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desert lime seeds

Desert lime trees retain interesting desert adaptation characteristics.  They are the quickest citrus species in the world to set fruit after flowering. They protect themselves against grazing animals by sharp thorns. However, after growing above the browse height of large kangaroos the trees grow no more thorns. Propagation is from cuttings taken high in the tree that are free of thorns. Historically the fruit was eaten by aborigines and has been used by generations of outback people to make thirst-quenching infused drinks and cordial and delicious sauces, marmalades, pickles and chutneys.

The Douglas family encourages plantings of this exceptional native citrus and will readily pass on advice from their extensive experience. 

Growing Desert Limes

Desert limes are the fruit from a tree species of true citrus, native to Australia – citrus glauca.  In their natural setting desert lime trees are bountiful fruit producers in good seasons. Desert lime trees evolved and occur naturally across the challenging outback and will thrive when taken to other environments withstanding both heat and frost. The desert lime genus citrus glauca grafts readily on to commercial citrus rootstock selections and this is the preferred propagation method for home gardens and commercial production.  Grafted trees are now growing in all States including Tasmania. Fruit is small but has exceptional flavour. Desert lime fruit has outstanding health enhancing attributes with high levels of natural Vitamin C, Lutein, Folate and the antioxidant Vitamin E.

The ‘Abundance’ selection of desert lime tree made by Jock Douglas is now available to all Australian States. It is proven as a high yielding fruit producer and has an attractive rounded shape.  Abundance desert lime trees are highly suitable as productive home garden trees and as valuable commercial producers for orchard plantings.

Desert lime seeds

In the wild Desert Lime trees evolved and occur naturally across the challenging climatic zone of Australia�s inland. Trees exhibit interesting adaptation characteristics and are tolerant of heat, frost, drought and salinity. Citrus glauca is the quickest citrus species in the world to set fruit after flowering. It is the only citrus that is an xerophyte as it can drop leaves in drought and live through the green on stems. C. glauca is edible for most grazing animals and protects against this with a covering of sharp thorns when young. However, after growing above the browse height of large kangaroos the trees grow no thorns. The fruit is small with an intense, piquant flavour. Fruit set in the wild is annual and variable, depending on seasonal conditions and the age and genetic makeup of individual trees. Citrus glauca trees will shed fruit after flowering if soil moisture is lacking but will bear profusely when conditions are favourable.

The natural distribution of citrus glauca is in the semi-arid regions in eastern Australia from Rockhampton to Longreach in Queensland and south to Dubbo in central NSW and west to Quorm, in the Flinders ranges of SA (Alexander, 1983). It grows naturally in inland woodlands and brigalow scrubs in a range of soil types and can withstand extreme temperature conditions from 45� C to � 12� C.Tree sizes vary from a slender and spiny tree up to 12 m height to a small multistemmed dense tree of 2-4 m . Blue-grey coloured leaves are slender and upward facing, 5-8mm across. White flowers appear in spring.The fruit ripens in summer and is round to oblate in shape, approximately 2 cm in diameter, weighing from 1-3 g. The skin is light yellow-green on maturity. The porous skin contains large oil glands (Birmingham, 1998).

Desert limes are true citrus closely related to conventional citrus that have been collected in the wild by Aboriginal people and early settlers. �In early New South Wales, British colonists made jams, tarts and jellies from wild fruits, many of which came into season around November, making the best of fruit too low in sugar and too high in acid to be eaten raw as a table fruit.” Maiden noted that in the inland region of NSW and SE Queensland the desert kumquat process and agreeable beverage from its acid fruit and fair preserve may be made of the fruit� (Clarke, 2008). According to the Australian National University the name native cumquat appeared in 1880. Settlers often used to compare Australian native fruits to European fruits and preceded the Australian food by the term native. Various cookbooks like the Australian Enquiry Book (Lawson, 1898), the Coronation Cookery Book (1933), the Longreach Red Cross Cookbook (1946) and the Schauer Australian Cookers Book (1952) published native lime recipes. Desert limes are viewed a traditional Australian food by FSANZ and are listed for inclusion in the Codex Alimentarius.​

Description

Desert Lime trees are suitable for home gardens and the following applies:

Distinctive piquant lime flavour and refreshing taste. Read all about ‘Defining the unique flavours of Australian native foods’ on the RIRDC website.

Functionality

Research conducted by Zhao and Agboola (2007) showed desert lime has strong activity against the common food spoilage bacteria in a methanol and water extract: Acinetobacter baumannii, Bacillus subtilis, Pseudomonas aeruginosa. The activity of desert lime methanol extract against common food-borne human pathogens showed strong activity against the cholera-causing bacterium Vibrio cholerae and Clostridium perfringens, which in the past has caused food poisoning outbreaks. Other strong activity was measured against Aeromonas hydrophila, Bacillus cereus, Campylobacter jejuni, Escherichia coli 0157:H7, Shigella sonnei, Salmonella enteritidis and Yersinia enterocolitica. In this study the antioxidant activity of desert lime measured 52.4 % of inhibition of �-carotene bleaching and showed a free radical scavenging activity of 4.5 % DPPH. The total phenolic content was 67.9 mg of GAE/L using the Folin-Ciocalteu procedure. In a study by Konczak et. al. (2009) Desert limes show an outstanding amount of Vitamin C: 1% DW- 962 mg/100g DW. Vitamin E content measured 3.999 mg/100g DW) with 88.6% contributed to α �Tocopherol, a powerful lipophilic antioxidant. Lutein measured 1.50 mg/100g DW, which is more than the Australian �Hass� Avocado regarded as one of the primary sources of lutein. Desert limes are a rich source of Ca 384.2 mg/ 100 g DW, which is almost ten times the Calcium content of Blueberries. A high potassium: sodium (K:Na) ratio, which may be beneficial to reduce hypertension was also discovered. Of twelve commercially grown and tested native food plants, Desert lime showed the highest source of folate (420�g/100g DW), which is double the recommended daily intake in 100g DW and over 10 times greater than Blueberries.

Commercial production of Citrus glauca has proven adaptable for commercial production. However, because maturity to fruiting age is slow � around ten years � trees in commercial production are grafted to a citrainge rootstock. Proven high bearing wild trees are selected for grafting. Grafted trees begin bearing fruit within three years and have proved adaptable in a wide range of locations. Recommended commercial plantings are at 5 metre spaces between trees and with 5 metres row width. This gives 400 trees per hectare but it is possible to go to 4 metre x 4 metre spaces which would be 625 trees to the hectare. Agronomy is similar to other citrus. Fruit is picked by hand or with mechanical aids used for olive harvesting. Fruit should be kept cool while harvesting as it tends to heat readily. After cleaning the fruit is stored frozen and is traded as frozen fruit. Desert Limes thaw well from frozen, retaining shape, solidity and taste.