate this spinach easily from cuttings. It does also produce seeds. Scarifying the
hard seed coating with sandpaper or a nail clipper to hasten germination, which can take up to
thirty days.
Malabar spinach leaves have the best flavor when they are young. Though the stems of Malabar
spinach are edible, they get tough as they age. If they are too tough to eat, simply put them in the
soil to root and make a new plant.
This is a relatively easy plant to maintain. It grows as a vine. Grown in rich, moist soil with
good support for the vines, it will produce lots of edible leaves. Harvest the leaves and stems
when they are young for the best eating and to control the size of the plant
Malabar spinach attracts very few serious pests or diseases and needs very little fertilizer. Using
a small amount of a high nitrogen product will keep her producing lots of leaves for your eating
pleasure.
For those of us who enjoy the flavor and texture and many uses of spinach, these three offer
better gardening success here in the tropics. Grow all three greens to add a variety of color as
well as the texture and taste of spinach to a variety of dishes.
Gardening Events
Saturday: “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
prepared to practice social distancing. Volunteers can help with garden maintenance and are
invited to bring a brown bag lunch. Water and snacks provided. Visit the website
www.amygreenwell.garden/get-involved/volunteer-1/ and sign up for the weekly email for more
information on work days.
Monday, March 6: “Tropical Fruits with Ken Love” from 5 to 7 p.m. at the Kea’au
Community Center, 16-186 Pili Mua Street in Kea’au. Free event offering light refreshments
and networking opportunities. Presented by the Hilo County Farm Bureau and the East Hawaii
Chapter of Hawaii Tropical Fruit Growers. For more information contact
hilocountyfarmbureau@gmail.com.
Tuesday, March 7: “Coffee Leaf Rust Research and Management Update Webinar”
starting at 9 a.m. with pre-recorded presentations for 20-25 minutes each. Followed by live
Q&A session for about 35-45 minutes. Presenters from USDA ARS PBARC, HARC, and UH-
CTAHR will share information and updates about CLR research projects, field trials, and disease
management. Registration is required to receive the Zoom link. Contact Matt at (808) 322-0164
to register at least a day prior to the event. Contact Andrea at andreak@hawaii.edu, 808-322-
4892 or 415-604-1511 (text ok) for more information.
Farmer Direct Markets (check websites for the latest hours and online markets)
Wednesday: “Ho‘oulu Farmers Market” at Sheraton Kona Resort & Spa at Keauhou Bay
Saturday: “Keauhou Farmers Market” 8 a.m. to noon at Keauhou Shopping Center
Information on their online market: keauhoufarmersmarket.com/onlinemarket
“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 Honoka’a
Plant Advice Lines
Anytime: konamg@hawaii.edu
Tuesdays and Thursdays: 9 a.m. to noon at UH-CES in Kainaliu – 808-322-4893 or walk in
Mon., Tues. and Fri: 9 a.m. to noon at UH CES at Komohana in Hilo 981-5199 or himga@hawaii.edu
Diana Duff is a plant adviser, educator and consultant living part time in Kailua-Kona.