10 Plants we rely on

The banana is a very important staple food crop in the tropics.

There are about 1,000 types of banana: sweet, savoury, round, bent, straight, green, yellow, pink, silvery, even spotted and striped. Hundreds of different banana and plantain cultivars are grown for domestic consumption, but ‘Cavendish’ bananas dominate the world export trade and are the dessert banana we buy in UK supermarkets.

The banana plant is actually a giant herb that grows up to 7 metres tall with enormously wide leaves.

Each plant just produces one stem of bananas, holding up to 200 bananas.

It is used by half the world’s people in thousands of products from huge skyscraper scaffolding to tiny gramophone needles and from slide rules to skins of aeroplanes. It can be used to start a cooking fire in a wet rainforest and its ashes can be used to polish jewels and manufacture electric batteries. It has made bicycles, windmills, musical instruments, paperand walls strong enough to resist flood and tide.

Bamboo is one of the most versatile plants on earth, useful for its lightweight strength, which comes from its hollow stems, for its ease of working and for its simple beauty.

It is a primitive grass and was here millions of years before we walked the Earth and might outlive us all. Bamboo can survive conditions from extreme drought to 6m of rainfall.

There are over a thousand species of bamboo, growing in a variety of forms from tiny dwarfs to towering tropical giants. The tropical giant bamboo (Dendrocalamus asper) is the fastest growing plant on the planet, recorded growing 1.2m skywards in 24 hours. 

Cacao is the source of chocolate. Once the flowers have been pollinated, cacao trees produce large pods containing cacao (or ‘cocoa’) beans. When crushed the beans yield cocoa mass, the basis of chocolate.

Today chocolate is the 'sweet snack of the people' but many years ago, as a part of their rituals, Mayan and Aztec nobles drank their cocoa beans ground and brewed with chillies. This is where the Latin name Theobroma cacao, meaning 'food of the gods', comes from.

When chocolate first arrived in Spain in the 16th century some didn’t like it but sugar was added and it grew in popularity. It became a European luxury, with chocolate houses frequented by the elite springing up in the capital cities. Chocolate went on to be used as emergency rations for armies, navies and rescue teams, and eventually became a ‘luxury’ that everyone could enjoy.

The flowers are pollinated by Forcipomyia biting midges.

Today coffee is a leading commodity in world trade. At the other end of the chain, it’s a different story. Beans are still usually picked by hand, labour is high and income low.The small round fruits contain the beans. They ripen at different times, making coffee production labour-intensive. Using machines increases productivity but reduces the quality of the coffee.

The drink produced from coffee has been a driving force in history. Starting life in Ethiopia, coffee travelled to the Yemen, took a pilgrimage to Mecca and gave birth to the coffee house in the Middle East. Exchanging news and views, wheeling and dealing, chin-wagging, and even plotting – these cafés provided the place, and the coffee the stimulation.

By the 1600s coffee and its houses reached Britain and continued to spawn intellect and commerce. Lloyds of London, the Tatler and the Royal Society all started life in coffee houses. Coffee fuelled the industrial age, and is still enjoyed by millions around the world.

Often under 10% of the retail price of this valuable product is earned by the exporting countries. Responsibly sourced coffee is on the increase: what you buy can make a difference to the people who produce the stuff!

Cotton is the world’s biggest non-food crop and makes half of the world’s textiles, explosives, oil, cattle food, toothpaste. It has survived competition from synthetics but at the expense of heavy fertiliser and pesticide use and its shocking history of labour exploitation. 

This elegant, cool popular material has cost more in human misery than its competitors wool, linen and nylon. The cotton trade was a driving force in the Industrial Revolution and helped to finance the British Empire. It was the mainstay of the slave trade and contributed to the American civil war. Today it is the heavy pesticide use necessary to grow this ‘white gold’ that claims lives.

The oil palm is second only to the soybean in terms of world use as a vegetable oil. Many foods, including ice cream, chocolate and crisps, have palm oil as an ingredient. Although 90% of the world’s palm oil is used in food, other uses include soaps, shampoo, lipstick and engine oil.

Oil palms are the most important oil-producing plants of the tropics; fast growing, they yield a crop within five years. Africa uses what it grows, while the vast plantations in South-East Asia supply the world. As our demand increases, so does the march into virgin land. Palm oil production is threatening rainforests as more and more land is being cleared for plantations.

The oil palm exhibit in the Eden Project's Rainforest Biome explores the effects the production of palm oil has on the world and how we can work towards producing it more sustainably. 

Olives picked straight off the tree taste disgusting, so they are soaked in oil, water, brine or even a strong alkaline solution to remove bitter chemicals. The oil from the fruit has a long history of use in lamps and anointing the brave; now it is used mostly in the kitchen and is thought to reduce cholesterol levels and deter heart disease. 

Cultivated around the Mediterranean for 5,500 years, olive trees can survive in arid conditions for an incredibly long time (some examples are 2,000 years old). Around 10 million tonnes of fruit is processed for oil each year. The oil is also still used for massage and in cosmetics and soaps.

Ancient olive trees have considerable nutritional reserves in their woody parts, and these are mobilised when their fruit is formed, increasing the aromatic properties of the fruit and oil.

Rice is the world’s number-one food crop, feeding around half the global population. Archaeological finds suggest it was cultivated in South Korea and China 11,000 years ago.

It is a thirsty crop: on average 3,000 litres of water are needed to produce 1kg of rice. Rice fields are flooded when seeds reach seedling stage.

Rice yields were boosted in the 1960s during the Green Revolution when rapid technological advance in the production of staple foods prevented famine and disaster at a time of huge population growth. There was, for instance, a threefold increase in rice production in India.

Sugar cane sticks were first chewed for their sugary sap in New Guinea 10,000 years ago. Today we consume around 3kg a week each! Nutritionally we don’t need sugar, and its role in rotting teeth and increasing obesity – particularly as a hidden ingredient in processed food – has become a significant global health issue.

Sugar cane was possibly the first industrial crop and has a long association with slave labour. It was taken to the New World by Columbus as a potential cash crop and by 1600 sugar production in the subtropical and tropical Americas had become the world’s largest and most lucrative industry. Harsh conditions and the influx of diseases soon decimated the local Caribbean population, so African slaves were brought in. The Caribbean was the centre of world sugar production from the 1650s until the 1850s.

Originally taken as a medicine and a ceremonial drink, tea went on to play a significant role in world trade, linking east and west. After water, tea is now the most popular drink in the world, and the British are among the world’s biggest consumers of tea.

The Chinese have grown tea for over 2,000 years, first using it to treat abscesses and tumours, chest inflammations and bladder ailments. They also noticed it quenched the thirst and kept them awake. As well as being a stimulant, tea is a diuretic, meaning it makes you need to wee!