Walking through the farmers market, I can’t help but ogle the tiny baskets of cucamelons on display. I know, that’s the point, a unique and truly adorable vegetable right out front that draws you into the stand. Cucamelons (also known as mouse melons and Mexican sour jerkins) are more than just a cute farmers market novelty. These tiny mouse melons are truly delicious, with a flavor like fresh cucumber mixed with a hint of lime. Since they can be popped into your mouth on a walk through the garden, growing cucamelons is a really rewarding use of garden space.
What are Cucuamelons?
At first glance, cucamelons look like miniature 1” watermelons. The name suggests that they’re a cross between a cucumber and a melon, only in miniature. While cucumbers and melons can cross-pollinate, cucmelons are a different crop altogether.
Botanically, cucamelons are neither cucumber nor a melon, and the plants will not cross-pollinate with either. They’re in the cucumber family, but they’re a different species altogether (Melothria scabra).
Cucuamelons are nothing new, they’ve been grown in Mexico and Central America since before European colonization. In their native land, they’re known as pepquinos (little cucumbers) or sandiita (little watermelons). These days, they also go by the names mouse melon, Mexican sour gherkin, Mexican miniature watermelon or Mexican sour cucumber.
How do Cucamelons Taste?
Though one of their names is “Mexican sour cucumber” I wouldn’t call them sour. Cucamelons taste like a fresh, crisp cucumber that has been kissed with a hint of lime. That mild citrus acidity helps make these miniature mouse melons extra refreshing in the summertime.
While you might imagine that these little watermelon looking fruits might have red flesh inside, they actually just cucumbers inside, with tiny seeds and cucumber like flesh.
How to Grow Cucamelons
Though they start out as slow growing, delicate seedlings, cucamelon plants will eventually grow to be huge sprawling vines. They thrive on full sun and hot soils, and in the heat of summer the vines will take over a huge vertical trellis.
Starting Cucamelon Seeds Indoors
Start cucamelon seeds indoors about 4 weeks before the last frost date. This is the same time you start cucumbers from seed, and it’s well after other crops like tomatoes and peppers. Members of the cucumber family don’t transplant well once they’re older, so while it’s important to help cucamelons get a good early start, don’t get carried away.
Cucamelon seeds should be planted about 1/4 to 1/2 inch deep and take about 7 to 14 days to germinate, depending on temperature. Ideally, they’d be germinated with warm soil, somewhere between 70 and 75 degrees F. A seedling heat mat can ensure success if your seed starting area is cool or drafty.
In the warmest areas, you can direct seed cucamelons outdoors, but soil temperatures need to be above 70 degrees before planting. Outdoor seed starting is only really viable in areas where cucamelons can be grown as perennials, zones 7 through 10.
Transplanting Cucamelon Plants
Cucamelon plants can be hardened off outdoors after the risk of last frost has passed. After a few days getting used to the sun and air outdoors, transplant the young seedlings to well-drained garden soil.
The seedlings may be small, and the vines spindly, but they’ll really take off when things heat up mid-summer. Be sure to plant the young cucamelon seedlings 12 inches apart, and give them a tall trellis to climb. The trellis ensures that the plants get good sunlight all around, helps keep soil temperatures warm and makes the cucamelons much easier to pick.
In areas with long summers, cucamelon vines can grow 10+ feet tall, so give them plenty of vertical space.
Growing Cucamelon Plants
Once the plants are in the garden, they’re pretty low maintenance. Cucamelons are classed as light to medium feeders, and they don’t require supplemental fertilizer (except in the worst soils).
Cucamelons store energy in tubers under the soil (more on that later) and those tubers require good drainage or they’ll rot in the ground. Avoid planting cucamelons in overly wet soils. Some guides even suggest adding perlite or sand to the garden soil around cucamelons, to ensure good drainage.
Generally, cucamelons don’t require much supplemental water, but they do appreciate roughly 1” of water per week during the growing season. In extremely hot dry areas, mulch them to help maintain adequate soil moisture and water as necessary.
Cucamelon Days to Maturity
Since cucamelons are open pollinated, there’s a bit of variation in days to maturity. In general, cucamelon plants are 65 to 75 days to maturity, provided they’re grown in warm soil with strong, full sun.
While cucamelons grow best in areas with hot, relatively dry summers, they’re adaptable. The plants are commonly grown as a farmer’s market crop in the northeast, which often has cool, rainy summers. Yields may be a bit lower and plants may take a bit longer to mature, but you’ll still bring in a respectable harvest.
In the coldest areas, it’s best to grow cucamelons as tender perennial tubers, by harvesting the underground tubers at the end of the growing season and replanting them in spring.
Growing Cucamelons as Perennials
Believe it or not, cucuamelon plants are actually perennials. Below the soil, each cucamelon plant produces a tuber. While the plants are slow to start from seed, cucamelon plants grown from tubers have a head start on the growing season.
The trick is, cucamelon plants cannot tolerate cold winter temperatures, and the tubers are only hardy outdoors year-round to zone 7. In zones 7 to 10, mulch the plants during winter, and they’ll go dormant and come back in the same spot the following year.
Even in colder climates, cucamelons can be grown as a perennial with a few modifications. Cut off the vining tops after the first few fall frosts, when the plants begin to die back on their own.
Carefully dig up the cucamelon tubers, taking care not to bruise or damage them. Each plant should have produced several 4 to 6 inch warty tubers. Don’t dust the dirt off because the tubers need to be stored in soil during the winter months anyway.
Place the tubers in a bucket or pot, filled with moist (but not soaking) potting soil. You can bury them in layers to save space, but make sure there is at least 2 inches of soil above and below each tuber, and ensure they don’t touch.
Store the cucamelon tubers in soil in a cool but frost-free location for the winter. A root cellar, basement or unheated garage should be just right in most locations.
In the spring, pot up the cucamelon tubers about 6 to 8 weeks before the last frost. This should be right about when you start tomato seedlings. Allow the plants to begin growing, then once the last frost has passed, harden off the seedlings outdoors before planting them in the garden.
Here’s a great article on overwintering cucamelon tubers (with pictures) if you need more information.
Growing Cucamelons in Containers
Containers are another good option for cold climates or small space gardeners. Cucamelons take well to container growing, and in cold areas, the whole container can be brought indoors after the first few frosts. The pot should be stored in a cool, unheated space until the next growing season.
Cucamelons are also a great option for patio or patio gardeners. Just be sure to give each plant about 1 foot apart in a container. That means you’ll need relatively large containers to grow multiple plants, and most small pots can only support a single plant.
Give them a good trellis and watch them grow!
Cucamelon Plant Pollination
A quick note on cucamelon pollination…
Like other members of the cucumber family, cucamelons produce separate male and female flowers. They’re insect pollinated, most commonly by bees. Cucumbers, melons, and cucamelons are all at risk as pollinator populations decline.
To ensure good pollination, plant other bee food sources in the area, and consider hand pollination if your area is particularly short on natural pollinators. Male blossoms grow on long stems, while female blossoms have a small immature fruit attached to their base. Take a small paint brush or Q tip, tip it into a male flower and then hand pollinate individual female flowers.
This can be tedious and time-consuming, especially for fruit as small as little mouse melons. It’s easier to just take steps to ensure healthy pollinator populations in your area.
Where to Buy Cucamelon Seeds
While cucumber and melon seeds are commonly available from garden centers as small seedlings, cucamelons are a bit harder to find. For the most part, if you want to grow cucamelons you’re going to have to start them from seed. Once someone in your area is growing them, you can ask them for a spare tuber, but lacking that, seeds are the way to go.
Since cucamelons are a still a relatively rare crop, you’re unlikely to find seeds even in a well-stocked garden center. There are many seed catalogs that carry the seeds, and often you can order them alongside your other garden seeds from your preferred supplier.
Cucamelon seeds are available from Seed Needs, David’s Garden Seeds and Botanical Interests. At the time of this writing, they’re well reviewed with reports of excellent germination rates.
How to Harvest & Store Cucamelons
Harvesting cucamelons is just like picking a cucumber from the vine. They pop off easily, and you can easily harvest a bucket full in a short time. Once cucamelons are harvested, they actually store pretty well. The fruits are remarkably robust for their size, and they don’t bruise easily.
Cucamelons will keep for a long time at room temperature, but eventually, they’ll dry out and begin to shrivel. At that point, they’re still tasty, but they’ve lost their crunch. Once they’re past prime and a bit soft, cucamelons are still wonderfully infused in a bit of liqueur, where they impart their distinctive cucumber/lime taste.
I love making cucamelon gin because cucumber and lime are the perfect compliments to gin already.
How to Use Cucamelons
Beyond cucamelon gin, which is delicious, there are plenty of healthy ways to use cucamelons. They hold up remarkably well to quick cooking, and they add a lovely crunch to stir-fries if added in the last minute of cooking. That said, they’re usually eaten fresh.
Since they’re a close cucumber relative, it makes sense to turn them into homemade pickles. You can use a regular dill pickle recipe for canning, or a quick refrigerator pickle recipe and substitute cucamelons in place of pickling cukes.
Beyond pickles and popping them in your mouth right in the garden, here’s a few cucamelon recipes to get you started:
- Cucamelon Salsa
- Marinated Cucamelon Salad
- Cucamelon Sunomono (Japanese noodles w/ cucamelon)
- Cucamelon Bruschetta
- Cucamelon & Radish Salad
Feeling inspired? How do you plan to use your cucamelon harvest? Leave me a note in the comments.
Very interesting! Which vendor sells the seeds? I’m a Master Gardener and have several vegetable gardens as my projects. These would be a perfect addition.
There are quite a few, fedco and baker creek have them, but so do many others.
You can purchase seeds from this company, probably others.
Cucumbers and melons cannot cross pollinate as you stated that they could near the beginning of this article
They sure can! I’ve done it (accidentally), but I assure you they can!
I’m in Las Vegas and have twice grown beautiful cucamelon plants but they aren’t producing flowers. Any ideas?
Often a lack of flowers is either too much nitrogen (which promotes foliage but not flowers), or not enough phosphorus (needed for flower development), or both. The other potential problem is the temperature. Some crops, like tomatoes, simply cannot develop flowers or set fruit when temps are too hot or too cold. Since you’re in Vegas, my guess would be that it’s too hot for the cucamelons to flower and fruit. But that’s just a guess.
Try planting them with a partial shade covering, or plant them when it’s much cooler, like around when you grow your peas.
My cucamelon plant have only female flower. A lot of them ! I don’t see any male flowers ?
I live in Massachusetts. My daughter dug up a small plant in an area she was kayaking. We called it a mystery plant for a while, not knowing what what it was. Noticing as it grew it looked like a vine I put up an old wire door from a chicken coop. It is thriving in the area of the garden where I planted it as a seedling and discovered I am the proud gardener of a Cucamelon!!!
I’m growing Cucamelons indoors. Do the female cucamelons flowers need to be pollinated to produce fruit? I know they all start with a small fruit bud with a yellow flower, but I’m concerned they won’t produce fruit if I don’t hand pollinate.
Yes, they will need to be pollinated to produce fruit.
Can you please tell me when i can tell it’s time to pick them please
I have something like this growing wild. It is a viney thing, with white blossoms. The fruit is 1 1/2” to 2”. The fruit turns bright red very quickly all over and becomes very soft at the same time. In all other respects it is exactly like your MouseMelon. Can you give me any information on the variety I have? I would especially like to know if it is edible. Thank you.
Sounds to me like you have an ivy gourd vine. In Malaysia, we call it timun tikus which translates to mouse cucumber. The fruits turn red and mushy. I have not grown this before but purchased some seeds and will give it a try together with the cucamelon seeds I also obtained from a local nursery.
Clearing some brush/weed covered land for planting and came across what appears to be cucamelons, but they are a little more round and red in color. Not sure what they are though. Any ideas?
The leaves on my cucamelon vine are going brown. I live in a temperate region but is hot in Summer. Perhaps I’m watering the vine too much.
I have planted my cucamelon seeds and they now have two sets of leaves but the bottom set seem to be dying. They are planted in good soil, not too wet. Any suggestions?
Are there any close relatives that look just like these? After being introduced to the Gerkins through a friends garden, I saw what looked just like these growing along the road on Whidbey Island in Washington state. I stopped a picked one a took a bite and it was so very bitter it tasted like poison! I spit it out and am now wondering if it was a look alike or if they get bitter if they grow too big? Any experiences like this for anyone? Thanks so much for a great article!
I honestly don’t know about wild plant look likes, but that’s certainly possible. These are sweet and not at all bitter, so you definitely had something else…
Thank you! looking forward to growing my own this year!
I bought 3 cucamelon plants labeled as regular cucumbers from our local garden center. What a happy accident! We’re in the foothills – Zone 9 even though the real heat of Summer hasn’t hit us yet the plants are doing beautifully. They are both delicious and the cutest little veggies. Thank you for the recipes and tips.
How can I tell when it’s time to harvest?
When they’ve reached full size. They should be about an inch to 1 1/2 inches long, and about an inch in diameter.
I’ve been growing mine from seeds for 2 months indoors in an aquaponics system. They are climbing like crazy, but no flowers or anything. Any ideas.
You want to first make sure that it is getting adequate light. It should be receiving a minimum of 6 hours per day. Also excessive amounts of nitrogen can keep it from flowering so you may want to check your fertilizer. You also want to make sure that it doesn’t have too much or too little water.
Can these be grown indoors with an AeroGarden?
They get really big, like 10 foot vines or more. It might be hard to trellis that much indoors.
I have one of these vines that has chosen to grow near my Yucca plant and uses it’s dead stalks as a trellis. It has been growing there for maybe 3 years and seems to be thriving. I have tried numerous times to find out what exactly it is!! I happened upon an On Line Yard Sale site only this morning showing these and then the vine with the tiny yellow flower! Imagine my surprise when I find they are edible!! When they turn black does that mean they are going to seed and are they still edible at this time or not?? They have had the fruit every year but I had not been brave enough to try them, imagine what I have missed!!! All this time I thought of it as an annoying weed vine!!! I have also come across a Black Elderberry tree in my back yard!! Took me the better part of 30 years to figure it out!!! I worked and was out of my home for 12 to 14 hours a day and didnt have much time for anything else. I am so very pleased to find out what this vine is!!! I would love any further info. You might have to share.
What a great little surprise. I definitely would not eat them if they are turning black. You should harvest them as soon as they reach full size which is about an inch to an inch and a half long.
I’m so glad to hear cucamelons turn black. I’ve got these growing wild in Athens, Georgia, and they are smaller with paler markings than some of the more watermelon-looking ones. When I looked at the leaf and yellow flowers, I thought I had identified them as cucamelons and pickled some, but then I found some that had turned black on the vine and I was afraid to eat the pickles I had made. So can you please confirm they do turn black if left on the vine?
I cannot confirm that they turn black on the vine. I have never left them on the vine that long. My response says that I would not eat them if they are turning black. I would also not eat them unless you are able to 100% identify them as cucamelons.
Has anyone ever tried to make these into a relish? Thinking about doing these in lieu of cucumbers this year, and was hoping to can some at the end of the growing season.
I don’t see any reason why you can’t use them in relish. Let us know if you decide to try it.
Really interesting reading your blog. I am planting Cucamelon seeds for the first time. Last year (during the COVID lockdown) my grandson and I planted 180 tomato seeds and were able to send £200 Sterling to Great Ormond Street Children’s Hospital by asking people for a voluntary donation in return for a tomato plant. This year we hope to increase the total raised by introducing new plants including Cucamelon, various herbs, chilli peppers and bell peppers etc, your informative blog will enable me to provide donors with an introduction to Cucamelons. Very many thanks
That’s wonderful. I love how you are using your new found knowledge to make a difference in your community.
could you please give the temperature range for Zone 7-10?
I’m not sure what you mean by the temperature range for Zone 7-10?
i read that these cucamelons (mouse melons can be quite toxic.. what gives ??
I haven’t ever heard that before. Do you have a link to an article with this information?