Known as 'citrus caviar', this lime variety is coveted by culinary masters. The Australian finger lime is the most challenging citrus variety to grow and the fruit can fetch prices of over $100/lb!
Australian Finger Lime Fruit
Features of the Australian finger lime:
- Colorful, with small pulp and caviar-like vesicles.
- May extract the pulp by squeezing one end of the fruit after the other end is cut off.
- Lime often used as a colorful garnish for fine cuisine, cocktails, salads or seafood.
- A firm fruit that's 3-8 cm in length.
- Thin-skinned, with shorter shelf life than other citrus varieties (~3 weeks).
- Easily sunburned.
- Harvesting while wet will rupture the fruit vesicles and cause bruising.
Australian Finger Lime Tree
Features of the Australian finger lime tree:
- Native to Australia.
- 'Brush' like lime tree that's very thorny.
- Slower-growing than other citrus varieties.
Where Will Australian Finger Lime Grow?
With proper care, Australian Finger Limes will produce decades of delicious fruit. However, the growing regions in the United States where citrus can be planted into the ground are limited to areas in California, Arizona, South Texas, Louisiana and Florida.
If you do not live in those regions, we do not recommend planting your Australian finger lime in the ground. However, we consider this a good thing, because it's going to make your citrus growing a lot easier.
Growing Australian Finger Lime Outside of Growing Zones
So how do you grow Australian finger lime outside of these growing zones? You do so by planting your tree in a container. You can use a plastic barrel, a wooden planter, a nice decorative pot, or really any sort of container that has adequate holes on the bottom for drainage.
Another option, which we enjoy, are fabric smart pots. While they do not have holes, the entire container is made of a fabric mesh which allows proper drainage and aeration of the soil.
The Planting Process for Growing Australian Finger Lime Trees in Pots
The actual planting process of growing Australian finger lime trees in pots is very straightforward, with standardized use of potting soil and watering and fertilizing schedules.
You can keep any citrus tree pruned back, but the Australian Finger Lime is naturally a smaller dwarf type variety which gets to be about 4 to 6 feet, while still producing an abundant harvest.
Step 1: Container for Australian Finger Lime trees
The keys to an appropriate container are having sufficient drainage through the material either being some sort of mesh cloth or have a few holes on the bottom of your planter.
Secondly, the size of the pot should be at least 1-gallon, with our favorite size recommend being 5 gallons. We find that anything above 25 gallons is quite difficult to physically move by only one person.
Step 2: Soil for Australian Finger Lime trees
Choosing soil for your Australian Finger Lime trees is simple. You can use any sort of potting mix. We do not recommend gardening soil or topsoil to use for container gardening. This is advantageous because even if you lived in a citrus growing region, you would have to take into consideration the type of soil.
With a standard potting soil for your container gardening, you do not need to worry about any of these factors. You also don't have to worry about the pH balance of the soil. We recommend you grow these lime trees in containers and use any standard potting soil which is available at your local nursery garden center supply store.
Step 3: Watering for Australian Finger Lime trees
Watering is crucial, typically when Australian finger limes are planted into the ground there is a worry of proper drainage and overwatering your tree. Australian Finger Lime trees planted in the ground prefer to have their roots a bit on the dry side. We have found that if there is proper drainage in container gardening it is difficult to overwater citrus trees.
AFL trees are VERY tricky to grow, and they are quite sensitive to underwatering!
The best way to figure out how much water your citrus tree needs is to actually look at the tree. If the leaves are wilted and dry, your tree needs more water. After watering, the tree’s leaves should perk up.
Overwatering Your Potted Citrus Tree
Overwatering is a possibility and we find that this especially happens when the trees are indoor and there's a garden saucer used underneath the pot. When there's a garden saucer there is impeded drainage, which is helpful while you're on vacation and cannot water your tree for a week, or when you have your trees indoors to prevent water seeping onto the floors and causing damage.
However, if trees are over-watered, the plant leaves will wilt and may turn a bit yellow and look sad. Watering more will only adversely affect the plant as the condition that led to the plant being yellow and sad had not been reversed.
Giving your tree a break by taking it outside if possible or letting the soil drain without a garden saucer in the bathtub for a day is a good solution. Afterward, you can adjust your watering schedule appropriately.
Step 4: Fertilizer for Australian Finger Lime trees
Your Australian Finger Lime tree will need both macro and micronutrients, just like a human. The macronutrients that all plants need are Nitrogen, Phosphorus, and Potassium. You have likely seen fertilizers and soil which state three numbers together, this is the N – P – K system which shows the concentration and relative amounts of nitrogen, phosphorus and potassium respectively.
These machinations are very important for the color of the leaves, development of the root system, proper flowering, fruiting, and taste of the fruit respectively and appropriate photosynthesis and growth of the trunk of the tree in general.
Micronutrients are also very important - think of these as vitamins for humans. They are needed much in smaller quantities and plants can have characteristic symptoms if they have a micronutrient deficiency. We will detail out micronutrients and symptoms of deficiencies in later articles.
Between regular potting soil and the fertilizer we recommend, you will have all the macronutrients and micronutrients that your tree needs and a simple fertilizing schedule for easy and effective fertilizing when you get your tree and for every February, May, and August. See our fertilizer schedule below for amounts that we recommend.
Ounces to use every Feb, May, and Aug
Nelson Plant Food - Citrus
Step 5: Sunlight for Australian Finger Lime trees
Sunlight is crucial to Australian finger lime trees, especially because it is a tropical plant. In most areas of the United States, you want to maximize sunlight with full sun exposure. If you are planting indoors, make sure that it has full sun next to the window, but we would also recommend having a grow light.
Our Grow Light Recommendation
We love SANSI 24W LED grow lights. They have a clean white light because they are full spectrum. They have all the right mix of light spectrum for growth, leaf flush, flower blossoming, and fruit set. 24 watts is a good amount of power for indoor lighting. We recommend placing the grow light anywhere from 6 to 18 inches away from your tree.
Your tree needs 12-16 hours of light a day. You can be very flexible with your light. You can keep it on for many days straight. However, all citrus trees need some dark time.
You can easily use one grow light for 1-3 trees. An easy way is to use one light on a tree for 24 hours at a time.
All grow lights get hot. We prefer SANSI because they use ceramic sinks to dissipate the heat. We have found the majority of grow lights on Amazon to have disturbing safety profiles. Use standard safety precautions, don't let babies and pets stare directly into the light or touch the heat from the grow light!
Our socket/clamp Recommendation:
Citrus does best when it has six hours of sunlight a day. If the temperature is consistently above 90° especially for younger trees, there may be some wilting of the leaves. This wilting will reverse however and at this point, it would be advantageous to keep your tree by elementary and partial shade.
Step 6: Winter Protection for Australian Finger Lime trees
We recommend that under freezing temperatures, you move your Australian Finger Lime tree into a warmer area such as a garage or indoors for the entire winter. At this point, you can utilize grow lights for continued growth.
AFL trees are VERY sensitive to cold!
There is nothing more frustrating than losing years of work and future decades of fruit than losing your citrus tree to a freak cold-snap which occurred while you were vacationing out of town! Citrus can die with exposure to temperatures in the teens for even up to 12 hours.
Important Considerations for Australian Finger Lime Trees
It is one of the most challenging and slowest growing citrus varieties there are! Even with micro-budding, this tree will take years to produce fruit!
Step 7: Where Do I Buy My Australian Finger Lime Tree?
First of all, if you live in the states of California, Arizona, Louisiana, or Florida, you will need to purchase your Australian Finger Lime tree locally as they cannot be imported into your state because of USDA regulations.
Step 8: Harvesting your Australian Finger Limes
It takes a long time to get good Australian Finger Limes. Once they are ready, they should be firm to touch and full, and when you tug at the fruit it should come away from the branch quite easily. Then you cut the pod and squeeze the magical little vesicles out and enjoy!
Growing trees is fun, but if you want to have delicious, seasonal citrus fruit right away, join the Craft Citrus Club!
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