Texas Citrus Learning Center

The Story of Texas Grapefruit

Description of Citrus Fruits


Fruits that grow on evergreen trees in subtropical regions around the world.

  • Citrus fruits include grapefruit, oranges, lemons, limes, mandarins, tangerines, tangelos, pummelos, kumquats, citron and calamondin.
  • All of these fruits are popular because of their attractive peel, fruit colors, distinctive smell and pleasing taste.


A popular citrus fruit that is a cross between a sweet orange and a pummelo

  • Larger than an orange, its peel can have a variety of different peel colors including shades of white, yellow and orange with a red blush.
  • Fruit colors include white, pink and red. The pink varieties are sweeter than the white varieties. The red varieties are the sweetest of all.
  • Texas only produces red grapefruit varieties, the Ruby-Sweet and Rio Star.


Oranges are the largest citrus crop in the world and probably the most widely known citrus fruit.

  • Oranges are round and usually have an orange colored peel. Inside of this peel or rind are sections of juicy fruit.
  • They give off a distinct and pleasing aroma, which is due to the oils found in the peel.
  • Texas produces juicy, sweet oranges including Navels, Valencias, and Early and Mid-Season varieties like Marrs and Hamlins.


Identifying Parts of a Citrus Tree

Citrus trees can be divided into several parts; the roots, trunk, leaves, flowers, seeds and fruits. Let’s take a look!

Citrus Trees

Citrus growers want to make sure a tree stays strong and healthy from the very beginning of its life. So they take a bud (twig or stem from another citrus tree) and insert into a sturdy root stock. This process is called “grafting”.

Within a few weeks the bud continues to grow and can now be called a small tree.

The tree spends the first year in a nursery where it is given plenty of water and protected from insects and bad weather. The tree is then replanted in a citrus grove where it spends the next four years maturing. Then the tree is ready to produce sweet and juicy oranges and grapefruit.

Rows of citrus trees are called groves. These groves produce lots of wonderful fruit that is ready for harvesting in South Texas between October and May every year.

Did you know that the average grapefruit acre has 140 trees, and yields almost 20 tons of fruit? That means each tree produces around 285 pounds of citrus.

Roots are very important to citrus trees.

  • A tree cannot grow above ground without healthy roots below the ground.
  • Roots are covered with small hairs, which act like straws drawing water in from the soil. It is then transported through the stems to the leaves.
  • South Texas has a sandy loam soil, which contains lots of nutrients and minerals for the roots to absorb and deliver to other parts of the tree.
  • Roots also anchor, support and stabilize the tree or plant.

Trunks & Leaves

Both tree trunks and leaves allow water and nutrients to reach the blossoms and fruit.

Trunks, branches, twigs and stems contain a transport system which allows water and nutrients to move from the roots to the leaves.

Leaves are the food factories of the tree, producing all the needed food and vitamins.

  • Plants and trees produce their own food through a process called photosynthesis.
  • Plant leaves use carbon dioxide, water and sunlight to make sugars (plant food).
  • Leaves also transpire or lose water (similar to human sweat) which helps the plant maintain its temperature and encourages roots to continue absorbing water.

Citrus Blossoms

Citrus trees have fragrant white blossoms.

  • Most citrus trees bloom in the springtime, although this can vary.
  • Orange blossoms symbolize love and were popular decorations for brides in weddings in the nineteenth century.
  • Flowers are the sexual organs of the plant. Their sole purpose is to make the seeds and fruits needed to produce more plants and ensure the survival of the species.

Seeds / Fruit

How does a flower create a seed?

Basically a flower creates a seed after a two step process; pollination and fertilization. Pollination occurs when pollen (male genetic material) is released by a flower and comes in contact with a flower’s female genetic material. Once this happens, cells divide and begin to produce fruit and seeds. This process is called fertilization.

Where are the seeds located on the tree?

Seeds are encased inside the fruit, and their purpose is to grow into new plants. Fruit’s are nature’s special packages for seeds and they begin to develop after the flower is pollinated. The fruit can also be a protective coat and aids in the transportation of a seed planting. Animals transport seeds by eating fruits and then leaving seeds scattered in their droppings.

How do seeds know when to sprout?

Seeds are very smart and they wait until the right conditions are favorable before they sprout and grow into a plant (this is called germination). Most seeds require most soil, oxygen and warm temperatures. Once the outer layer of the seed has been broken, usually triggered by cold or water, the seed is ready to soak up water and send out roots. With a little help from its stored energy, the young plant should soon be above ground, exposed to sunlight and ready to begin producing its own food.


How Texas Citrus travels from the grove to your local grocery store.

After growing red grapefruit and oranges, citrus farmers face another obstacle. They have to find a way to pick, or harvest, all of the fruit. Citrus fruit must be handled carefully in order to avoid bruising. Texas Citrus is harvested between October and May of each year.

Let’s follow the fruit’s journey from the grove to the store:

  • Texas Citrus fruits are picked by hand once they reach maturity. Citrus differs from other fruit because they are not all picked at one time and stored – they have to be ready to eat first. Farmers pull fruit samples from the trees in order to check the fruit’s color and sugar level. Texas Oranges have a yellowish color when they are ready to be picked while Texas Grapefruit has an orange color that can include a pinkish blush on the peel.
  • Once citrus fruits are harvested, they are placed on trucks and sent to a packing house. At the packing house, fruits are unloaded and the leaves and other debris are taken out. Any fruit that does not pass inspection goes directly to a juice plant. From there it is squeezed by machines to release the juice.
  • When Texas Red Grapefruit and Oranges arrive at the packing shed, they are washed and waxed by a machine. Washing removes dirt and enhances the appearance. Since the natural wax is stripped off during this process, the fruit is given a layer of safe wax to help prolong the taste and life of the fruit.
  • The fruit is then graded (or sorted) by human eyes. Any fruit that is scarred or misshapen is also sent to the juice plant. Fruit that passes inspection is separated into 2 categories, Fancy (nice appearance) and Choice (still good quality but might have a little scarring on the surface).
  • Then it is sent along a special conveyor belt called an Optical Sorter. This machine takes pictures and maps out the surface of the fruit in order to distinguish its size. Once it’s sized, the machine drops the fruit into wooden bins below. There is a bin for each standard grapefruit and orange size.
  • Almost every piece of Texas Grapefruit or Orange is given a identification sticker on the peel. The sticker tells you and your local supermarket clerks the fruit’s variety and origin.
  • Texas Citrus is then packed by hand in boxes, bins, or cartons. Finally, it travels by truck to select grocery stores across the United States and Canada. Once at the store, shoppers are encouraged to look for citrus that is heavy for its size, which usually means it has allot of juice. Don’t forget to look for Texas Citrus in your local grocery store October through May.

History of Grapefruit & Oranges

What is citrus and where did it come from?

  • Citrus can be defined as a family of trees that are grown in warm regions for their edible fruit, thick rind and pulpy flesh.
  • Citrus fruit includes oranges, grapefruits, mandarins, tangerines, tangelos, lemons, limes, citron and pummelos.
  • Citrus trees, originated in southeast Asia, and have been grown and prized for thousands of years.
  • The first citron fruits to arrive in Europe appeared around 2000 B.C., when Alexander the Great conquered western Asia.
  • Europeans enjoyed eating and cooking with citrus, using it to season meat and fish.
  • Citrus, especially oranges were considered a luxury in colder climates. It was very expensive to transport the fruit, so oranges were mainly eaten by royalty, including Kings and Queens.

When did citrus finally arrive in North America?

  • It is thought that Christopher Columbus brought orange seeds to Hispaniola in 1493 on his second voyage to North America.
  • Citrus seeds were first brought to the Americas in 1518 by Spanish and Portuguese traders.

When and where was grapefruit discovered?

  • A few hundred years after citrus seeds were introduced to the Americas, a new citrus fruit, called a grapefruit, emerged.
  • Grapefruit was developed in Barbados in the 1750’s as a mutation of the sweet orange and the pummelo.
  • Originally known as the “forbidden fruit”, grapefruit got its present day name after a Jamaican farmer noted how the fruit grew clustered together on the tree – just like a bunch of grapes – thus the name “grapefruit”.

When did Texas begin growing grapefruit and oranges?

  • It is believed that the first grapefruit and orange seeds were brought to South Texas by Spanish missionaries from the West Indies.
  • The sweet red grapefruit, which has become so popular, was accidentally discovered in 1929 by Texas citrus growers. They found red grapefruit growing on pink grapefruit trees.
  • This grapefruit became known as the Ruby Red grapefruit. The Ruby Red was the first grapefruit to be granted a United States patent.
  • Over the next several decades even redder mutations of fruit were discovered by citrus growers.
  • Each new discovery was named after the grower who found it.
  • Texas produces approximately 27,000 acres of citrus every year.
  • In 1993, Texas Red Grapefruit was named the State Fruit of Texas.