Why do my oranges taste like lemons? | How to make them sweet

Oranges can taste sour like lemons if they are grow in a lot of shade, if the weather has been very cold, if the orange tree is getting too much water or not enough nutrients. The other main reasons why oranges can taste like lemons is if you have a sour orange tree. These are an old variety or they can grow from the rootstock of grafted orange trees.

Why oranges taste like lemons

Here are the top reasons why oranges could taste like lemons.

Here are the top reasons why oranges taste like lemons.

1. Too much shade

Oranges love sun to ripen, develop their sugars and taste sweeter. Oranges grown in deep shade will take a long time to ripen and even when they turn orange they can still taste sour.

My orange tree is grown in part shade and takes a long time for the oranges to turn sweet. Once an orange is picked it really won’t get any sweeter off the tree so leave it on until it ripens.

2. Cold weather

Warm weather at the end of the orange ripening season will help them to sweeten up while very cold weather can slow the trees growth and cause oranges to taste like lemons. Oranges will form over the cooler months but can stay sour if the weather stays too cold throughout the year.

3. The orange is too old

Oranges that are left on the tree for too long can start to develop a sour taste. While this is similar to a fermented sourness, an old orange left on the tree or on the ground can taste sour like a lemon.

Orange trees that have been picked and left on the shelf inside can also sour as they. Start to break down. Keep oranges in the fridge to keep them sweet for as long as possible and pick them at peak ripeness for the best taste.

4. Too much water

Too much water given to the orange tree can cause the oranges to taste like lemons. As nutrients are washed down the tree can struggle to get all that it needs and the oranges that grow can end up tasting sour.

5. Not enough nutrients

Orange trees that do not get the range of nutrients they need can struggle to grow well and may produce oranges that are sour like lemons. Feeding the orange tree well is essential for sweet oranges was the nutrients are needed by the tree to form and develop the orange fruit.

6. Harvest time is not right

Some oranges including Valencia can take many months to ripen, even when they look orange they may not be ripe yet. This will mean that the orange can taste sour and even have a light yellow skin like a lemon.

Allowing oranges to ripen on the tree is essential to allow them to develop their sugars and to taste delicious.

Wait until oranges feel heavy before picking one and tasting it.

7. Some varieties are sour

Orange trees that produce fruit that taste like lemons could be an old variety of sour orange. Old style oranges were sour, smaller and were often used in marmalades or in cooking.

If you have moved into a new home, you will never know what orange tree you have inherited. Some orange trees will just taste sour. Those grown from seed rather than grafted can end up tasting sour as there is no control over the pollination and therefore the resulting fruit.

If you have a sour orange, a new orange tree stem can actually be grafted to one of the branches of your main tree. A professional can do this or you can give it a go yourself.

Sour oranges: Old variety which can take over

The bottom half of a grafted tree can be a sour orange variety that may take over the sweeter grafted top. Sour orange varieties are often used as root stock because they are hardy but the oranges they produce are very sour.

You will see the stems growing from below the graft line, which is where the stem usually bulges where they were joined.

How to make sour oranges sweeter

Orange trees that are producing fruit that taste like lemons can be helped along to taste sweeter. Here are my top ways to make sour oranges sweeter.

Plant them in a sunny position

Oranges that are grown in full sun will produce sweeter fruit. When planting out a new tree, choose the sunniest position possible to allow the fruit to get bright light and develop sugars to taste sweeter.

For established orange trees, remove any overhanging branches from nearby trees or bushes and thin the bush slightly to allow more light in to reach the fruit.

Good quality soil

Good quality soil and a range of nutrients is essential to help the orange tree to develop sweet fruit. Start by preparing a new hole with compost, aged cow manure and pelleted chicken manure. Add worm castings if you have them and mix it all through.

Established orange trees can be top dressed with a mix of compost and aged cow manure in spring. Just rake the mulch back and lay the compost and cow manure mix on top of the soil. The old mulch can be raked back over and the whole mix can be watered in.

Add pelleted chicken manure to the orange tree during the warmer growing season to give it the range of nutrients it needs to grow great tasting oranges.

For more on this, check out how to top dress orange trees.

Leave the fruit on the tree until it is ripe

Allowing the orange fruit to ripen on the tree is essential to getting sweet, delicious fruit. Oranges that are picked too early will not develop the sugars off the bush in the same way as out in the sunlight.

Test the fruit before picking to see if it feels heavy. Test an orange by tasting it before harvesting the whole crop. That way you can tell if the fruit has developed to its desired sweetness and are ready to pick.

For more on this, check out my previous article on how to pick oranges.

Water it well

Regular water will help orange trees to develop, juicy, delicious fruit. While too much water can wash away nutrients or cause root rot, the perfect amount helps the tree to form plump, sweet oranges.

Oranges like regular water so water deeply over the warmer months. I like to water my orange trees deeply every 3 days over summer and top up with water every week over winter.

I live in a high rainfall area, but if you have dry summers make sure oranges are watered deeply around their whole root zone. Water in the morning and keep the water at the root base rather than on the leaves.


Mulching orange trees will help you to grow more oranges and sweeter fruit. Mulch helps to keep the water in the soil for longer and will reduce the loss of the precious water you add through evaporation.

Mulching will also help to reduce competition from weeds which can take up nutrients and water from the plant.

Following these steps gives you the best chance of sweet oranges and not fruit that taste like lemons.

Why do my oranges taste like lemons? | Summary

Oranges will taste like lemons if they are lacking the nutrition, sunlight or water they need. Sour orange varieties will have a strong sour taste that really can’t be improved so choose a variety that is grafted onto good root stock like Navel or Valencia.

Allow oranges to ripen on the tree and they will sweeten up and taste delicious.

Happy growing.