Loofah gourd aka Luffa is most commonly known for the 'loofah sponges' it produces, is used for cleaning and bathing. A loofah scrub is frequently used in saunas and is the preffered back scrubber of tree huggers, hippies and herbalists around the world. It is 100% natural and works well leaving no carbon foot print.
Loofah is actually an edible gourd known as Luffa aegyptiaca [although a few other varieties do exist]. It resembles a cucumber in shape and size. It is sweet and tasty and used in many International cuisines. It is cooked with meats, in stir fries, and so forth. From a North American point it has qualities comparable to Okra and Squash. Loofah is also a tasty addition to salads served cold and sliced like a cucumber.
The seeds can be processed and eaten just like pumpkin or sunflower seeds and the flowers can be made into fritters similar to Pumpkin Blossom Fritters.
The loofah sponges develop as the vegan meat melts away, leaving behind only the abrasive exoskeleton. Once it reaches this point it is no longer edible.
Growing Loofah Gourds
Seeds Healthy mature loofah seeds resemble watermelon seeds, they are dark and hard. Immature seeds are lighter in color and have a softer shell.
Loofah can be seeded directly into the ground in hardiness zones 7 or above. Below [north of] USDA zones 7 they should be started indoors and transplanted at an opportune time. Soil temperature should be in the ballpark of 70 degrees F or warmer. Plant 3 to 4 seeds per mound sown no more than 3/4 inch deep.
Trellising and Supports of Loofah Vines
Loofah is related to pumpkins, gourds and squash and grows in a similar fashion, on a vine. The vines frequently need to be supported by a fence or trellis. They can be grown as a sprawling vine along the ground, but IMO a trellis works best. The loofahs themselves are more rounded and less susceptible to disease and varmints when kept off the ground.
It differs from squash and gourds in some key areas. One major difference is that it needs a long growing season of 150 to 200 days of warm frost free weather.
The gourds can be up to 3 feet long on rare occasions, but average between 1/2 and 2 feet. Diameter increases exponentially, anywhere from 4 to 7 inches round. The vines can be upwards of 30 feet in length when left to their own devices but should be maintained at a more manageable length.
Soil, Mulch, Fertilizer
Soil - Well drained. Excessive moisture and over watering can cause root rot fungal diseases and overall poor growth.
Mulch lightly plants that are trellised. Plants that are permitted to sprawl on the ground will not need mulch as the foliage creates a living mulch.
So long as adequate organic material and compost is worked into the soil and the pH is within acceptable parameters, fertilizer should not be needed. If you feel that you must add fertilizer a blend lower in nitrogen than phosphorous and potassium is advisable. NPK Ratio of 1-2-2 or similar where the 2nd two digits representing Phosphorous and Potassium are double that of nitrogen.
The first fertilizer application, while the plant is still immature should be high phosphorous for root growth. Excessive phosphorus for too long can lead to premature flowering, a weaker plant later and a smaller harvest, so cut back on the phosphorous after the first application. Fertilizer applications, especially prior to fruit setting should have a higher potassium formulation for development of the set fruit.
Pinching Back Loofah for enhanced performance
For a higher quality produce, some growers will remove most of the first flowers to appear, these will be male flowers. Loofah produces male and female flowers. Male flowers are the first to appear followed by the females. The female flower has a small embryonic loofah gourd just below the blossoms. After the pollinating period, male flowers generally drop from the plant. Removing most of the male flowers, leaving just enough to ensure pollination enhances the quality of the harvest.
Another tactic used to enhance the quality and quantity of the loofah harvest is to prune off the first four lateral branches, pruning shears are advisable. As the season progresses, remove and discard any damaged fruit from the vine ASAP. If you suspect it is disease damage and not insect or critter created, do not put it in the compost heap as this will only serve to perpetuate the issue.
Harvest, Processing and Storage of Loofah
They ripen so far as being edible is concerned, in late summer. To reach full 'maturity' for use as a sponge they should left on the vine until the outer skin begins to dry and shrivel up. Thumping the luffa pod against a hard surface will help to loosen the skin and seeds a tad. The tip of the loofah can also be snipped off to shake out many of the seeds before peeling it. After harvesting and peeling away as much of the outer skin as possible wash the remaining outer skin away, a little scrubbing may be needed. What remains is a porous skeletal network. Cut up the loofah to desired sizes and remove the seeds, which are still edible.
Remove any remaining luffa gourds immediately following the first frost or they will rot. Harvested loofah sponges should be allowed to dry out completely, if the weather permits the sun is the best drying agent, if not they can be dried inside in a well ventilated area. Be certain they are completely dried as they are prone to mold and mildew if there is any moisture still in them. Properly dried luffas will store for years.
USDA Zones 6 to 11
Soil pH 6.0 to 6.8
Germination 7 - 14 days