Bush lemon is a large shrub or small tree with evergreen foliage, and it’s also known as rough lemon. This naturalized plant grows in many parts of the world, but especially in Australia, where it is used to make lemon butter.
It isn’t a true lemon, but a citrus hybrid. Rough lemon fruit is a cross between a mandarin orange and a lemon.
In Australia, this small tree grows on roadsides and on farmland. But, in other countries, it is not so widespread.
This perennial shrub is hardy and produces fruits that are lemon-shaped and knobbly. They have such thick skin that their use as a fruit is limited. In the past, this plant was used to graft lemon rootstock but was not always a successful selection.
Rough lemons originated in India, and were exported to Africa and then to Europe and America around a thousand years ago.
|Scientific name||Can be year-round|
|Common names||Rough lemon, bush lemon|
|USDA Plant Hardiness Zone||Zones 9 to 11|
|Native to||India, but naturalized around the world|
|Blooming season||Can be year round|
|Plant specific features||Produces lemon fruits, very thick-skinned and knobbly|
How to Plant and Grow Lemon Bushes
Like most species in the citrus genus, Citrus jambhiri is self-fertilizing and therefore can be planted singly. It is an eye-catching addition to your garden, especially when in full blossom or when its evergreen foliage is laden with unusual fruit.
Where to Plant
If you have a sunny patio, then this is an ideal place in which to place a container growing rough lemon. If the shrub is container grown, it can be moved to a protected position to overwinter.
In a warm climate, planting a rough lemon makes a good choice for a hedge. Citrus limon jambhiri is evergreen and has attractive dense, dark green, foliage, so provides privacy.
The branches are covered in very sharp thorns which is good for security, and its fragrance and fruits are an additional bonus.
This species of citrus will not tolerate salty conditions, so should be avoided if you live in a coastal location, unless you are growing as an indoor plant.
When to Plant
A container-grown plant can be planted year-round.
Lemon Shrub Care and Maintenance
Citrus limon jambhiri grows best if planted in moist soil that drains well. It will survive in clay or sandy loam but prefers a pH level between 6 and 8.
Once the rough lemon is established, it is a drought-resistant shrub. After a long period of dry weather, it will recover quickly.
When it is in its flowering stage, however, do water your lemon tree. If it doesn’t get enough water at this time, the flowers can fail to set fruit and fall off the plant. Although it will recover, you will lose precious lemons!
You should feed this plant regularly, with a fertilizer designed for citrus. It needs feeding regularly, and providing it has sufficient nutrients, will flower and fruit year long.
Plant the bush lemon shrub in full sun if possible. This will encourage flowering and fruit production.
Pruning and Repotting
The bush lemon tree can be pruned to around 2m. This makes it effectively a dwarf tree, so it is useful if space is limited.
One of the advantages of bush lemon over other citrus species is that it has the longest propagation season.
This is a shrub that will propagate from seed, albeit very slowly. The seed germination will occur fairly quickly in warm conditions, but the plant will not flower or fruit for several years. Rough lemons grown from seeds will produce plants that are the same as the parent plant.
More commonly, propagation of Citrus limon jambhiri is carried out by taking softwood cuttings, or by grafting or budding. These methods should be started in the spring when the plant is beginning to produce new growth.
Stem cuttings should be taken when the stem is still soft and hasn’t yet become woody.
Cuttings should be around 6 inches (15.24 cm) long and all lower leaves, apart from the top two, should be cut off.
This will aid the plant to conserve moisture whilst it is developing its own root structure. If you use hormone rooting powder, this will help the cutting to the root.
Pests and diseases
The most common problem with this plant is ants, which are often the result of an aphid infestation. Other pests will cause leaves to drop, and the debris and rotting vegetation will attract the ants.
Temperature and Humidity
Citrus limon jambhiri has some frost tolerance. It will grow in a temperate, subtropical, or tropical region. It can also be planted as an indoor plant, placed outside in warm weather.
Increased soil temperatures will result in faster top and root growth of the rough lemon.
Rough lemon is a fairly vigorous plant which is why it is used as a rootstock for other citrus hybrids. Nevertheless, although it will not suffer as much as other varieties, the shrub will still become stressed if its roots are subjected to flooding conditions.
When planted in conditions that are too wet, the shrub produces fewer fruit as it becomes older. Planted in better draining, drier soil results in bush lemon trees remaining healthy, and productive for considerably longer.
Other Uses for Rough Lemon
Rough lemon fruit is used in many recipes, including drinks, butter, and desserts.
Bees and other beneficial insects will be attracted to the fragrant lemon blossom.
The fruit is not marketed commercially, due to its low juice content, and very thick skin but is very popular for home use due to its sweeter and stronger lemon flavor.
Types of Rough Lemon You Can Grow
There are cultivated varieties of bush lemon, and the Ponderosa lemon resembles bush lemon due to its thick and rigid skin.
Bush or rough lemon is itself a hybrid variety and a cross between a citron (lemon) and a mandarin orange. Another hybrid between the mandarin orange and the citron is the rangpur. This is very acidic in taste and has orange skin and pulp.
A number of hybrids of bush lemon are used as citrus rootstock. There are advantages in using bush lemon for this purpose, such as the bush lemon’s drought resistance.
Conversely, there is a tendency for citrus trees grafted onto bush lemon to bear sour, thick-skinned fruit.
Citrus that are grafted onto bush lemon rootstock may develop suckers at the base of the plant. It’s essential to remove these suckers promptly, otherwise, they will take over the grafted citrus, depriving it of nutrients and moisture.
The plant will revert to the bush lemon (rootstock) and you will lose the hybrid lemon tree.
If you have the chance to grow a rough lemon tree, make sure you reserve some harvested fruit to make some lemonade. You will be smitten by the superior quality of both the aroma and the taste! Reserve the rind to use in your cakes and desserts.
*image by valtercirillo/pixabay