Hawai'i Gardens
Lavender flowers cascade from sandpaper vine
By Heidi Bornhorst
You can tell how this plant gets its common name when you gently run your fingers over the leaves. They are very rough and feel like sandpaper.
Deborah Booker • The Honolulu Advertiser
The parts of the plant that will initially attract you, though, are the lovely flowers in a unique shade of blue/violet/lavender. There is also a less common white form, which has a clean and striking appearance.
Sandpaper vine may feel rough but the pretty flowers are likely to attract people. The vine looks good on an arbor or trellis.
This is an old-fashioned plant, so you won't find it in every garden, or amid the usual plants you see at garden stores these days. When you do find it, be happy and try to find a good home for it in your garden.
Scientists call it Petrea volubilis and place it in the Verbenaceae family. It is native to Mexico, Central America and the Caribbean.
The pretty flowers are a rare color in the plant world. The flowers emerge at the tips of the branches in clusters, which can be a foot long. The flower petals, or corolla, are lavender and look almost like a true violet was inserted into the flower. These flowers don't last too long on the plant, however — just a day or two before they fall out. The calyx, or basal part of the flower, lives longer and it is very noticeable.
This "vine" can also be trimmed as a hedge or bush. You can let it grow to its full height (as much as 35 feet) by providing a strong and sturdy support for it. It looks great on an arbor or trellis. If your garden is small, yet you want some shade and garden color, consider vines on trellises or espalier the vines along a wall. This is a creative way to get the most out of our small Hawaiian gardening spaces and to have some color, fragrance and shade in the garden.
Sandpaper vine looks great on a slope, too; I'd like to see them along the freeway where the plants could sprawl down the hill and display their strikingly colored flowers. It is a somewhat uncommon plant in Hawai'i today, but it is one we should grow and plant in the right spot in our gardens.
If you want to see a sandpaper vine, here's where to find them. There is a white form on the Vineyard Boulevard fence at Foster Botanical Garden. One of my favorites is a purple one that quietly cascades down the slope of H-1 freeway along School Street. It is between Nu'uanu Avenue and the School Street on-ramp, near the Liliu'okalani Botanical Garden, on the mauka side. Check out this lovely lavender cascade (but NOT when you're the driver).
Sandpaper vine is somewhat difficult to propagate, but it can be grown from cuttings. Ask your favorite landscape nursery to get or grow a plant for you.
Besides enjoying this plant in your garden, the somewhat paperlike flowers lend themselves to artistic craft projects. The flowers dry well and retain their unique color. Try them in a dried flower arrangement, for an elegant band for your papale (hat), or make pressed flower or oshibana cards from these different blossoms. You can also make a lei of the blossoms alone or in combination with other lei flowers.
When you need flowering color in the winter and spring, when less is in bloom in most Hawai'i gardens, think of the sandpaper vine. It is also a pretty good xeriscape, or less-thirsty garden plant, and is also fairly wind- and salt-tolerant. As with most flowering plants, give it full sun for maximum flowering enjoyment.
Heidi Bornhorst is director of Honolulu's botanical gardens — Foster, Lili'uokalani, Wahiawa, Koko Crater, Ho'omaluhia. Write to her care of The Advertiser Homestyle section, P.O. Box 3110, Honolulu, HI 96802. Or e-mail her at islandlife@honoluluadvertiser.com
