Star fruit tree: cultivation of distinctive tropical fruits

What is star fruit? You are in the right place. The star fruit is rich in vitamins C, B9, B6, B2 and fiber. It also contains various minerals like potassium, zinc, phosphorus, and iron. It's a low-calorie fruit with just 31 calories per 100 grams. And the star fruit tree is beautiful too!

A fully grown tree can produce up to 200 to 400 pounds of fruit each year. The star fruit is fleshy with a grape-like texture. The taste is described as similar to feijoa, but with hints of banana and pear and the acidity of pineapple.

It is also a widely used ornamental plant. With beautiful foliage and beautiful lilac blossoms, this tree can enhance the aesthetics of your garden. The flowers also attract bees so more pollinators can be attracted to your garden.

Get a star fruit tree

Good Products in Caring for a Star Fruit Tree:

Brief instructions for care

The star fruit tree produces delicious tropical fruits. Source: joe_tourist

Common Name (s) Star fruit, carambola, five fingers, bilimbi
Scientific name Averrhoa carambola
Days to harvest 60 to 75 days after the fruit has set
light Full sun
Water: Regular watering, 2-3 times a week when it is not raining
ground Well draining, many soil types
fertilizer Depends on the age of the tree
Pests Scale insects, weevils, stink bugs, pumpkin bugs, thrips
Diseases Fungal leaf spot, algae rust, anthracnose fruit rot, pythium root rot

Everything about star fruit

Carambola branchesCarambola branches produce leaves that face each other in the branch. Source: Rigid

The star fruit plant has the botanical name Averrhoa carambola. However, the tree and fruit have many common names in different regions. In Spain and the surrounding area, for example, the tree is known under the name Carambola. In Indonesia it is called bilimbi, although this name also refers to Averrhoa bilimbi and therefore is not often used for star fruit.

The averrhoa carambola tree is generally multi-branched and has dark green, bushy foliage. It can grow up to 20 to 30 feet tall and 20 to 25 feet wide, but is often kept a smaller size to make harvesting easier.

It produces small, bell-shaped flowers with five petals. Their color is purple, but they have purple stripes along the petals. When grown in tropical conditions such as the southern parts of Florida, the plant typically blooms in April and May but can produce a second bloom from September to October. A few isolated flowers can appear all year round.

The star fruit season is long, with harvestable fruit appearing from June to the following February. The fruit is roughly oval and has deep depressions on its sides. When it is cut into cross sections, the depressions form a star, hence the name star fruit. It's usually light to dark yellow with slightly darker skin.

There are many types of carambola, but they fall into one of two categories: sweet or sour. The tart varieties are generally used as a side dish or in savory applications such as curries or stews. The sweet ones are used for jams and jellies, juicing, cocktails or desserts.

Like other exotic fruits, it may not be for everyone. The star fruit contains enough oxalic acid that it may be risky for people with kidney disease to consume it.

Star fruit comes from tropical Southeast Asia, where it has been grown for centuries. It was introduced by Austronesian-speaking traders in the subcontinent and Sri Lanka. Today it is grown and enjoyed almost all over the world, with Australia, Malaysia, the Philippines, Taiwan, and the United States being the top producers. India is the largest producer in Southeast Asia.

Planting star fruit trees

Star fruit budThe bud of the star fruit flower is tiny, delicate and beautiful. Source: Hey Tiffany

Planting a star fruit tree in your yard can be a lot of fun. Plus, the delicious fruit is well worth it if you are in the right area to grow it! Here are some tips on how to plant these properly.

When to plant

As a tropics, the star fruit tree should be planted in places where frost is not likely. Even so, it is still advisable to plant this tree in early spring to ensure it has time to settle in before the hot months.

When starting a carambola seed, they will need warm soil to germinate. Make sure you use a seedling heating mat with a temperature of at least 70 degrees to ensure good germination. You will likely need to grow young tree containers for a while before transplanting into the ground, possibly up to 2-3 years.

Where to plant

Full sun is necessary for star fruit to grow well. Make sure your star fruit tree receives at least 8 hours of sunlight each day and is sheltered from the wind. These plants are not tolerant of strong winds, cold climates, or in alkaline soils.

Your tree should be 20 to 30 feet away from other trees or structures. This will reduce the likelihood of the tree getting too much shade. Likewise, trees that grow in containers must be far from other trees and structures to allow good growth.

How to Plant

Once your plant is roughly 2 to 4 feet tall and at least 3 gallons in size, it's time to plant it in the ground. Make sure it is not tied to the root and that it is in good health.

Prepare your soil ahead of time by loosening it in the place where the roots will grow. Do not apply fertilizer, compost, or other additives to the soil. Instead, make sure that any large stones have these removed and that the soil is well drained and slightly acidic. Plant at the same depth that the tree was planted in its pot, but no deeper.

Carambola care

Star fruit tree in full bloomBeautiful flowers adorn the carom tree when it blooms. Source: guzhengman

Once made, the carambola is relatively easy to care for, provided you give it proper care. Let's go through the conditions your tree would want to produce incredible star fruit!

Sun and temperature

Carambola plants prefer full sun conditions. The plant prefers a hot and humid environment and is prone to frost damage. Temperatures below 35 degrees are becoming more dangerous and temperatures below 25 degrees can kill trees.

If grown outdoors, it will do best in USDA Zones 9 through 11. The temperature must be at least 60 ° F for good tree health and preferably 70-95 ° F for fruit production.

Irrigation and humidity

Your carambola is not a drought-tolerant species and needs to be watered regularly. Always keep the soil moist, but not oversaturated. Aim for 1-2 deep waterings a week when it hasn't rained. Reduce watering during the winter months if it is not necessary. A watering hose around the tree can be used to water slowly and deeply. However, base your placement on a ring roughly in the middle of the tree canopy.

Depending on its current state of health, your tree can tolerate flooded conditions for between 2 and 10 days, but suffers from a lack of oxygen at the roots. It is better to avoid flooding for this species, but if it cannot be avoided, it will not be damaged immediately.

Humid environments are ideal for this species. However, watch out for symptoms of plant diseases that are common in humid locations.

Once your tree is 1-2 years old, even watering from flowering to fruiting is important. Make sure it has the water it needs to produce lots of fruit


Carambola work well with a wide variety of ground textures. As long as the soil drains off excess moisture, it should be fine to plant your tree.

Somewhat acidic, to grow star fruit you need an acidic to neutral pH range. At more alkaline pH levels, they are prone to nutritional deficiencies. Aim for a range between 4.5 and 7 for the best growth.


Star fruit growingAs the star fruit grows, its color blends in with the leaves. Source: beautifulcataya

Carambola trees are moderately tall forage. Older trees should be fertilized 4-6 times a year and young trees every 30-60 days during the growing season. Whenever possible, aim for a fertilizer range of 6-2-6 or 6-4-6, preferably one that contains micronutrients like manganese, iron, zinc, and magnesium.

If your tree is in alkaline soil, it can suffer from nutritional deficiencies. They should receive foliar sprays containing manganese, iron and zinc 4-6 times a year.


For the first 1-2 years after planting, tips that cut branches more than 3 feet in length encourage lateral growth. This should be done in winter while the tree is resting. Older trees can be pruned to keep them 6 to 12 feet tall for easy harvest.

It is also good to examine the tree closely each year to make sure there are no inwardly growing branches. By selectively pruning the crotch of the branch to remove a few inward-growing branches, airflow and light are improved for the rest of the canopy.


Propagation of these trees is typically one of two methods: from seeds or from grafts. Other methods are rarely effective.

Grafting a carambola branch onto another rootstock is a common technique for creating nursery stock. However, it's not an easy process and is probably best left to the professionals.

Harvesting and storing

Harvested carambolaMost star fruits are eaten fresh. Source: Arbyreed

The only thing better than growing the carambola plant is enjoying the harvest! This is how you harvest and store the delicious, aromatic fruits.


Star fruits no longer ripen after harvest. When the grooves on the sides of the fruit are completely yellow and only the top tips of the raised sections are still green, it's time to start harvesting. You can wait for the top tips to turn yellow too, but in this case the shelf life won't be that long.


Your harvested star fruits can be stored in a sealed plastic bag in the refrigerator for up to 21 days. Most star fruits are eaten fresh and no longer stored.

For longer storage, puree the star fruit and freeze in an ice cube tray. You can also dry star fruits with a dehydrator. The puree can also be used to make jams or jellies. Remove the seeds while processing them for storage.


Unripe star fruitAs star fruits ripen, they gradually turn yellow. Source: Dinesh Valke

Let's discuss issues you may face with your home grown star fruit plants while you are caring for them. There aren't many of them, but they exist!

Growing problems

Soils above pH 7 can cause your home-grown carom tree to suffer Nutritional deficiency. An iron deficiency can lead to yellowed leaves with green veins or smaller leaves. A lack of manganese leads to a reduced leaf size and yellowing of the leaves. Magnesium deficiency results in mottled yellow and green leaves. Treat with the appropriate micronutrient when these occur.

In addition, old trees can handle it cold temperatures For short periods of time there are different stages of potential damage. At temperatures below 60 degrees Fahrenheit, the production of carambola fruit stops. Young leaves can die off at temperatures of 30-32 degrees. Young trees, mature leaves and young twigs can be killed at temperatures between 25 and 29 degrees. Temperatures of 24 degrees and below can kill old trees.


Three different types of Scale insects are common pests for carambola. Plumose shed (Morganella longispina) and Philaphedra scales (Philephedra tuberculosa) attack leaves and branches. Brown scales (Coccus hesperidum) attack the fruit directly. Regular spraying of horticultural oil will reduce the occurrence of these.

Two kinds of Weevils Have a look too. The Diaprepes weevils (Diaprepes abbreviatus) damages the roots and can lead to the death of the roots and shoots. A Fruit weevil Myctides imberbis can also occur intermittently and consume the delicious star fruit. Both of these are treatable with pyrethrin.

Stink bugs and Squash bugs Both can create tiny holes in the fruit that then allow fungal or bacterial pathogens to enter and cause the fruit to rot. Insecticidal soap works against stink bugs. For squash bugs, pyrethrin is a better choice and is also effective against stink bugs.

At least one type of thrips, red striped thripsalso attack the flowers and fruits. Treat these pests with insecticidal soap, neem oil, or horticultural oil.


A selection of Fungal leaf spot diseases are common on star fruit. Cercospora averrhoa, Corynespora cassiicola, Gloesporium sp., Phomopsis sp. And Phyllosticta sp. are all fungal pathogens that cause this. While this is usually not very dangerous to your tree, they do warn you that your tree is under stress. These can be nutrient deficiencies or climate-related stress. No control is required, only to identify and alleviate the cause of the stress.

Algae rust is caused by cephaleuros virescens. This form of rust causes rough gray or red circular patches on the bark and can cause the branches to die off. If you believe your tree may have seaweed rust, contact your local farming extension to confirm treatment options and for information.

Anthracnose fruit rot is not uncommon, but anthracnose leaves are usually spotted first. Treating the leaves should prevent them from spreading to the fruit and prevent any risk to your tree's fruit production. Use either a biofungicide that contains Bacillus subtilis or a copper fungicide spray for treatment. Once the fruit is infected, discard the damaged fruit.

Finally, Root rot caused by pythium fungi can occur in excessively moist soil conditions. Make sure the soil around your tree drains off excess moisture. Some soil mycorrhizae show signs of protecting plants from fungal root rot. However, once the star fruit tree is already infected, it can no longer be cured. Therefore, prevention is essential.

frequently asked Questions

Star fruit ripening on treeThe star fruit ripens on the tree, not after harvest. Source: naokomc

Q: How long does it take for a star fruit tree to bear fruit?

A: Star fruit trees typically don't produce much or no fruit for the first year. After caring for it in the first year, you can count on fruit in either the 2nd or 3rd year. Native star fruit trees sheltered from high winds can often be harvested within 10 to 14 months of planting, provided they are 2 years old or older.

Q: Are star fruit seeds poisonous?

A: Yes and no. For people with kidney disease, star fruit is generally not recommended at all because it contains high amounts of oxalic acid. If you are healthy, the seeds or fruits shouldn't harm you.

The green fingers behind this article:
Lorin Nielsen
Lifelong gardener

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