How Big Do Eggplants Get?


If you are planning on growing eggplants in your garden this year, you might be wondering how big the plants and fruit will get.  That way, you can plan the number of plants and the amount of space you will need for your crop of eggplants.

So, how big do eggplants grow?  Eggplants grow 16 to 48 inches (41 to 122 centimeters) tall, 14 to 36 inches (35 to 91 centimeters) wide, and produce fruit that is 2 to 10 inches (5 to 25 centimeters) long.

Of course, the quality of your fruit (if you get any at all!) depends on the care that you give your eggplant plants.  Let’s take a closer look at eggplants, including size, growing conditions, and time to maturity.

How Big Do Eggplants Get?

Most eggplant plants will reach a height of 2 to 3 feet tall.  However, some compact varieties may only reach 16 inches tall, while some taller varieties can reach heights of 4 feet.

eggplant on vine
The fruit of eggplants can be as small as 2 or 3 inches long, or as big as 10 inches long.

Eggplant plants will generally be about 2 feet in width, although they can range from 14 to 36 inches wide.

The eggplant fruit itself is usually 4 to 8 inches long.  However, some compact varieties, such as Patio Baby Eggplant from Burpee, can have fruit as small as 2 or 3 inches long.

On the other hand, some long and thin varieties of eggplants, such as Green Knight Eggplant from Burpee, can produce fruit that is up to 10 inches long.

Although eggplants may continue to grow, it is best to harvest the fruit when they are still glossy.  Once the fruit becomes dull or brown, they are too mature.  In that case, you should compost them, or give them to your chickens!

Be careful when harvesting your eggplants, since some varieties have thorns on the stems.

How Long Does it Take Eggplants to Grow?

Eggplants can take between 52 and 80 days to mature, depending on the variety.  A healthy eggplant should produce 4 to 6 fruits in a season.

For more information, check out this article on eggplants from the University of Illinois Extension.

According to the Michigan State University Extension, eggplant seeds usually germinate in 14 to 21 days.  If your climate is warm enough, you can sow eggplant seeds directly into the soil.

Remember that eggplants are warm-weather crops.  In cooler climates with shorter growing seasons, you should start eggplant seeds indoors about 8 weeks before transplanting outdoors.  This will help to avoid late spring frosts, which can kill your eggplants.

What Do Eggplants Look Like?

Eggplants are taller than they are wide.  Some long and thin eggplant fruits are shaped like cucumbers, while short and fat ones have more of a teardrop shape.

Eggplant fruit is glossy, with a deep purple, white, or green color.  There are some white eggplants with purple specks.

eggplants
Some varieties of eggplant are purple with white specks or stripes.

Eggplants are indeterminate, so the plants will continue to grow and produce until killed by frost (or some other cause).

Are Eggplants Hard to Grow?

Eggplants like full sun and warmer temperatures, so it will be difficult to grow them by direct sowing in northern climates.  Your best bet is to start them indoors before transplanting outdoors.

Eggplants like well-drained soil with a pH 5.5 to 7.5.  However, there are many other factors that affect eggplant growth, including temperature, watering, fertilizing, and spacing.  Let’s start with temperature.

Temperature for Eggplants

The minimum temperature for eggplant seed germination is 60 degrees Fahrenheit (15.6 degrees Celsius).  If the soil is any colder than this, you will see low germination rates – that is, if you can get any seeds at all to germinate!

This is nature’s way of protecting eggplant seeds from sprouting at a time when they will be unable to survive.  This is why it is suggested that you start eggplant seeds indoors to avoid cold soil temperatures in early spring.

The maximum temperature for eggplant seed germination is 95 degrees Fahrenheit (35 degrees Celsius).  If the soil is any warmer than this, germination rates will decrease.

Combined with high humidity, high temperatures can encourage the growth of mold, which is another threat to your plants.  So, don’t wait too long to plant your eggplant seeds and transplant your established plants outside!

Eggplants are sensitive to cold, and will not set fruit below 60 degrees Fahrenheit (15.6 degrees Celsius).  You should wait until nighttime temperatures are over 50 degrees Fahrenheit (10 degrees Celsius) before transplanting eggplants outside.

The University of Minnesota Extension suggests starting eggplant seeds indoors 8 weeks before the last spring frost date.

You can find the frost dates for your area on the Old Farmer’s Almanac website.

The ideal (optimal) temperature for eggplant seed germination is between 75 degrees Fahrenheit (23.9 degrees Celsius) and 85 degrees Fahrenheit (29.4 degrees Celsius).

Keep in mind that these temperatures refer to soil temperature, not air temperature.  If you want to find out the soil temperature, use a probe-type thermometer to check.

If the thermometer reads a temperature that is too low, then you have some options.  One option is to wait until the sun warms up the soil.

To speed up this process, clear away any debris, such as leaves or grass clippings, from the soil surface.  Also make sure to choose a location for planting that gets plenty of sun, so that it can warm up the soil faster.

If you are worried about a short growing season, you can also use a cloche (a plastic or glass cover) to trap some heat and warm up the air and soil near your eggplant seeds.

A cloche can be made from a plastic water bottle to retain warmth and humidity in the soil for seeds or seedlings as they grow.

A cloche can be made from a plastic water bottle, and will keep seeds or seedlings warmer than the surrounding air, especially on sunny days.

A cloche can be made from a plastic water bottle to trap heat and moisture in a small area to help seeds germinate faster.

For more information, check out the table below, and check out this article from the University of California on ideal seed germination temperatures.

Seed
Germination
Temperature
Temperature
(degrees
Fahrenheit)
Temperature
(degrees
Celsius)
Minimum 60 15.6
Ideal 75 to 85 23.9 to 29.4
Maximum 95 35

Watering for Eggplants

Eggplants can tolerate some drought when established, but you should keep the soil moist during seed germination and when they plants are young.  Uneven watering can cause blossom end rot, as can calcium deficiency.

Later on, water your eggplants deeply & infrequently to encourage stronger, more extensive root system.  For more information on watering, check out this article on eggplants from the Utah State University Extension.

garden hose
Be careful not to over water or under water your eggplants.

If you find that you have a problem with dry soil, check out my article on how to treat dry soil.

On the other hand, over watering your eggplants (or any plants for that matter) can lead to root rot and eventual death.  The best way to decide when to water is to feel the soil with your fingers.

If the soil feels dry 2 or 3 inches below the surface, then go ahead and water.  For more information, check out my article on over watering your plants.

Try to water early in the morning, rather than at night, to allow water to soak into the soil.  Avoid getting the leaves wet to prevent rot, mold, and diseases.

Fertilizing for Eggplants

After transplanting, use a balanced fertilizer (such as 10-10-10), to encourage vine and leaf growth.  The University of Maryland Extension suggests side dressing with 1 to 2 ounces of 10-10-10 fertilizer per plant after the first fruits form on the plant.

Avoid excessive nitrogen, since this can burn plants or encourage too much green growth at the expense of flowers and fruit.

For more information, check out my article on over fertilizing your plants.

Spacing for Eggplants

Sow your eggplant seeds 0.25 inches (0.6 centimeters) deep when starting them indoors.  After the seeds germinate and the first true leaves appear, thin the seeds so they are 2 to 3 inches apart.

When transplanting outside, put the eggplants 18 to 24 inches apart to prevent competition between plants.  Leave 30 to 36 inches (76 to 91 centimeters) between rows to allow space for watering, weeding, and harvesting.

Also, consider using supports for your eggplants to give them something to climb on as they grow.  For more information, check out my article on tomato cages.

Conclusion

By now, you have a much better idea of how big eggplants grow, in terms of both the fruit on the vine and the plant itself.  You also know a bit more about the care that is necessary to ensure a healthy crop of eggplants in this year’s garden.

I hope you found this article helpful – if so, please share it with someone else who can use the information.  If you have any questions or advice about eggplants, please leave a comment below.

jonathon.david.madore

Hi, I'm Jonathon. I’m the gardening guy (not guru!) who is encouraging everyone to spend more time in the garden. I try to help solve common gardening problems so that you can get the best harvest every year!

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