Date trees reach up to 30 metres (100 ft) in height, growing singly or forming a clump with several stems from a single root system. Slow-growing, they can reach over 100 years of age when maintained properly. Date fruits (dates) are oval-cylindrical, 3 to 7 centimetres (1 to 3 in) long, and about 2.5 centimetres (1 in) in diameter, with colour ranging from dark brown to bright red or yellow, depending on variety. Containing 61–68 percent sugar by mass when dried, dates are very sweet and are enjoyed as desserts on their own or within confections.
Read Pritish Kumar Halder full blog, to know some interesting facts about the date palm, a flowering plant species in the palm family.
Dates have been cultivated in the Middle East and the Indus Valley for thousands of years. There is archaeological evidence of date cultivation in Arabia from the 6th millennium BCE. The total annual world production of dates amounts to 8.5 million metric tons, countries of the Middle East and North Africa being the largest producers and consumers.
Date trees reach up to 30 metres (100 ft) in height, growing singly or forming a clump with several stems from a single root system. Slow-growing, they can reach over 100 years of age when maintained properly. The roots have pneumatodes. The leaves are 4–6 metres (13–20 ft) long, with spines on the petiole, and pinnate, with about 150 leaflets. The leaflets are 30 cm (12 in) long and 2 cm (1 in) wide. The full span of the crown ranges from 6–10 m (20–33 ft).
The date palm is dioecious, having separate male and female plants. They can be easily grown from seed, but only 50% of seedlings will be female and hence fruit bearing, and dates from seedling plants are often smaller and of poorer quality. Most commercial plantations thus use cuttings of heavily cropping cultivars. Plants grown from cuttings will fruit 2–3 years earlier than seedling plants.
In 2009, a team of researchers at the Weill Cornell Medical College in Qatar published a draft version of the date palm genome (Khalas variety). The draft genome sequence was improved in 2019 with the release of a more complete genome sequence using small molecule real-time sequencing technology by a team from the New York University Abu Dhabi Center for Genomics.
Dates are a traditional crop throughout the Middle East and north Africa. Dates (especially Medjool and Deglet Nour) are also cultivated in the southwestern United States, and in Sonora and Baja California in Mexico.
Date palms can take 4 to 8 years after planting before they will bear fruit, and start producing viable yields for commercial harvest between 7 and 10 years. Mature date palms can produce 70–140 kg (150–300 lb) of dates per harvest season. They do not all ripen at the same time so several harvests are required. To obtain fruit of marketable quality, the bunches of dates must be thinned and bagged or covered before ripening so that the remaining fruits grow larger and are protected from weather and animals, such as birds, that also like to eat them.
Date palms require well-drained deep sandy loam soils with a pH of 8–11 (alkaline). The soil should have the ability to hold moisture and also be free of calcium carbonate.
In 2020, world production of dates was 9 million tonnes, led by Egypt, Saudi Arabia, Iran, and Algeria with 60% of the world total combined (table).
A large number of date cultivars and varieties emerged through history of its cultivation, but the exact number is difficult to assess. Hussain and El-Zeid (1975) have reported 400 varieties, while Nixon (1954) named around 250. Most of those are limited to a particular region, and only a few dozen have attained broader commercial importance. The most renowned cultivars worldwide include Deglet Noor, originally of Algeria; Yahidi and Hallawi of Iraq; Medjool of Morocco; Mazafati of Iran.
Diseases and pests
A major palm pest, the red palm beetle (Rhynchophorus ferrugineus), currently poses a significant threat to date production in parts of the Middle East as well as to iconic landscape specimens throughout the Mediterranean world. Pinhas et al. 2008 uses piezoelectric sensors and speech recognition technology to detect R. ferrugineus. They achieved a 98% detection ratio on young P. dactylifera in very controlled laboratory conditions. Another significant insect pest is Ommatissus lybicus, sometimes called the “dubas bug”, whose sap sucking results in sooty mould formation.
Dry or soft dates are eaten out-of-hand, or may be pitted and stuffed with fillings such as almonds, walnuts, pecans, candied orange and lemon peel, tahini, marzipan or cream cheese. Pitted dates are also referred to as stoned dates. Partially dried pitted dates may be glazed with glucose syrup for use as a snack food. Dates can also be chopped and used in a range of sweet and savory dishes, from tajines (tagines) in Morocco to puddings, ka’ak (types of Arab cookies) and other dessert items.
Date seeds are soaked and ground up for animal feed. Their oil is suitable for use in cosmetics and dermatological applications. The oil contains lauric acid (36%) and oleic acid (41%). Date palm seeds contain 0.56–5.4% lauric acid. They can also be processed chemically as a source of oxalic acid. Date seeds are also ground and used in the manner of coffee beans, or as an additive to coffee. Experimental studies have shown that feeding mice with the aqueous extract of date pits exhibit anti-genotoxic effects and reduce DNA damage induced by N-nitroso-N-methylurea.
Stripped fruit clusters are used as brooms. Recently, the floral stalks have been found to be of ornamental value in households.
Sweet sap tapped from date palm in West Bengal, India
Apart from P. dactylifera, wild date palms such as Phoenix sylvestris and Phoenix reclinata, depending on the region, can be also tapped for sap.
Date palm leaves are used for Palm Sunday in the Christian religion. In North Africa, they are commonly used for making huts. Mature leaves are also made into mats, screens, baskets, and fans. Processed leaves can be used for insulating board. Dried leaf petioles are a source of cellulose pulp, used for walking sticks, brooms, fishing floats, and fuel. Leaf sheaths are prized for their scent, and fibre from them is also used for rope, coarse cloth, and large hats. The leaves are used as a lulav in the Jewish holiday of Sukkot. They are also commonly used as the s’chach in the construction of a sukkah.