The almond tree (Prunus dulcis or Amygdalus communis) is a fruit tree with deciduous leaves and is typical of temperate or warm zones due to its low tolerance to cold.
The ideal soil to plant an almond tree is a loose, sandy soil that has good drainage and does not oppress its roots. It belongs to the Rosaceae family, which is one of the most evolved and numerous in species.
It is mainly cultivated for almonds, although care must be taken to differentiate the sweet almond from the bitter one, which is toxic for pharmacological use.
The early flowering of the almond tree and the fact that the fruit is not harvested until 9 months after the beginning of this flowering is very curious . It is, therefore, a long maturation process characteristic of this tree.
There are varieties of the late-blooming almond tree that growers use for areas prone to late frosts. In addition, it is important to cultivate on slopes or sunny land that facilitates the escape from frost and allows the activity of bees to proliferate for pollination.
On the other hand, and speaking precisely of the bees in charge of pollinating the almond tree, the rains during the flowering season complicate the process quite a bit.
history of the almond tree
The almond tree began to be cultivated in Persia, Syria and Palestine. In the legends of the bible, the patriarch Abraham used almond sticks to build corrals where he closed his numerous herds and the famous staff of Aaron was a branch of the aforementioned tree. In the Bible, the almond tree symbolizes vigilance and good fruit, which is why it appears among those selected by Aaron and is present in Paradise on Earth. For this reason it often surrounds paintings of the child Jesus (the fruit of the Virgin) or his mother.
The Greeks were the diffusers of this plant species throughout the Mediterranean. At the end of the 18th century, some Franciscan missionaries, led by Friar Junípero Serra (a native of Petra), planted almond trees from our lands in the Californian region of San Diego.
The almond tree is a deciduous tree of the Rosaceae family that can reach up to 10 meters in height. Its trunk is smooth and greenish in its young stage but becomes cracked and grayish in its adult stage. It blooms between the months of January to April and bears its fruit between the months of August to October.
The leaves of the almond tree are long and narrow and have jagged edges.
Some of the most cultivated almond varieties in Spain are the Marcona, Largueta, Planeta, Mallorca or Mollares.
Root: The almond tree has an axonomorphic root with a main axis more developed than the lateral ones, in a radial system, little branched, well attached to the ground and grayish-yellow in color when young.
Trunk: The stem is woody and sympodic branching, that is, different divergent branches come out of the main trunk; it is smooth, green and brown when young and scaly and gray in the adult tree.
Leaf: Its leaves are simple, lanceolate, with an attenuated base, an acuminate apex and therefore markedly pointed, and its margins are slightly serrated; they have a leathery texture, a pinnate rib, and are deep green in color.
The almond flower can appear alone or in groups of 2 to 4. It has five petals whose color varies between pink and whitish tones.
The fruits, the almonds, are up to 6 cm long and have a drupe shape.
As you will see, the almond tree is a tree that is significantly sensitive to certain climatic conditions but very resistant to others. You simply have to choose the most suitable variety of almond tree for the climatic characteristics of your area.
Flower type and reproduction:
Almond flowers are hermaphrodite and monoecious, since they have androecium and gynoecium in the same flower and both sexes coincide in the same individual. Its inflorescence is racemose and grape-shaped, that is, the pedicelled flowers are arranged along an axis. They are flowers that present homologous pieces, at the same level of the floral axis, with two planes of symmetry and with well-differentiated calyx and corolla, therefore, they are actinomorphic and heterochlamid cyclical flowers.
They have a well developed perianth consisting of the calyx and corolla. The calyx, synsepal, is formed by five reddish sepals welded together; the corolla, dialysépalous, has five free petals equal to each other, arranged symmetrically in a very regular way, white or pale pink in color and welded only at the base. The entire flower is found around an open, concave receptacle called a hypanthium.
The androecium is formed by the set of male organs of the flower called stamens. These are formed by a filament and an anther that is made up of two thecae. In each theca we can find two pollen sacs where the pollen grains are.
In the flowers of the almond tree the number of stamens is high, between 15 and 30, arranged in several groups and without being welded between them: they are polyadelphos and free stamens. These are located irregularly in front of the petals and sepals, and do not protrude from the corolla, they are even stamens. The opening process of the anthers is done by a slit along each theca, a process called longitudinal dehiscence.
The gynoecium is the female sexual apparatus of the flower and is formed, in this case, by a single free carpel located within the hypanthium and covered with white hairs. Inside this we find a closed cavity called the ovary located above the rest of the floral pieces. Therefore, we will say that the almond flower is monocarpelar. In addition, it is also perigynous because it has sepals, petals and stamens distributed around the gynoecium. Its placentation is marginal, that is, the seminal primordia are inserted at the margins.
Once fertilization occurs, the fruit is formed in the ovary that contains the seeds and contributes by dispersing when they are ripe. They are simple fruits, since they come from a monocarpelar gynoecium. If we compare the fruit of the almond tree, which is an ovate and tomentose drupe (covered with hairs), with that of other fruit trees that are classified in the same genus Prunus (such as plum, cherry, apricot and peach trees) we can see the similarity between the almond and the stones of the plum , the cherry , the apricot and the peach .
The difference is that the mesocarp, which in these fruits constitutes the fleshy part, which is what is eaten, in the almond tree is a kind of skin that dries out during maturation and opens releasing the bone with the seed inside, the almond, which will be the edible part in this case. The almond has a stony endocarp that is reddish brown when the seed is well ripe and the opening of the fruit is not of a certain shape, it is indehiscent.
The almond stones are also much smaller, proportionally, but this is largely due to artificial selection to increase the volume of the usable part, which has sought to increase the size of the almonds and reduce the size of the bones of the others. fruity. Of these fruits, the one that most resembles the almond tree is the apricot, which does not open by itself but can be opened very easily by a very visible suture and separate the stone.
The fruit of the almond tree is the almond, that is, the seed. It contains 2.3% carbohydrates, 5.7% water, 15.2% cellulose, 18.7% protein and 58.1% fat. It is also rich in vitamin B, D and minerals such as iron, magnesium, calcium, phosphorus, potassium and zinc. Both varieties of almonds, both bitter and sweet, contain the glycoside amygdalin, which has a very bad taste. Both contain ferments called emulsin, which can break down amygdalin and synthesize hydrocyanic acid.
Keep in mind that sweet almonds contain sugars , and therefore diabetics and those who take drugs or according to what medications that modify the amount of sugar should monitor the amount of almonds they take. Due to the same fact, it must be taken into account that they have a high energy value, and can cause weight gain (every 100g of almonds contains about 2160J).
With the chopped almond, sauces are made and it is used as an ingredient for bites in many dishes and stews. Raw almonds can also be added whole to some casserole meat dishes.
They are used for the musician’s dessert. Sweet raw almonds kneaded with sugar form marzipan and nougat, a typical Christmas dessert. If the almonds are chopped with sugar, forming a homogeneous mass to which water is added and then the liquid is strained, the almond horchata is created. They are basic in cakes, bitters, buns and other sweets.
Liquors can be made, for example amaretto, synthesized from bitter almonds, or hazelnut horchata. Almond milk can be used as a substitute for cow’s milk, as it is also very rich in calcium.
According to some popular cultures, it can be used as an aphrodisiac food.
Different parts of the plant have always been used as antitussive, hypotensive and hepatoprotective, among others. Its main properties are those of dermatological emollient, laxative, anti-inflammatory, healing and antispasmodic (bitter variant oil). Almond milk and oil have also been used, as an external application, for skin care.
In current medicine, almond oil is used for the treatment of dermatitis, dry skin, psoriasis, for constipation and superficial burns. The oil of the bitter variant is antispasmodic in small doses, but always under medical prescription due to the toxicity of the plant. In addition, almond milk has a dietary application due to its high nutrient content.
Possible allergies, toxicity or other negative effects of almonds
There is a variant of this species called bitter, almonds are bitter and toxic due to their high content of cyanogenic heterosides, that is, hydrocyanic acid (one milligram per almond). The fruit of the almond species is predominantly sweet, but a few bitter almonds can be found on each tree.
The bitter almond is slightly wider and shorter than the sweet almond and contains half the fixed oil of sweet almonds. It also contains the enzyme emulsin, which, in the presence of water, acts as a soluble glycoside called amygdalin that gives glucose, cyanide, and essential oil of bitter almonds, which is practically pure benzaldehyde. Bitter almonds provide 4-9 mg of hydrogen cyanide per almond.
Bitter almond extract has been used medicinally but even in low doses the effects are severe and in large doses it can be fatal. Intoxication is caused by the ingestion of 25-30 bitter almonds and produces nausea, vomiting, hypothermia, suffocation, etc. In the most serious cases, it can lead to death, especially in children. Other bitter almonds, however, are not toxic and are often used in gastronomy, especially for desserts and liqueurs.
Almond allergies are quite common , and cause swelling of the lip, face and can even close the throat.
The almond tree is native to West Asia and Northeast Africa, where it is grown wild. Although today it is found throughout the Mediterranean area, extended to Iran, in North America and in the Far East.
It is a tree that adapts well to light, dry and rocky soils, preferring calcareous soils, and lives in temperate climate zones, with hot, dry summers and mild winters with few frosts. On the contrary, it is difficult for it to survive in humid and impermeable lands and in cold environments. Frost, gummosis, shriveling, root rot in humid areas and the almond caterpillar hinder its growth and can cause death.
It is a plant that is multiplied by grafting on a bitter almond rootstock, since it is more resistant. The most cultivated varieties are: Atocha, considered a Spanish variety with high quality almonds; Fainting Largueta: Fainting red, another Spanish late flowering variety; Marcona; guara; .. There’s a lot.
Plagues and diseases
Insect pests include :
- The caterpillar of the almond tree that feeds on the youngest leaves.
- single-stranded monastery
- Malacosoma neustria that feeds on young leaves, as well as shoots and buds.
- Almond weevil (Scolytus amydali Guérin) that make holes and galleries in the bark.
- Anthonomus amygdali Hust is a beetle that attacks the centers of flowers.
- as well as the «cochineals».
Among the fungi, the most important are Armillaria, Wilsonomyces carpophila, canker and moniliosis.
There are more than fifty.
- Of early flowering the best known are: Desmayo llargueta, Marcona Garrigues, Vivot and Pozo de Felanitx.
- Late – flowering among others: Cristo morto, Texas, Ferragnes, Ferraduel, Pozo, Masbovera, Glorieta and Francolí and late-flowering and self-compatible pollen: Guara
Robert Asprin, APD is a non-dieting Accredited Practicing Dietitian passionate about inspiring positive changes in eating and lifestyle behaviors to help improve health while nurturing relationships with food and body.