Have you dreamed of growing your own luffa but don’t know where to start? Or, perhaps you’ve started seeds but couldn’t get the luffa to grow successfully to maturity? Luffa are notoriously difficult to grow in most regions of North America. But once you get a few insider tips for growing luffa successfully, you’ll significantly increase your chances. It isn’t too hard, it’s just about knowing what luffa like. Ok, it is a little hard. But what is gardening if not tackling the hard stuff?
Tips for Growing Luffa Successfully
Sections in this article:
- Germinating Luffa seeds
- Transplanting Luffa outdoors
- Soil and sun conditions
- Pollinating your Luffa
- Something for your Luffa to Climb on
- Harvesting your Luffa
Germinating Luffa Seeds
The first step to growing luffa is germinating the seeds. Unfortunately, no grower (that I’m aware of) sells luffa plants, because they are temperamental and do not like to be jostled around, as what happens during commercial growing and transportation. Fortunately, the germination part is not the most difficult part. Primarily, you need to make sure you are using brand new seeds.
If buying seeds, make sure you are purchasing from a reputable grower. If you’re getting the seeds from a store or nursery, make sure the seeds are this year’s seeds. Luffa seeds have a shorter shelf life than other vegetables. If you are getting the seeds from a neighbor or seed swap, make sure that you choose the largest, blackest seeds from the largest plants you can. This will increase your germination rate and give you strong plants. Fortunately, mature, healthy luffas produce many, many seeds, so neighbor growers don’t need to be stingy with them. Unless you have neighbors that are like, commercial luffa growers or something.
If you live in an area with a very long growing season, zone 9 with a warm spring or zone 10, you can start your seeds right outside in your garden. This is the best and easiest way to ensure success. You need a long growing season because outside planting is going to be very late. Luffa grow slowly, and you need the luffa to mature in warm weather. Wait until all chance of cold weather has passed. I’m talking overnight lows – it is best if the weather doesn’t dip below 60 degrees overnight – and 65 is even better. So this means WAIT to plant. Unless you are in Florida or Vegas, you will probably have to wait until mid June.
Alternatively, you can also start your seeds indoors. I’ve tried it both ways – and failed both ways. But I’ve succeeded both ways too. The hardest part when starting seeds indoors is the transplant process (I’ll cover that below). So if you possibly can, starting outdoors is better. But for many in the US, that just isn’t an option.
As I said, the germination is not the most difficult thing of all the difficult things around growing luffa. Germinate luffa like you would a pumpkin seed: soak it in water overnight and then plant it in a large-ish seed cell on a heat mat with good quality potting soil. Cover with plastic wrap. I really like the Burpee soft silicon seed cells because when transplanting, you don’t have to disturb the roots very much. Luffa HATE their roots being disturbed.
Once the leaves appear, move it VERY GENTLY to a larger pot. I keep them in a pot on the heat mat with grow lights until they have at least 5 leaves. You may have to transplant them one more time into another larger pot prior to when they are ready for the garden. Once they start showing a little vine I start acclimating the plant to natural sunlight. Just like a tomato plant. More on that below.
Transplanting Luffa Outdoors
The luffa will need to acclimatize to outside conditions. You can do this the same way that you would with tomatoes: for luffa that have been under grow lights, put them in the full sun for only 2 hours the first day. After the two hours, move them back to the grow lights for the remainder of the day. The next day you can put them out for no more than 4 hours – but you should check on them at hours 2 and 3 to make sure that they aren’t singeing or wilting. Move them in at the slightest sign of distress. Each day add one more hour until they can stay out side for at least 6 or 7 hours.
Luffa should take at least a week of hardening off – and I usually bring them indoors every night for a full two weeks, just to be sure. This year the overnight temperatures have been chillier than normal, so I’ve had to wait longer than usual to transplant, bringing each luffa out in the sun in the mornings and then back in every. single. night. Whew.
Once it is warm enough to plant in the garden, make sure the location (a) has a lot of direct sunlight and (b) is at the base of a strong trellis, like a cattle panel arch or similar. Tomato cages won’t be large enough. Wooden trellises probably won’t be strong enough. You’ve been warned.
When moving the luffa to its new location, try really hard not to jostle it or shake it out of the pot. And definitely do not remove any of the soil like you might for a pepper or tomato. Just move the luffa with the soil in tact to the new planting hole. I like to use bone meal and fishmeal in my hole for organic nutrients.
After transplanting, your beautiful luffa start is at its most vulnerable. This is where I have had the most challenges in the process. Cold nights, bugs, birds, and sun all could quickly kill your luffas, or at best, send them into a month-long coma, with no discernable growth.
If cold weather threatens, use a row cover, burlap, or some sort of plastic shelter to protect your luffa. A few days of cold weather will stop your luffa from growing for like, a month. Or maybe a year, at least that’s what it feels like. Sometimes I use a bright light (but not a heat lamp – that would burn) over the luffa if the nighttime temperatures drop. You can also use an outdoor Wi-Fi thermometer like a Govee to monitor the temperature of the luffa. This way you can adjust the light distance from the plant up or down to get just the right temperature.
The next most important thing is to not overwater your luffa once its in its new place in the garden. Anything new or different during this time of transition will shock – and possibly kill your luffa. Yep, no kidding.
Soil and Sun conditions
I always plant my luffa in rich soil mixed with compost. As I said above, I also add bone meal and fish meal to the planting hole to make sure the luffa has enough nitrogen as it grows. You can add about a half cup of each. As the luffa grows, you may need to top dress with fertilizer – monitor your plant to see how they are growing. Luffa take a long time to mature, and you want to be sure they are growing consistently.
The most important thing I can say about the water is…. be consistent. If you water your plants more often, then do that all season long for the luffa, as long as you are using well-draining soil and it is drying out sufficiently. You don’t want wet roots. If you keep your beds on the drier side, then do that. But in full sun make sure your luffas don’t ever completely dry out either.
Pollinating your Luffa
if you have gotten this far, there is a good chance that you will see ants on your luffa. There are a lot of unconfirmed reports that ants are luffa pollinators. However, there are no scientific studies that confirm this that I’m aware of. Generally ants are considered nectar robbers and not pollinators.
If you want you can help the pollination process along. just follow the steps using this guide to understanding male and female flowers and transferring pollen with a paintbrush.
You will probably notice male flowers for weeks before the first shy female flower even appears. Then it seems, there are NO male flowers to be found! But if you’re patient, they will eventually flower at the same time. Make sure to check your flowers every day in the early morning, and be ready with your paintbrush! You still have like, 3 or 4 months to go before maturity, so the sooner the baby is pollinated, the more likely you’ll have luffas!!
Something for your Luffa to Climb on
In my experience, it isn’t the vine itself which is very heavy. But the luffas can be heavy, especially if you have a crop of more than, say 5. If you are picking the luffas early to eat, you probably won’t have any issues. But if you keep them on the vine to grow the sponge, they will get heavier and heavier. They are, surprisingly, super soaked with moisture.
Use a metal trellis which is secured on two ends. you can use an arch or a flat panel. Just make sure when using a flat panel that the top end is also supported.
Harvesting Your Luffa
If you want to eat your luffa, great. Pick them when they are only about 6-8 inches long. This is before the sponge develops. The luffa will look a lot like a zucchini.
If you want the sponges, you’ll need to wait. You may also want to pinch off new growth after the first few luffas start growing. Then, hopefully, by about September or October, you will have big luffas. If you are really lucky, those luffas will even be dry, yellowish, and light. Brown is even better. This means they have dried out and lost all of that fluid which made them so heavy. If they are not yellow, but still green, that’s OK.
You’ll need to get the luffa off the vine before any frost arrives, which is why we care about the heavy and light luffa. If you can keep the luffa on the vine until they dry that’s fabulous. But, while the best time to pick luffa is when they are yellow and dry, you CAN STILL pick your luffa when they are green. As long as it has been on the vine for a month or two, you can be reasonably sure that the sponge has developed on the inside.
Since this post is already WAY too long, I am going to save the information on how to peel your luffa for later on in the summer. You need time to grow your luffas now, anyway! 🙂 And we can also talk about how to save luffa seeds!
Happy growing. XO
