Despite the common misconception, the luffa sponge in your bath didn’t come
from the sea — it grew on a tropical vine that’s related to the cucumber.
When they’re young, luffa gourds resemble zucchini,
and they can be prepared the same way. If left to mature, they get big — sometimes as
much as three feet long — and their insides turn spongy but tough. Luffa has been made
into everything from industrial filters to shock absorbers, fabric and even building materials.
Humans have used luffa for so long that researchers haven’t yet
pinpointed its precise origin. But it was most likely domesticated in tropical Asia,
possibly India. It reached China around 600 AD and spread to Europe in the Middle Ages.
In the 1890s, Japanese farmers began producing luffa for industrial uses,
including as filters for diesel and steam ship engines. The U.S. Navy was Japan’s best
customer for luffa sponges — until the attack on Pearl Harbor during World War
II disrupted trade. After trying — and failing — to grow luffa in Florida and California,
the U.S. turned to growers in Latin America to satisfy the navy’s need for them. It was such an
important wartime commodity that selling luffa for cosmetic or other non-war-related uses was
illegal. In Latin America, “la estropajo,” as luffa is known, is still grown and appreciated.
For all of its incredible material uses, it’s easy to overlook the luffa gourd’s
culinary uses — and that’s a shame, because the immature fruit is delicious. As a member
of the cucurbit family, its long vines produce both male and female flowers.
The ovaries of female blooms grow into a fruit that is quite similar to cucumber or
zucchini. For eating, it’s best to pick when the fruit is under eight inches long.
Over the years, many southern gardeners visiting Baker Creek have asked about an
old-timey heirloom called “vining okra” that they remember seeing in their grandmothers’ gardens.
True okra is a member of the hibiscus family and doesn’t have a vining habit.
Vining okra is Luffa acutangula, a luffa type that has pronounced ridges, and the immature
fruit really does resemble okra. In steamy Gulf Coast states like Texas and Florida,
vining okra was often grown up an exterior wall
in the days before air conditioning. It worked: the vines could reduce the inside
temperature of a typical house by 10 degrees, according to historian David Shields. The
immature fruit was also dipped in batter and fried for mealtime.
The rough fibers of mature luffa fruit have long made an amazing scrub sponge for cleaning pots
and pans. And somewhere along the way, people started scrubbing themselves with it. It may
be that the Japanese tradition of Kanpu masatsu (a dry towel rubbing technique)
inspired the “friction bath.” This health and beauty fad took off in 19th century America,
when doctors advocated vigorous scrubbing to draw toxins out of the body. Women were
particular fans of the practice, and luffas were an ideal substitute for the stiff-bristled
“flesh brushes” or “Turkish mittens,” usually made from mohair.
Though it is a tropical, cold-sensitive vine, gardeners in most climates can grow luffa gourd
to some degree. Luffas need a frost-free window of about three and a half months
in order to mature. So northern gardeners can plan accordingly, knowing that the gourds might
not mature fully before first frost. You’ll want to give luffa vines a place to climb,
like an arbor or fence. Pollinators love luffa blooms. And if you’re growing luffa to eat,
be sure to check them often, because the fruit blends right in with the fast-growing vines!