What Is Oolong Tea?

In China, people love to say: “Drink green tea in summer, black tea in winter, and oolong tea all year round.” It's not just a catchy phrase. It is an expression of how versatile oolong tea is.

Oolong is a partially oxidized tea that fits right between black and green tea. It is one of China's six main tea types. Locals love to call it qing cha (blue-green tea).

But oolong doesn't just spell the difference between black and green tea. It has the most complex production processes you'll come across. Most especially, its roasting techniques give the tea its unique character. 

Take Wuyi Rock Tea, for example. We know global tea lovers chase it for its deep and layered flavor. And that's thanks to the skillful roasting during processing.

When it comes to the main producing regions, Fujian, Guangdong, and Taiwan take the trophy.

So, what makes oolong special, compared to other tea categories?

Three things, especially:

• It’s made with special skill. Oolong tea processing is unique and takes longer than other teas. It involves withering, bruising, oxidation, fixing, rolling, drying, and roasting.

• It has a wide oxidation range. The oxidation ranges from 10% to 80%, depending on the tea variety and the traditions of each region. 

• It has rich, layered aromas and flavors. The varying levels of oxidation give oolong teas their signature depth and complexity.

A classic hallmark of oolong tea is its floral and fruity aroma. Each cultivar puts its own spin on the fragrance. Tieguanyin, for example, will impress you with its pungent orchid aroma. Da Hong Pao, on the other hand, keeps things subtle and reserved with a fruity profile.

In the rest of this write-up, I'll walk you through the history, types, and producing regions of oolong. I also tell you about the methods and techniques of processing and brewing, and a few tasting tips. 

History of Oolong Tea

Legend says oolong tea has roots in the Northern Song Dynasty (960–1127) in Beiyuan, Fujian. This is one of the oldest imperial tea production areas in China. History suggests the techniques from that region shaped how oolong developed over time.

But the peak of oolong production, as we know it, didn’t really take off until the Qing Dynasty. Besides, there’s still some debate about the true origin of oolong tea. Some say Anxi, others the Wuyi Mountain. Regardless, most experts agree on Fujian.

Where is Oolong Tea Produced?

The heart of oolong production is in southern China. We are speaking of Fujian, Guangdong, and Taiwan. Fujian and Guangdong sit side by side on the coast. Taiwan lies just across the strait from Fujian. Together, the three form the terroir of traditional oolong tea.

Let's underline some specifics of each region and its oolong tea.

Fujian Oolong

Fujian oolongs are generally divided into two sub-regions: 

• Minnan Oolong (Southern Fujian). Famous for teas like Tieguanyin, Yongchun Fo Shou, Zhangping Shui Xian, and Baiya Qilan.

• Minbei Oolong (Northern Fujian). Produces teas such as Wuyi Rock Tea (Yancha) and others from Jianyang and Jian’ou.

Guangdong Oolong

This region is known for Phoenix Dan Cong, grown in Chaozhou. For the best quality, look for teas from the Phoenix Mountain region.

Taiwan Oolong

Tea gardens in Taiwan spread across Taipei, Nantou, Chiayi, and other counties. 

You should know that most top-quality oolong teas grow in high mountains, above 800 meters. These conditions—cooler temperatures, slower growth, and frequent mist—tend to produce leaves with greater aromatic complexity and a more refined mouthfeel.

Not Wuyi Rock tea, though. This blend has a unique character not attributed to altitude. It comes from the Danxia landform, known for the reddish sandstone of Wuyi Mountain.

Oolong Tea Cultivars

Oolong tea plants belong to the Camellia genus (Camellia sinensis). In China, some of the typical oolong tea plant varieties include:

Wuyi Caicha (武夷山菜茶)

Back in the day, locals called the Wuyi cultivars that made rock tea, caicha. But after years of careful selection and refinement, we now have Da Hong Pao, Rou Gui, and others. 

Plenty of lesser-known varieties also exist. They include Bai Ji Guan, Su Xin Lan, Tie Luo Han, and more.

Regardless of type, Wuyi rock teas undergo the same processing method. But each cultivar has its own distinctive aroma and character. This is what makes Wuyi Rock Tea unique and fascinating. 

Fact is, you may find similarities with Phoenix Dan Cong. But Wuyi cultivars are distinct in their processing styles. Also, Wuyi Rock tea is generally produced only once a year.

Tieguanyin (铁观音)

Tieguanyin is another separate cultivar, and its tea has the same name. 

You can easily spot Tieguanyin by its thick, fleshy leaves and orchid fragrance. The tea has rich internal compounds. 

Local folks sometimes call the Tieguanyin cultivar “Red-Heart, Curved-Tip” (红芯歪尾). This name describes how new buds pop out and have a reddish-purple color. The veins stand out, and the leaf tips bend a bit to the side.

Higher anthocyanin levels give the cultivar its reddish color and floral aroma.

Phoenix Dan Cong (凤凰单丛)

Phoenix Dan cultivars are another whole adventure. Their tea comes from individual plants, selected from Phoenix Shui Xian tea trees. Each tea tree exhibits a unique aroma. 

People further classify Dan Cong teas into Ten Major Aroma Types. 

There are blends named Honey Orchid, Gardenia, Yulan Magnolia, Zhilan Orchid, and Osmanthus. Others include Ginger Flower, Cinnamon, Night-Blooming Jasmine, Jasmine, and Almond.

Taiwan Oolong

Taiwan has its typical oolong cultivars, too. Common ones include Qingxin Oolong, Jin Xuan, Cui Yu, Tieguanyin, Si Ji Chun, Baiwen, and others.

Here's a table summarizing the specific cultivars in each of the four producing regions.

Oolong Region	Core Producing Areas	Tea Plant Type	Representative Cultivars / Teas
Minnan Oolong (Southern Fujian)	Anxi, Yongchun, Zhangping	Minnan oolong cultivars	Tieguanyin, Yongchun Fo Shou, Zhangping Shui Xian, Baiya Qilan
Minbei Oolong (Northern Fujian)	Wuyi Mountains, Jianyang, Jian’ou	Wuyi local cultivars (historically Caicha, later selected cultivars)	Da Hong Pao, Rou Gui, Shui Xian, Bai Ji Guan, Tie Luo Han
Guangdong Oolong	Phoenix Mountain, Chaozhou	Phoenix Dan Cong cultivars (selected from Phoenix Shui Xian tea trees)	Honey Orchid, Gardenia, Yulan Magnolia, Zhilan Orchid, Osmanthus
Taiwan Oolong	Nantou, Taipei, Chiayi, high mountain areas	Taiwan-developed oolong cultivars	Qingxin Oolong, Jin Xuan, Cui Yu, Tieguanyin, Si Ji Chun, Baiwen

 

How Oolong Tea Is Processed

Oolong tea processing has a complex sequence: 

Picking → Sun Withering → Indoor Withering → Bruising (摇青) → Oxidation → Fixing → Rolling → Drying → Roasting.

Picking

Harvesting oolong tea kicks off in the morning. But there's a caveat. 

Picking too early keeps too much moisture in the leaves, making processing difficult. And depending on the type, you must know the right maturity stage for picking.

Sun Withering

After picking, farmers spread the fresh leaves out in the sun. This dries excess moisture and softens the leaves, initiating the dehydration process.

Indoor Withering

Indoor drying follows sun withering. It serves to continue leaf drying and softening in a cooler environment. This prepares them for the next step.

Bruising (Tossing)

In this stage, the leaves are tossed in a rotating drum. This allows the leaf edges to rub on each other, and the nutrients move from the stems to the leaves. Both processes initiate oxidation.

Oxidation

For oolong tea, oxidation isn't a one-instant process. It’s a cycle of repeated indoor withering and bruising. There are two things to note about oolong oxidation: 

• Higher oxidation → more cycles of withering and bruising

• Light-aroma oolongs → fewer bruising cycles

The time you put in the oxidation process determines the final flavor, aroma, and how the tea feels in your mouth.

Fixing

Once the tea master is happy with the oxidation level, the leaves get a quick blast of high heat in a wok. This stops oxidation and locks the aroma.

Rolling

While the leaves are still warm and pliable, they’re rolled into shape. Some end up as long strips, others as semi-ball shapes.

Drying

The leaves are thoroughly dried using a drying machine to remove remaining moisture. Lightly oxidized oolongs may be packaged after this step.

Next, the leaves go into the drying machine to remove any leftover moisture. Lightly oxidized oolongs are packed right after this.

Roasting (a step specific to certain oolongs)

Some teas, such as Wuyi rock tea, Guangdong oolong, and traditional Tieguanyin, still need roasting after drying. This happens once the leaves rest a bit from the drying procedure.

Roasting pulls out any leftover moisture and stabilizes the flavors. It also brings out those deep roasted, fruity, and caramel notes that you enjoy in your tea. No wonder some teas go through multiple drying rounds before you can say they are done.

Oolong Tea Oxidation Level

The degree of oxidation in oolong tea varies widely, ranging from 10% to 80%. Different oxidation levels determine the tea’s aroma and flavor. This isn't a mere technical detail. It means everything about the tea's quality:

• Lightly oxidized oolong teas have a fresher and smoother taste. Their floral notes stand out clearly.

• As oxidation levels go up, the floral notes turn into ripe-fruit aroma. In some oolongs, you'll even think you are biting a juicy peach.

Other factors also determine the taste and aroma of oolong tea in the oxidation process.

The first is the roasting.

Lightly-oxidized oolongs, including fragrant-style Tieguanyin, Wenshan Baozhong, and Oriental Beauty, skip roasting altogether. They only get a single drying to keep their delicate, flowery character.

Traditional oolongs, like Wuyi Rock Tea and Guangdong oolongs, go the opposite direction. After initial processing, they undergo light, medium, or heavy roasting.

Roasting gives them a richer, fuller flavor. It also dries them further, increasing their shelf life in storage.

The other factor is sun withering.

Here, the tea leaves soak up the sun to lose moisture. Although it might seem like a simple process, it greatly defines the aroma. In fact, when the weather does not play along, and it's rainy, tea makers are forced to opt for indoor withering. They have to warm the leaves in drums. 

Overall, however, sun withering gives the best results, as it enhances the aroma.

Aroma and Flavor of Oolong Tea

Oolong teas have a wide flavor spectrum thanks to the oxidation level and roasting. In fact, if you ask oolong lovers what their tea smells like, you'll get a long list of aromas. Some will say crisp cucumber, floral, honey+floral, ripe fruit, and others even caramel. 

The variety of the plant also matters when it comes to the aroma. For example, Tieguanyin is famous for its orchid scent, and Rou Gui has a spicy note. Old-bush Shui Xian has a woody, almost earthy feel.

Lightly oxidized oolongs shine with freshness, sweetness, and floral notes. Roasted and more oxidized blends have a deeper, smoother, and richer flavor. The flavor lingers longer in your mouth.

Benefits of Oolong Tea

Oolong tea doesn’t just taste good. It is packed with plenty of good stuff. 

Recent clinical trials show that oolong is loaded with anti-inflammatory and antioxidant properties. Drinking oolong regularly has benefits for lower blood lipids and blood pressure. It also has the potential to reduce the risk of diabetes or heart disease. 

In addition, oolong is linked with successful weight management for reducing belly fat. Plus, it can also improve cognitive function.

For further details, we have a complete article on oolong tea benefits. 

How much Caffeine is in Oolong Tea?

If you’re watching your caffeine intake, you'll be happy to know that oolong is a perfect middle ground. It has less caffeine than coffee, just 30-70mg caffeine in a standard, 8-oz cup. The same amount of coffee has about 95mg of caffeine.

Oolong caffeine release and energy boost are also smoother. Besides, it has L-theanine, a compound that enhances alertness and relaxation.

Caffeine levels vary by cultivar, processing method, and the picking and brewing standards. Learn more about how these factors affect the caffeine content in oolong tea.

How to Store Oolong Tea

Storing oolong tea depends on a few factors, mainly oxidation level and roasting.

Higher oxidation and roasting (lower moisture)

You can store oolongs with higher oxidation and roasting levels sealed at room temperature and away from light.

That’s because they go through fuller oxidation and roasting, resulting in lower moisture content—often less than 6%.

Oolongs you can store at room temperature include Guangdong Dan Cong, Wuyi Rock Tea, traditional Tieguanyin, and Taiwanese Oriental Beauty.

These teas hold up well for years, and slow aging can bring out new and more complex flavors.

Lower oxidation with little or no roasting (higher moisture)

Lightly oxidized oolongs are a different story.

Because they undergo little or no roasting, they retain more moisture. For this reason, they should be vacuum-sealed and refrigerated. They are not meant for long-term storage.

Drink these fresher teas within a year to fully enjoy their fragrant, delicate taste.

Examples include fragrant Tieguanyin, light-roast Dong Ding Oolong, and Wenshan Baozhong.They usually undergo only a single drying step and are not fully oxidized.

How to Prepare Oolong Tea

There are two oolong tea brewing methods: The Gongfu method and the Western method.

Gongfu Brewing Method

We recommend brewing your oolong tea with the Gongfu brewing method using a Gaiwan for the best oolong tea experience. The general rule here is a 1:20 tea-to-water ratio. That means you'll use 5 grams of tea with 100ml of water.

Here's how you do it:

• First, preheat your gaiwan with hot water. It will help release the tea's aroma better.

• Add 5-6 grams of oolong tea to your gaiwan and pour about 100ml of boiling water.

• Leave the tea to steep. The time can go from 15-30 seconds, depending on whether it's the first or subsequent infusion. It also depends on the tea shape. Ball-shaped oolongs take longer than strip-shaped oolongs.

• Change the steeping time for each infusion based on the oolong type and what you like. We recommend you keep it below 30 seconds.

• Use oolong tea 6-10 times. The number of times depends on the tea quality. High-quality oolongs show more resilience.

Western Brewing Method

Western-style brewing typically uses a large mug or teapot. If you use this method:

• Add 3-5 grams of tea to 8 oz of water. 

• For the first infusion, leave the tea steep for 3 minutes.

• Use the same tea 2-3 times and adjust the steeping time to suit your taste preferences.

Note: Medium and highly oxidized oolongs are best brewed in a Gaiwan, as this method offers greater control and helps reveal their layered aromas and evolving flavors.