Thai Arabica vs. Robusta: What’s the Difference?

You’ve probably noticed that some of the coffee sold in Thailand (including Red Cliff) is advertised as 100 percent arabica coffee. But do you know the difference between Thai arabica and other varieties of coffee? If you’re a coffee drinker in Thailand, there’s a good chance that you’ve tasted at least two different species. In this post, we’re going to take a look at what those coffee species are and how they differ.

Only Three Species of Coffee Are Commercially Grown

There are at least 100 species of coffee tree that naturally occur in the wild. However, most aren’t cultivated because they don’t produce coffee worth drinking. When it comes to drinkable coffee, there are three main species: 

• Arabica (Coffea arabica)
• Robusta (Coffea canephora)
• Liberica (Coffea liberica) 

For the purposes of this post, we’re going to touch on liberica coffee briefly and then leave it out of the discussion after this paragraph. It originated in Liberia and had a good run in the late 1800s when coffee farmers planted liberica to replace their sick and dying arabica plants during a major blight. It’s still grown in parts of Java and the Philippines today – but coffee drinkers continue to show a strong preference for arabica. 

Before we go any further, we should also note that some coffee species can be crossed. There was actually a natural hybrid of arabica and robusta discovered on the island of Timor. There are always potential advantages to hybrids, and botanists are constantly looking for new ways to improve cultivated plants by crossing them with other species. Even so, most of the cultivation going on today involves variations of single coffee species.

Robusta Coffee Trees in Thailand 

Robusta accounts for approximately 30 percent of the world’s coffee cultivation, but it’s the main coffee crop grown in Thailand. Arabica is growing in popularity, but robusta dominates. It’s primarily grown in Southern Thailand in these six provinces: 

• Chumphon
• Nakhon Si Thammarat
• Krabi
• Ranong
• Surat Thani
• Phang Nga 

The word ‘robust’ applies in every sense for this variety of coffee. Robusta trees are big, strong and hearty. They produce more coffee beans than arabica trees – and the beans they produce have around double the caffeine content. It even packs in more antioxidants than arabica. 

The tradeoff is in the favor profile. The coffee brewed from robusta beans has low acidity and a high degree of bitterness. It packs a powerful punch but isn’t nearly as palatable as arabica, with one exception: robusta is perfect for Thai-style iced coffee. 

That strong flavor profile still shines through even when you pour in a lot of sweetened condensed milk and sugar. That’s why robusta coffee is such an important crop for Thailand. Think about all of the café boran carts you’ll find in virtually every city and town across the country. All of these vendors are using robusta, both because it’s cheaper and because it makes a better cup of Thai iced coffee. 

But that’s only the beginning. When you empty a packet of ‘3 In1’ into a cup of hot water, you’re brewing up a cup of robusta. Granted, it has also been pre-brewed and then freeze-dried or spray dried – which is why you don’t have to deal with any spent coffee grounds. But that’s essentially what robusta tastes like. 

A now-dated report published at Chiang Mai University in 2002 says Thailand produces around 80,000 tonnes of robusta each year. But even a quick survey of the shelves of your local 7-Eleven tells you that growing and processing robusta is big business in Thailand. Instant coffee is everywhere, and lots of people drink it.

Thai Arabica Coffee Trees

Arabica is the fairer species of coffee grown in Thailand. The trees are smaller and a bit more delicate. They need to be planted at higher elevations and perform best with at least partial shade. They’re also more prone to pests and disease – especially a type of blight known as ‘leaf rust’. 

Arabica coffee is aromatic and has a much milder flavor than robusta. Depending on soil conditions and the way it’s processed, arabica can produce a much subtler and more nuanced cup of coffee. It’s the coffee of connoisseurs. To put this in perspective, arabica coffee dominates international cupping contests. Some countries are even creating separate robusta competitions, just so that first place doesn’t always go to arabica. 

If Arabica coffee didn’t taste so good, nobody would bother planting it in Thailand. After all, Arabica trees don’t even produce as much coffee as Robusta trees do. But the mild and aromatic coffee that you can brew from Arabica coffee beans is worth all of the extra care and attention that these trees require.
The excellent flavor of arabica coffee comes with a price. Arabica trees are sensitive. They require excellent soil, high elevation and shade in order to thrive. And as we mentioned above, they also get sick more easily than robusta trees. Farmers who grow robusta trees have to constantly be on guard against pests and leaf rust. 

Arabica was originally planted in Northern Thailand through the Royal Project Foundation. It was introduced as an alternative to opium, which was widely grown throughout the Golden Triangle. When Red Cliff formed in 2008, a few farmers had already planted arabica in the Akha village where we operate. Those early adopters are now doing exceptionally well, and many more farmers have planted arabica in the years since. It’s safe to say that Thai arabica coffee has established itself as a lucrative, legal and reliable cash crop for Akha hill tribe farmers. 

There’s More Than One Type of Thai Arabica Coffee 

Arabica is a species of coffee, but it also comes in several different varieties (which are called ‘cultivars’). These are the result of selecting breeding to produce coffees with a specific traits and flavors. Some cultivars offer more nuanced flavor profiles. Others produce stronger plants that are more resistant to disease. Still others produce higher yields – which farmers understandably appreciate. 

The primary cultivar of arabica grown in Thailand is called ‘catimor’. There are a few different sub-varieties of this plant, and we know of at least two that are being grown in the area around Red Cliff. Coffee farmers love catimor, because it doesn’t succumb to leaf rust easily. It also produces a lot of coffee beans per tree. In fact, you have to be careful with catimor. If you don’t prune catimor trees, they may end up producing more coffee than they can handle. 

This hard-working coffee tree is perfectly suited for the highlands of Chiang Rai. But we had a suspicion that other varieties of arabica may also thrive in this environment. When we first started Red Cliff Coffee several years ago, we brought a few specialty varieties of coffee with us and planted them at Pha Deng Luang in Chiang Rai’s Wawi sub-district. We planned on experimenting with these arabica cultivars to see if any did well in the local soil and climate. 

One of those varieties is our rare specialty coffee that we brought back from Hawaii. It’s doing exceptionally well in the Chiang Rai mountains, and we’re convinced that future Thai coffee farms are also to feature this cultivar. With that in mind, we’re going to keep cultivating, selecting and reseeding this specific type of arabica with the hope of contributing to a more diverse selection of Thai coffees.

If you have any specific questions about the type of Arabica that we offer, please don’t hesitate to get in touch with us. We love talking about coffee in Thailand, and we’re eager to connect with other people who feel the same way.