Readers Amy Kimura of Manoa and K.T. of Nanakuli both wrote in asking about how to grow uala, or sweet potatoes.
Uala is easy to grow in Hawaii, and is ono to eat and very versatile in recipes. The tubers are ono and nutritional, and so are the shoots and leaves, which require minimal cooking. In fact, I mainly grow them for the lau, or leaves. My simplest recipe is to pick some leaves, rinse, chop and saute with garlic and olive oil. I then add eggs and cook it all up for a tasty, nutritious breakfast.
I also make a version of kandaba, an Okinawan soup. As Hilda Kaneshiro says, cook up some leaves, add whatever veggies and protein you have, plus broth, and make some tasty, easy soup. The whole family will love it and be healthy.
Hawaiians of old extensively cultivated uala, and it kept them healthy and strong. Uala can grow in drier places with poorer soil than our favorite Hawaiian starch kalo, or taro.
Sweet potatoes are not to be confused with potatoes. They are in the morning glory family, Convolvulaceae, and are known to scientists as Ipomoea batatas. They are originally from tropical America, and people have carried them all around the world to grow in their food gardens.
Most plants that came by canoe to Hawaii are native to Southeast Asia, but uala is a mystery, being native to tropical America.
They are rich in fiber and beta carotene. The vitamin C and E in uala protect your eyes and other body parts. The fiber makes you feel fuller, so you eat less. The good fiber in uala helps lower your blood sugar by slowing the rate at which food is converted into glucose and absorbed into the bloodstream. Uala is also rich in potassium and in folate and vitamin B6.
In old Hawaii there may have been up to 230 varieties. We still have a lot of varieties in Hawaii today. The flesh can be pale yellow, bright orange or purple. These bright colors indicate a nutritional powerhouse for human health.
IN THE GARDEN
The easiest way to grow sweet potatoes is to buy some and let them kind of sit and sprout on your counter.
Chop them up into 2- to 3-inch pieces and plant the sprouting tubers in a full-sun part of your garden in a mound of well-drained soil. You can plant them in rows if you want a lot of them.
You can also grow them from cuttings. Select healthy, vigorous cuttings with three to six leaves. Chop off the lower leaves and cut the upper leaves in half. Plant the cuttings in a pot or in the ground and water daily.
AS A POTTED PLANT
Uala can be grown in a big pot. You can harvest the leaves and shoots after a few months and harvest the tubers in about seven months and again over time.
Make sure the soil drains well and the pot is in as sunny a location as possible. A pot is perfect on an apartment lanai.
THE PUKA POHAKU METHOD
One creative and easy harvesting method used in old Hawaii can be replicated in your garden. Make a rock tower with good soil in the middle. Stack sweet potato sprouts inside. Craft it so some rocks can be pulled out without collapsing the tower. Hence you have a bunch of productive uala growing in a small vertical space.
It’s easy to harvest a potato or two without digging up all of the soil. It can also be an attractive garden feature.
SLOPE STABILIZER
You can make a ground cover of uala to prevent erosion, and it doesn’t need much water. You can periodically harvest the shoots or tubers, or just leave it to grow. Different varieties have variously colored and shaped leaves, so you could also plant several varieties in a pattern to give a more creative landscape-design look to your garden.
Heidi Bornhorst is a sustainable landscape consultant specializing in native, xeric and edible gardens. Reach her at heidibornhorst@gmail.com.
