The fruit from the Eureka lemon tree (Citrus x limon 'Eureka') is sold commercially around the globe. Although this tree is native to California, its origins go back to 19th century Italy.
Growing your own Eureka lemon tree isn't too tricky if you live in a hot Mediterranean-type region where it can get plenty of sun in well-drained soil. Even if temperatures dip in winter, because these trees do well in a dwarf form in containers, they can easily be moved indoors for overwintering.
As well as producing an abundant crop of fruit throughout the year, Eureka lemon trees make an attractive garden addition. The foliage turns from a bronze shade to a bright green when established, and their white blooms are fragrant, pretty, and have a purple-tinged bud.
Alongside the Lisbon variety, the Eureka is a popular lemon sold in grocery stores. Although similar in look and taste, they do have several distinct differences.
Eurekas don't have such a prominent mammilla (protruding nipple), and their skin is more textured. It's still possible to confuse the two varieties when studying the fruit alone. However, the trees and their growth habits make identification easier.
Eureka lemon trees don't have the thorns you find on the Lisbon type, but, they aren't quite as cold tolerant, and need to be moved indoors if there's even the slightest sign of frost.
Eurekas have a more spreading growth habit and open form, while Lisbon lemon trees are more upright and their fruit grows inside the dense canopy of the tree as opposed to the outside.
The juicy, tangy, sour pulp of the Eureka lemon is perfect for culinary purposes and is also used for cleaning around the home.
|Botanical Name||Citrus x limon 'Eureka'|
|Common Name||Eureka lemon tree, lemon 'Garey's Eureka'|
|Plant Type||Evergreen tree|
|Mature Size||Up to 20 ft. tall|
|Sun Exposure||Full sun, partial shade|
|Soil Type||Loamy, sandy, Cclay|
|Soil pH||Well-drained, moist|
|Hardiness Zones||9 - 11, USDA|
|Toxicity||Toxic to cats|
How to Plant Eureka Lemon Trees
Lemon trees are particularly sensitive to cold weather conditions. The trees really need a warm and sheltered position to thrive.
Because they like a lot of water, it isn't recommended to plant your Eureka lemon tree directly into a flat lawn, especially if there are drainage issues. Not only will the surrounding grass not appreciate so much water, but the tree could get oversaturated.
Building up a wide mound to plant the tree on top of, or selecting a sloped position will mean it can still receive enough water without you having to worry so much about drainage.
Eureka Lemon Tree Care
If you live in a region where frost arrives in the winter, you should grow your Eureka lemon tree in a suitably sized container that can be overwintered indoors.
Access to plenty of sunlight is a must for Eureka lemon trees. Ideally, at least ten hours a day. Although they can cope in a partial shade location, they won't produce an abundant harvest, and their growth rate will slow significantly.
You'll need well-drained soil for your Eureka lemon tree. Preferably it'll be loamy or sandy, and they thrive in acidic conditions.
Eureka lemon trees are more water-hungry than the Lisbon variety. Ensuring the soil is kept consistently moist is recommended. In the summer, you may need to water the tree every day.
Don't be tempted to mulch around the tree as this can result in waterlogging. Although these trees like to be kept moist, they can't stand saturated conditions or standing water.
Temperature and Humidity
Well-suited to Mediterranean-style climates, Eureka lemon trees aren't a cold-tolerant species. If temperatures reach as low as 20 degrees Fahrenheit, your tree will likely not survive outside. They also don't cope well with harsh winds and need a sheltered location.
When the temperatures drop, container-grown trees should be moved indoors to a warm and sunny spot until the return of warmer temperatures.
If your house is very hot and suffers from dry air, using a humidifier can help to ensure the tree receives enough moisture and remains healthy and fruiting.
Their preference is to be kept in temperatures of around 45 degrees Fahrenheit or above for year-round fruiting, although increased cold hardiness does develop as they mature.
Heavily fruiting trees like the Eureka use up a lot of energy and are always hungry as a result. They appreciate organic matter being added to their soil and having a bi-annual feed with fertilizer that is specifically designed for citrus trees.
Are Eureka Lemon Trees Toxic?
While, of course, the fruit of this tree is edible for humans, it is problematic for cats and dogs. The compounds contained in the fruit, skin, and plant materials can lead to gastrointestinal upsets and skin irritations.
Harvesting Eureka Lemons
It can take at least three years before your tree is fully established and ready to produce a healthy crop. If you do spot any random flowering in advance of this, it can be a good idea to remove them to allow all the energy to be conserved to support appropriate early growth.
This type of lemon tree is known for producing a good crop throughout the year when the conditions are right.
As with all citrus fruit varieties, the Eureka lemon won't ripen off the tree. It should remain there until soft to the touch and fully ripened and ready to use.
Because of their open-spreading habit, Eureka lemon trees won't need pruning regularly the way the upright Lisbon variety will. It'll just be a case of trimming away diseased, damaged, or overcrowded sections. This can be done at any time of the year on an evergreen tree like this.
Over the years, Eureka lemon trees can reach up to 20 feet in height. If you want to keep them more compact, this will be when pruning may be more of a necessity.
Propagating Eureka Lemon Trees
Unlike some other citrus varieties, lemon trees are pretty easy to propagate from semi-hardwood cuttings. Be sure to select healthy, new growth during the late spring or early summer and cut a section that doesn't have any flowers or fruit on it.
Make sure the cuttings are kept in a moist but well-drained medium in warm conditions while waiting for them to root.
This type of lemon tree is generally best overwintered indoors unless you have particularly mild winters. They are not known for their frost tolerance and they don't take well to the soggy conditions that can be created by mulching.
Make sure you position them in a warm, bright spot if you want to continue to be able to produce a good fruit harvest. Be careful temperatures are not overly hot, though, as those that mimic those of early spring can encourage a more abundant bloom.