Luffa plants (Luffa aegyptiaca) are fun to grow and they make a great kid project in the garden. Although you can eat immature luffas as vegetables, most people grow them for sponges. They are grown like cucumbers – they need to trail up a structure, they need full sun, and they prefer plenty of soil moisture. You can start them from seed easily, either indoors under lights in April or outdoors in May after our last frost.
In the summer, luffas bloom yellow flowers, about 3 inches wide. The bees love them, which is good because you need the bees to pollinate the flowers in order to get the fruit. Like summer squash, there are male and female flowers. After pollination occurs, you will see little green fruit behind female flowers.
Luffas take 90 to 120 days to mature. For sponges, pick them when the skin is yellow or brown, the fruit is lighter in weight, and the fruit “gives” if you lightly squeeze it. Cut it off the vine with about 2 inches of vine. Let it dry further (bring inside the home where it is dryer and warmer than outside). Remove the skin and remove the seeds. If it hard to remove the skin, soak in warm water for about 20 minutes. Save the seeds for next year.
The interior has a fibrous structure that is stiff when dry but softens and becomes flexible when wet. It makes an excellent scrubber for pots and barbeque grills, as well as for exfoliating the skin. You will find that your luffa is not white like store-bought luffas. The natural color is tan and may look “dirty.” Store-bought ones are bleached. You can bleach your luffas in 1 part bleach to 10 parts water for about 20 to 30 minutes.
When you start to use your luffa often in the shower, make sure it is allowed to dry between showers so it does not harbor bacteria or mold. Tie a string on one end and allow it to hang outside of the shower stall.
They can be put in the dishwasher or boiled in water to clean them. If you think they are no longer useable you can put them in the compost pile.
Luffa seeds are easy to purchase through seed companies. I rarely see luffa plants for sale at the local nurseries in this area. Try growing your own sponges this year, they are as easy as growing cucumbers!
They grow like cucumbers because they are so closely related. I think of them as squash, which are also related, but the vines seem to be more like those of cucumbers.
They are in the cucumber family, grow like cucumbers but with less disease problems.