Solanum melongena or Japanese eggplant refers to all eggplant varieties grown in Japan, Orient Express and Millionaire being the most common.
These varieties of the nightshade family are more slender and smaller than Chinese eggplants and are slightly sweeter.
While easy to care for, part of growing Japanese eggplants is knowing the best time to harvest them.
When to harvest Japanese eggplant? As a warm-weather crop, your Japanese eggplants won’t survive the frost. Timing when you plant them plays a big role in how quickly they grow. Roughly, they will be ready for harvest 65 to 80 days after transplanting. Depending on your climate, this should be around July through September.
How Do You Know When Your Japanese Eggplant Is Ready to Harvest?
Japanese eggplants are loved for their almost seedless and firm flesh and glossy, thin exterior, which can be anything from royal purple to black-ish.
They have a mildly sweet flavor with earthy undertones, making them the ideal pairing for different spices, sauces, and aromatics.
That said, you can only enjoy all these things if you harvest them at the right time. So, how do you know when they are ready for picking?
The right size
How big and long the fruits are will depend largely on the variety of Japanese eggplant you are growing.
For instance, the majority of the varieties grown in home gardens produce fruits that are anywhere from five to eight inches long.
If you want to grow and harvest eggplants smaller than those, try the Japanese White Egg variety.
On the other end of the spectrum is the Japanese Pickling, which can grow to become lengthy fruits measuring 22 to 26 inches. Yep, that’s longer than two feet!
Plump and glossy purple exterior
There is an easy way to tell when eggplants are ripe, and you probably already know about this or do it yourself.
Basically, all you have to do is try to poke the skin with your finger. If doing so does not leave a permanent dent on the exterior, the fruit is most likely ripe enough for picking.
On the other hand, if your fingernail punctures the skin, there’s a good chance that your Japanese eggplants are too far gone.
In addition to being plump and firm, you can also check the skin for wrinkles; a ripe Japanese eggplant is glossy and is the right beautiful purple color.
That said, don’t expect it to have a near-black color, like Italian eggplants.
One way to know for sure if the fruits are already ripe for picking is to take one and slice it open.
With a ripe Japanese eggplant, you will notice that the skin is delicate and tender, while the flesh is tightly packed, pale, and with small seeds.
Where you live and the climate in your area
You can also base your harvest times on where you are located and the climate in your area.
Generally, Japanese eggplants can be made available year-round. However, in most cases, the peak harvest times will be between summer and fall.
In fact, this crop can only thrive and produce a bigger yield when grown in areas where daytime temperatures are upwards of 75 degrees Fahrenheit.
What Happens if You Don’t Harvest Japanese Eggplant?
Know anyone who doesn’t get annoyed biting into a bitter eggplant? We know we don’t like it, which is why we pay attention to harvest times.
Sadly, not everyone does.
When left on the plant to mature, the fruit will develop darker seeds, with the flesh around them becoming looser and looser.
What’s more, since the plant’s goal is to produce fruits with seeds, not harvesting ripe fruits sends a signal to the plant that its work is done.
Therefore, it will dial down on producing eggplant fruits, which means a smaller yield for you.
Not harvesting at the right time will also negatively affect the eggplants’ texture and flavor quality.
As such, we advise frequent and regular harvesting to encourage the plant to produce more fruits.
Depending on how quickly they grow in your area, you can harvest Japanese eggplants once or twice a week during harvest season.
How To Harvest Japanese Eggplant?
If you’ve tried growing eggplants before, there’s not much of a difference in harvesting Japanese eggplants.
Even so, we’ll list down the steps below to give you a refresher on the basics of harvesting eggplants:
Step 1: Prepare your tools.
When harvesting Japanese eggplants, it’s a good idea to use a sharp and clean knife or garden shears.
Disinfect the blades using rubbing alcohol to prevent contaminating the plant’s stems and causing diseases.
You will also want to prepare the basket in which you will put your freshly harvested Japanese eggplants.
Step 2: Locate which eggplants are ripe enough for picking.
Following the tips we shared, identify the mature enough eggplants from the ones that still need some more time growing.
Look for fruits that are roughly five to eight inches long, have a glossy finish, and have a firm and plump texture.
You don’t have to harvest them all in one batch, as you’ll notice that some grow quicker than others.
Step 3: Cut the fruits from the vine.
Hold the fruit with your non-dominant hand and cut the stem from the vine with your other hand.
Make sure you don’t damage the stem so as not to stress the plant. This way, it will not be discouraged to grow more fruits.
You will want to harvest Japanese eggplants every other day to promote a bigger yield.
Step 4: Check the health of your plants.
When doing this, it’s also a good idea to remove weeds that compete with your plants for space, water, and nutrients.
Also, check for bug and insect infestations, diseases, and other problems.
Watch out for sunscald, which is when the fruits turn white or develop a pale brown patch because of too much direct sun exposure.
You can remedy this by giving your plants some shade.
Step 5: Store your fresh harvest properly.
Freshly harvested Japanese eggplants will last for a week when kept in a cool place away from direct sunlight, like a root cellar.
In humid conditions no lower than 50 degrees Fahrenheit or 10 degrees Celsius, they will keep well for two weeks.
Some prefer putting them in the fridge, but the environment may be too cold for them and can make them deteriorate quicker.
A good trick is to keep them in a plastic bag with holes to allow air to circulate.
Should You Wash Japanese Eggplant After Harvesting?
Like most produce with thin skin, we don’t advise washing Japanese eggplants after harvesting them.
This is because exposing them to water or even just extra moisture will speed up their lifespan. The same is true when you leave them in a very hot and humid spot.
To extend their shelf life, find a cool, dry area that is not exposed to direct sunlight and has ample ventilation.
It would also help to keep them away from other products known to produce high levels of the fruit-ripening hormone, ethylene, such as tomatoes and bananas.
Cutting and peeling Japanese eggplants in advance before you’re ready to use them is also not a good idea.
That’s because exposing the insides to air or oxygen activates the enzyme known as polyphenol oxidase, leading to browning.
This is the same oxidation that happens when you cut potatoes and apples.
Can You Eat Japanese Eggplant Immediately After Harvesting?
Yes, absolutely! Japanese eggplants are harvested only when they are ready to eat and won’t last long in storage.
Again, this is because they have thin skin that can’t protect them from the extra moisture in the air.
After harvesting, simply rinse them thoroughly under running water, and they should be good for cooking.
If you harvested them before they are ripe for eating, you could try ripening them by leaving them on the kitchen counter at room temperature.
Others put them in a paper bag not only to speed up the process but also to ripen them evenly.
In the instance that you got too many to consume within a week, you can also freeze eggplants for later use.
However, to do so, you will need to wash, slice, fry, or bake them first before packing them in layers in a freezer bag.
Make sure you put wax paper in between the layers to separate them.
For whole eggplants, you may blanch and grill or roast them in the oven before freezing.
That said, keep in mind that frozen eggplants won’t taste as sweet and earthy as freshly picked ones.
Japanese eggplant has a firm texture that becomes creamy when cooked. Even so, it can hold its shape, unlike bigger varieties.
It also doesn’t need salting before cooking because it has firmer flesh.
For these reasons, you will often find it used for stir-frying, grilling, broiling, and baking.
Its mildly sweet flavor profile makes it perfect for pairing with sesame, mint, garlic, basic, chiles, and other herbs and spices.
As a member of the nightshade family, this purple-colored fruit is high in anthocyanins, which is a known antioxidant.
It is also a good source of dietary fiber, potassium, and B vitamins.