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The Flame Grapefruit Tree

The Flame Grapefruit tree is one of the best-known and most popular variations of red grapefruit. It is grown extensively throughout Florida, one of the leading producers of grapefruit in the United States. Along with its parent cultivar Ruby Red, Flame grapefruit remains one of the top choices for red grapefruit both in Florida and throughout the country.

History of the Flame Grapefruit Tree

Cluster of pinkish yellow grapefruits on a tree -- very similar in appearance to the fruit of the Flame Grapefruit tree.

The Flame Grapefruit tree is relatively new as far as fruit varieties go. It was developed through a Ruby Red grapefruit line in the late 1980s. Ruby Red itself had been developed in the 1930s and 50 years later was the most popular grapefruit cultivar produced in the United States. In 1987, researchers produced the Flame through a lab process called nucellar embryony. The result was a fruit that was similar in taste and appearance to the Ruby Red, with a few marked differences. 

Tree / Fruit Characteristics

The Flame Grapefruit tree reaches roughly 12 feet tall at full maturity with a canopy spread of eight to 10 feet. It is somewhat more cold hardy than many other grapefruit trees and may also produce more heavily. 

Like its parent the Ruby Red, the Flame Grapefruit has red flesh. However, it is actually even darker and more vibrant in color, with its pulp authentically red rather than pink. The fruit itself is medium large and has a slight blush on the outside. It is very high in juice and tends to have few if any seeds. 

Planting Zones

While it is more tolerant to cold than some other grapefruit varieties, the Flame grapefruit still needs a warm environment to thrive. It does well in USDA growing zones 8B through 10B but is cold hardy to between 15 to 20 degrees Fahrenheit. 

Size and Spacing

The Flame grapefruit is a moderately tall fruit tree, reaching roughly 12 feet tall with a spread of 10 feet. To make sure that your Flame Grapefruit tree has enough space to spread its roots and canopy, plant it at least 12 feet away from any other trees, plants, or structures. Twelve to 15 feet is ideal. 


Like most other grapefruit varieties, the Flame grapefruit is self-fertile. It will still produce fruit without a pollination partner. However, you may find that planting another red grapefruit variety nearby, including Ruby Red or Star Ruby, may encourage cross-pollination and lead to larger, healthier fruit crops.

Tree Care 

View of pinkish yellow grapefruits hanging on a tree.

Like most other grapefruit varieties, the Flame grapefruit is a low-maintenance fruit tree that is almost guaranteed to thrive with basic care.


Flame grapefruit trees prefer partial to full sunlight, which translates to six to eight hours of sunlight every day. Consider this when planting your grapefruit tree to make sure it is far enough away from other objects that might cast shade.


Young grapefruit trees need more watering, between one and three times a week. You might need to water even more during very hot, dry spells. Make sure the soil is consistently wet to about an inch below the surface. Once the tree matures, you can water about once a week.


Grapefruit trees only need basic pruning. Do this in the spring, after the fruit is harvested. Focus on dead or broken branches to promote healthy growth to fruiting limbs. 


Closeup of grapefruit infected with citrus greening, a destructive grapefruit tree disease.
Citrus greening is an especially destructive citrus tree disease to be aware of.

Grapefruit trees are prone to developing a few diseases, including bacterial blast, root rot, and others. Most concerning is the disease called citrus greening, which can destroy your tree altogether. To learn more about common grapefruit tree diseases, check out our post here


Like any other fruit tree, grapefruit trees can sustain some serious damage from pests! These include thrips, scale insects, citrus leaf miners, and others. You can control most citrus pests by hanging traps and applying insecticide. You can find out more about grapefruit tree pests at this link.

Common Uses For The Flame Grapefruit

The Flame grapefruit is a popular alternative to other more common red grapefruit varieties. It is highly versatile thanks to its complex taste and high juice content. 

What Does The Flame Grapefruit Taste Like? 

Closeup of platter of juicy red grapefruit sections -- very similar in appearance to the fruit of the Flame Grapefruit tree.

Like many other red grapefruit cultivars, the Flame grapefruit is sweet and mildly tangy. It is very juicy, making it ideal for juicing and eating raw. It has a strong classic grapefruit flavor, which might be too strong for some people. But grapefruit lovers will enjoy its intensity.


Grapefruit is often cooked in sweet dishes and desserts, but you will also find it used extensively in savory recipes. It is ideal for cooking down into relish, sauces, and other condiments. You will also find grapefruit used in baking, sometimes as an alternative to other citrus fruits in dishes like grapefruit meringue pie or grapefruit flan. 

Eating Raw

Flame grapefruits are delicious eaten raw. Their strong flavor and juicy flesh makes them a delight for grapefruit lovers. While some people enjoy putting a dusting of sugar or honey on top, others are happy to eat Flame grapefruits exactly as they are. 

Canning / Freezing / Drying

Flame grapefruits are a wonderful choice for canning and preserving, thanks to their high sugar and water content. You will find recipes for grapefruit preserves, sauces, jams, jellies, and other types of preserves throughout the internet. If you are a home canning enthusiast, grapefruit is a must on your list of things to try!

Grapefruits of all types freeze well. In the proper conditions, you can freeze grapefruit for up to 12 months. For the best results, peel the grapefruit and remove any remaining pith. Cut the fruit or separate it into its natural segments. This will make it easier to thaw and prepare when you are ready to use it. 

You can also dry grapefruit slices, though usually not for eating. Instead, dried grapefruit is sometimes incorporated into potpourri and other scented items. Flame grapefruit may be difficult to dry due to its high juice content! 

Another popular way of preserving grapefruit is candied grapefruit peel. This simple candy is made by boiling the grapefruit peel to soften it and expel the bitter oils, then sweetening it with sugar syrup. 


There are many delicious ways to use Flame grapefruits, including some dishes that you may not have heard of before! To learn some interesting ideas, check out our post on grapefruit recipes. Learn how to make delicious grapefruit yogurt cake, grapefruit and ginger pudding, and much more!

Health Benefits Of The Flame Grapefruit

Cut grapefruit half and wedges next to whole grapefruits.

Like other grapefruit varieties, the Flame grapefruit is extraordinarily healthy. It is high in vitamin C and other important vitamins and minerals, including fiber, potassium, and pectin. It has been widely studied for its effects on weight loss, with researchers concluding that, while grapefruit does not itself stimulate fat burn, it does help people feel fuller for longer.

Most interestingly, perhaps, is that red grapefruits like the Flame variety have been found to be even healthier than white grapefruits. This is due to the higher levels of lycopene, a phytochemical that has disease-fighting properties. 

Where To Buy Flame Grapefruits 

Flame grapefruit is a common variety, so you should be able to find it at your local supermarket. If you prefer to buy from a local producer, you can check farmers’ markets or other vendors. However, bear in mind that they are only grown in warm regions, so you might not be able to find them from local farmers unless you live in a very warm, humid place. 


Q: When Are Flame Grapefruits In Season? 

A: Grapefruits are winter crops, and the Flame grapefruit is no different. You will find it ready to harvest at any time between November and May, depending on where you live. 

Q: How Fast Do Flame Grapefruit Trees Grow?

A: Grapefruit trees are moderately fast growers. You can expect a young tree to grow about 12 inches a year until it reaches its full height. When a sapling is first planted, it might grow twice that much in a single summer!

Though grapefruit trees can produce fruit in their first or second year, it is best to prune this to encourage better growth and nutrient spread. It will start producing quality fruit (under the right conditions) in its third year.


Group of picked whole grapefruits on wooden surface with cut pieces of grapefruit in the foreground.

The Flame grapefruit has made a name for itself in the roughly 35 years since it got its start. Its vibrant color and high juice content make it a delicious fruit, perfect for juicing, eating raw, or adding to recipes. Have you grown a Flame grapefruit tree? Tell us about it in the comments!

Want to learn more about grapefruits? Next, visit our grapefruit trees page to discover information on planting, growing, caring, cooking, and more!