Tips for Growing Luffa Gourds

The smaller one is 10 inches long.

Recently, a friend told me that she had picked up a packet of luffa seeds to grow this summer.  After having spent last summer struggling with my own luffa plants, I decided to do some more investigating about their cultivation.

Here is what I learned:

Luffas are in the same genus as squashes, namely, Curcurbita which also includes cucumbers and melons.

Luffas require a very long growing season.  Some sources cite as much as 150 to 200 days for some varieties. However, there are some that are ready in as little as 120 days under optimal growing conditions.

Luffas are edible as any other squash would be up until they get to be about 8 or 9 inches long.  Cook and eat as you would zucchini.

Luffas are vigorous growers and will climb just about any support.

Female Luffa Flower

While all of that is very interesting, here is what I learned last year on my own:
 
Luffas are divas.  If the conditions are not just exactly right, then they won't germinate, grow, flower, produce fruit or anything.  The seeds I planted last year in early May that finally lead to the flowers and fruits you see on this page took about six weeks to germinate and begin to grow.  I despaired of ever having any vines, much less flowers and fruits.

The soil temperature must be 70 F or greater or they just don't do a thing other than pump out stem and leaves.  It was nearly August before I had a viable female flower.  Yes, like other members of this family, the pollen is produced by one flower type and the ovary by the other.

Male luffa flowers on top, Tennessee Spinner gourds underneath.

The vines will be SWARMING with insects.  Mostly small, red ants who, it turns out, do most of the pollinating.  But mason bees, paper wasps, yellow jackets, honey bees, bumble bees and just about every kind of fly will be all over the flowers or, at least, where the flowers ought to be.  The ants are attracted to a sticky sap that oozes from the base of the leaf petioles.  The wasps are particularly attracted to the very young fruits.  No clue why that is so. Just be careful if you decide to examine your luffas on a sunny, summer afternoon.

Once your vine finally begins to set fruit, you will see numerous flowers and fruits pretty much all at once.  With any luck, you will have at least 50 days left in your growing season for the fruits to mature before frost kills the vines.

Luffas smell.  Some don't mind the smell, but I find it off-putting.  It will get on your hands like tomato vine smell does. Fortunately, it washes off a lot easier.

Luffas are indeed vigorous growers.  Given the chance, they will climb just about any suitable surface and BLOT OUT THE SUN.

After the first killing frost, pick all the gourds on the vines, except the most recent, and take them inside to dry.  In my case, about half of what I harvested was actually ready to be made into sponges.

The gourds are ready when the skin has dried and darkened and the gourds are very lightweight for their size. If you shake the gourds, you should hear the seeds rattling inside. Mine took about four weeks in the dry, forced-air heat of my laundry room to dry out. 

It's a fairly straighforward process to remove the husk and rinse the sponge until the water runs clear.  It is somewhat less simple to remove the numerous seeds inside the gourd.  I got out what I could by firmly smacking the gourd on the inside of a 5-gallon bucket.  There are still lots of seeds in my sponges and they don't seem to hurt anything.

In order to save yourself a lot of tense waiting and potential heartache, I recommend the following:

1. Do not grow luffas unless you have at least 120 days of growing season.  That's 120 days between last average frost in the spring and the first average frost in the fall.  My zone 5b garden in central Nebraska barely meets those requirements.
2. Before sowing the seeds, soak them in water for 24 hours to help soften the seed coat.  Then, nick the seed coat with a pen knife before planting to help the seeds germinate.  This is something I did not do last year because I did not do my homework first.
3. Make sure the soil is warm enough before you plant.  You may want to mulch the soil to help keep the heat in.  I am going to try starting some of the seeds indoors on a heat mat before transplanting outside.  You never know.
4. Provide a suitable support.  The gourds are big and heavy.  Although I did not have any problems with the vines being too weak to support the weight of the gourds, I could see it becoming a problem with an especially large fruit.  You may need to support the fruit with an old nylon stocking or a mesh bag (like those the Cuties come in).
5. Sit back and let nature take its course.  I tried sweet talking the flowers. I tried hand pollinating the flowers. I tried pleading with and standing watch over my flowers.  The silly vine will make fruit when it's darn good and ready and there really isn't anything to be done to hurry the process along as near as I can tell.

All in all, I really did enjoy growing my luffas last year.  So much so that I'm going to try again this year.  The vines are beautiful, the flowers are lovely and as a pollinator attractor, I'm not sure it can be beat.  So sit back and enjoy the vines.

Oh, and grow some birdhouse gourds, too.  Much, much easier. Trust me.