Almond (lat. Prunus amygdalus) is a woody plant from the rose family (Rosaceae), and the fruits it produces, despite popular opinion, are not nuts (peanuts, pistachios, hazelnuts, walnuts, chestnuts) but stone fruits. Thus, the almond is a relative of the plum, cherry, apricot and peach.
Almonds originate from Iran, although throughout history they have spread throughout the world, especially in the Mediterranean and California, which is today the largest producer of almonds in the world. More than 2 million tons of almonds are produced annually in the whole world. In our country, it is grown in coastal Croatia, and late blooming varieties are also grown in some continental areas.
Almonds have always been valued for their positive effects on the human body, and this is also the case in Croatia, where they have practically become part of the daily diet. Therefore, it is not surprising that in addition to the name almond, we also find many other names for it, such as: bajam, mendula, mindul, omiendul, etc.
The almond plant is a perennial tree that grows to between 4 and 9 m, and when in bloom it is recognizable by its white-pink flowers. Almonds are also known for their strong roots, which can grow up to 6 to 7 m radially from the crown during the 15 years of the tree’s life.
As a rule, it is divided into bitter and sweet almond, where only the latter is used as a foodstuff.
Types of almonds
As we mentioned, almonds are basically divided into bitter and sweet almonds.
Bitter almond
It is not suitable for consumption, because it has not only bitter, but also poisonous fruit. When the fruit is broken, the smell of benzaldehyde and hydrogen cyanide is felt, and it is precisely this that gives the bitter almond its healing properties. Namely, bitter almond can be mixed with water and enzyme emulsion and in this form can be used as a sedative. However, an adult may consume a maximum of 6 g of bitter almonds processed in this way.
Sweet almond
Sweet almond is an almond that we all know and regularly consume. Sweet almond fruit is rich in proteins and unsaturated fats, but also in potassium, calcium, phosphorus, zinc, iron and vitamins E, B1 and B2. In the rest of the article, we will concentrate on this type of almond, and we should start with varieties that are extremely successful in Croatia.
Aromatic almond
This is a variety that has its regular fertility and ripens in the summer months, more precisely at the end of August, while its flowering is earlier. The aromatic almond tree is medium lush, while the fruit is medium weight (about 3.5 g) and has a semi-soft peel. For this variety of almonds, fertilization by pollinators is necessary, and Tuono, Troito, Ferragnes and Primorski are used.
Ferragnes
A high-yielding variety that ripens at the beginning of September and has earlier flowering. The Ferragnes tree is medium-sized and produces medium-sized fruits (about 3.5 g) with hard skin. The core of the fruit has a light brown skin, and this variety is usually used in the candy industry. Tuono and Ferraduel pollinators are used for fertilization.
Tuona
A high-yielding variety that ripens at the end of August. The tree itself is extremely lush, while the fruit weighs about 3.8 g and has a semi-hard shell. The fruits are useful in the candy industry and have an attractive appearance. Tuona is a self-fertilizing variety, but it can also be done with the help of Ferragnes.
Genco
An almond variety that has a medium fertility and ripens in the first part of September, while the flowering is late. The Genca tree has a medium luxuriance, while the fruits have a hard peel. The fruits themselves have an attractive appearance and are very often used in the food industry. Genco is a self-fertilizing variety.
Texas
Texas has good fertility and ripens in the first part of September and has late flowering. The tree is lush and the fruits have a semi-hard peel. The kernel itself is partially bitter, so it is often used in the candy industry, especially for making candies.
Ferrastar
It is a French variety characterized by lush and upright growth, as well as good fertility. The ripening time of this variety is medium early, and it bears oval fruits that weigh about 3.7 g. An important part of this almond variety is that it is resistant to diseases, but equally the fact that it is very lush and blooms late.
Ferraduel
Another French variety that appeared on the market only at the end of the 60s. The variety is medium-growing, but the fertility is abundant. Ferraduel blooms late and needs pollinators to grow (Ferragnes, Texas and Tuona are recommended). It has slightly larger fruits weighing up to 4.7 g. The variety is also a good pollinator for other almond varieties, but it is also important that it is resistant to monilia.
Apart from the listed varieties that thrive in our area, it is possible to find several other varieties such as:
- Non Pareil
- Fra Giulio Grande
- Maritime
- Marcona
- Nikitsky
- Crimean
- Prince Črnomir
- Tsarski is late
Almond cultivation
Although the almond tree is very grateful for maintenance, planting and propagation by seed causes the need to restore old plantations, which includes clearing degenerate, exhausted and old trees, grafting and rejuvenating old trees and young ones with new varieties that bloom later and produce more regularly. Late blooming varieties require agricultural techniques, regular pruning and fertilization.
Rejuvenation is recommended to be done in early spring by cutting off all skeletal branches of old trees, except for the so-called valve – one branch that will take over the nutrition of the root system and prevent root suffocation.
Matching cultures
Almonds are often a feature of gardens, and usually other crops are arranged around the tree. It is recommended to plant clover, comfrey, catnip, garlic, nettle and spices such as sage under the almonds. It is recommended to avoid planting potatoes and tomatoes under almonds because the plants draw nutrients from the soil that are also needed by the almond, so there is a possibility that the almond will “suffocate” them.
Watering
Almond is a very grateful plant that tolerates drought well. However, in order to increase the fertility of the plant, irrigation is advised. Namely, in order to ensure a high yield, it is important that the almond has a sufficient amount of precipitation at the time of intensive growth of vegetative and generative organs. Irrigation avoids this potential difficulty and the yield of the fruit tree can be raised up to 40%.
Fertilization
In order to carry out the correct fertilization of almonds, it is necessary to make an analysis of the soil and the leaves, but the rule is that it is carried out three times a year. Basic fertilization is carried out in the autumn months together with tillage, and then phosphorus and potassium are added to the soil. It is necessary to use fertilizers that have higher amounts of these elements, ie 100 – 120 kg/ha. Every third year, it is necessary to fertilize with organic or manure.
Fertilization of almonds is carried out in the spring months with nitrogen fertilizers. In the case of young fruit trees, top dressing is carried out at the time of crown formation in the ratio of 150 – 200 kg/ha, and in highly fertile and irrigated plantations the ratio is 100 – 200 kg/ha.
Propagation
Most almond cultivars cannot be propagated by seed. The seeds of some hybrids are sterile, while the seeds of other varieties of almonds may be viable but will not produce fruit. Therefore, the most common methods of almond propagation are taking cuttings from soft wood or grafting buds.
Propagation by cuttings
Almond propagation by cuttings is propagation in which the young shoots of the woody plant are cut off and forced to take root. In the spring, after the almond tree has leafed out and produced new shoots, select a few young, pliable shoots for softwood cuttings.
Before you cut off the shoots, prepare a container with a mixture of compost and soil. Use a pencil to poke holes in the ground for the cuttings. Also, have rooting hormone on hand. With a sharp, sterile knife, cut off the young shoots you have chosen for almond propagation just below the leaf node. The selected shoots should be about 7.5 – 10 cm long. Remove any leaf buds or leaves from the lower half of the cutting. Following the directions for the rooting hormone you are using, apply it to the bottom of the cuttings, then place them in a pot of soil. Firmly tamp the soil around the cuttings and water them gently but thoroughly.
Softwood cuttings usually take 5 – 6 weeks to root. During this time it is very important to keep the compost or potting mix moist, but not too moist. Placing the cutting in a greenhouse or clear plastic bag can help maintain consistent moisture.
Propagation by buds
Another common method for almond propagation is bud grafting. With this form of tree grafting, the almond buds you want to grow are grafted onto a compatible tree rootstock. Rootstocks of other almonds can be used for budding almond trees, as well as peach, plum or apricot trees. Budding is usually done in late summer.
With careful cuts with a grafting knife, the almond buds are grafted onto the selected substrate in one of two ways, either T-bud or chip/shield bud. With T-budding, a T-shaped cut is made in the substrate and an almond bud is placed under the bark of the cut, then secured with grafting tape or thick rubber. In shield budding, the shield chip is cut from the substrate and replaced with a properly adhered shield chip containing the almond bud. This bud is then secured in place with grafting tape.
Transplantation
In general, transplanting mature trees is not recommended. This is because the larger the tree, the more of the root system will be damaged when it is dug out of the ground. An imbalance between the roots and aerial parts of the tree may mean that the leafy parts of the tree may be seeking water that the disturbed root area cannot handle. The tree then suffers from drought stress which can lead to the wilting of the tree.
Ground
Like all fruit trees, almonds prefer full sun and well-drained soil. The almond tree thrives in a variety of soils from sandy loam to sandy clay, but generally prefers light, fertile, deep and well-drained soils. Although the almond tree is drought-resistant and can survive for many years in dry soils, production is significantly reduced in such conditions. Low soil moisture at the end of the growing season is less critical than at the beginning.
Heavy or poorly drained soils should be avoided, as they have been shown to reduce production and favor the spread of various fungal diseases. Soil pH is usually not a limiting factor, as the tree can grow well in a pH range of 5.5 – 8.5. However, most professional almond growers correct the soil pH to 6.5 – 8.
Climate
The almond tree thrives in warm and dry climates, but has certain needs for cold weather and therefore cannot be grown in tropical climates. Given that they bloom very early compared to other fruit trees, during this period they can be damaged by frosts, which is the main limiting factor in almond cultivation.
Low winter and spring temperatures and very high summer temperatures inhibit growth and fruit set. During flowering, temperatures below -4 °C for half an hour or longer can cause serious damage, depending on the variety. On the other hand, very high summer temperatures with low soil moisture can lead to almond shrinkage.
The needs of almonds in the cold (to break bud dormancy) are small, about 250 – 350 (and in some cases over 500) hours of exposure to a temperature lower than 7°C. This is why the almond blossoms earlier than most fruit trees and thrives in areas with mild winters. Long and warm vegetation favors fruit ripening. Frequent rainfall and cold weather during flowering worsen the cross-pollination activity of bees, resulting in reduced egg laying and production. Moreover, precipitation and wet conditions favor the development of fungal and bacterial diseases, and thus decrease production. The highest yields are often obtained in irrigated almond orchards located in areas with long and hot summers, without much rainfall.
In our climate, it is possible to plant almonds up to a height of 600 m above sea level, although in practice it is possible to see that in some areas they thrive at twice the altitude.
In order for the almond to develop well, it needs a lot of light and warmth during the fruit ripening period. Considering that almonds bloom at the beginning of the year, it is not possible to plant them in areas that are abundant with frost at that time.
Also, strong and cold wind can damage the flowering, so in the case that the beginning of the year in the Dalmatian areas is full of storms, a lower fertility can be expected. Once the almond flowers have opened, they can only withstand temperatures down to -2°C, while they have no problem with high temperatures and can withstand temperatures up to 50°C. Let’s note that in a state of rest, the almond tree can withstand temperatures of up to -20°C.
Almonds are also called “kings of dry areas” because they are more resistant to drought than many other fruit trees. Namely, almonds start vegetation earlier and their organs finish growing earlier, so using winter moisture, i.e. its own reserves, it manages to fully develop before the beginning of the dry season. As a rule, almonds can grow very well in areas with only 500 mm of annual rainfall, but for its better development, irrigation is always advised. Nevertheless, in our country, irrigation of almonds is not a common practice, but it should be kept in mind that with irrigation “drop by drop” it does not bring excessive costs, but it brings a safe crop.
Light
The results of a six-year study conducted by University of California (UC), Davis scientists found that light interception is a determining factor in how much fruit an almond tree will produce. Individual plants rarely bear fruit in the following two years, and their productivity and the location of the spur affects the subsequent harvest. It was discovered that the spurs must be in the light to bear fruit. Strong shading in the crown can lead to the death of a larger part of the tree.
Planting almonds
When planting almonds, it is important to use only healthy, high-class seedlings. It is recommended that the seedlings be placed in the prepared soil at a distance of 6 x 4 m, especially if it is about plantations in which there is no irrigation. In the case of irrigation, it is also possible to place the seedlings at a distance of 6 x 5 m.
Planting time
As a rule, almonds are planted either in autumn or spring. Those fruit growers who decide to plant in spring should prepare the soil between summer and winter depending on soil moisture, while fruit growers who want to plant almonds in autumn should prepare the soil during the summer months.
Choosing the substrate for planting
In our area, it is possible to use different substrates for growing almonds, such as peach, almond and plum substrates. The choice mostly depends on the chemical composition of the soil on which planting is planned. Our fruit growers mostly use bitter and sweet almond seeds, which tolerate dry, stony and carbonate soils well, while in this case the active lime content should reach a maximum of 15%. Fruit growers who choose to plant on bitter almond seedbed can expect lush growth of their trees as well as good fertility, and trees planted on this substrate will also be drought resistant.
If the soil on which you plan to plant almonds is loose and lighter, it is recommended to grow on peach seeds. For this substrate, the content of activated lime should not exceed 5%. Fruit trees planted on this substrate will have lush growth and will be resistant to drought.
It is not possible to use almond and peach rootstocks on carbonate soils because both rootstocks are susceptible to viruses. We also emphasize that if the content of active lime in the soil is between 5 and 12%, it is recommended to plant almonds on a substrate that is a cross between almonds and peaches (GF 677). This type of rootstock will be more successful in drought tolerance than the peach rootstock.
Planting from seeds
In our country, various types of almonds are propagated by sowing the plant from seeds, which leads to unstable and low production, because young buds and flowers are called due to early flowering. Although the objective conditions and possibilities for a significant expansion of almond cultivation in Croatia are good, growers are most often faced with the problem of fruits with poor quality, precisely because of generative propagation (from seeds). The trees reach different development and age, and the crowns are shaped freely. The kernel yield ranges from 25 to 30%, which is why the almonds taste bitter, and mostly those with a harder shell prevail, which requires the renewal of old plantations so that late-blooming varieties produce regularly.
Planting seedlings
Autumn is the ideal time for planting almond seedlings, so that the tree can begin to develop even before the beginning of the growing season in spring. Late winter to early spring is the next best option for planting seedlings. However, pot-grown trees can be planted outdoors at any time of the year.
Dig a planting hole wide enough for the roots to spread out. Make sure the top of the root ball is level with the soil, well established, water and mulch the soil with compost or shredded bark to improve moisture retention and prevent weed growth. Tie the tree to a short stake at a 45° angle.
Cultivation in the garden
After planting the seedling outdoors, during the first year be sure to water the tree during dry periods, thoroughly every few days to encourage the development of deep roots. Clean the ground around the base of the tree from grass and weeds. Ideally, apply a mulch of rotted compost, 5-8 cm thick, over the area where the tree is taking root. Harvest almonds in mid-autumn. When the shell starts to crack, it is a good sign that the nuts are ripe.
Cultivation in a greenhouse
Almond trees prefer to grow outside, outdoors where they require minimal care. However, they are easily damaged if temperatures drop below 10°C, so if you live in areas with cold climates, it is recommended to grow a seedling (from seed) in a greenhouse until the plant has developed strong roots.
Cultivation in containers
It is not recommended to plant the almond tree in containers because the almond tree has its own purpose – the development of fruits that are used as food. For fruit development, the tree must reach a certain height and age. However, you can grow an almond tree in containers, just remember to provide it with a large enough container for development and growth, and after 3 years, you might get some fruit.
Maintenance and care
Almond tree care varies depending on the season. In winter or during the dormant season, growing almond trees should be pruned (December/January) to encourage growth, allow light and remove any dead or diseased branches. Clean the area around the tree to prevent an infestation of overwintering orange worms and spray with oil.
Selection of breeding form
When growing almonds, it is very important to choose the right cultivation form. If you are planning to engage in intensive cultivation, it is recommended to use several forms of cultivation, both flat and spatial. For example, in Spain and California, the cultivation form of the vase is most cultivated, in Italy the repaired pyramids and vases, while the regular palmetto with characteristic slanting branches is used less and less.
Research has proven that the growing form of regular palmette with slanting branches has disadvantages – in the first years, long one-year shoots develop, and at the time of full bearing, its vegetative growth significantly weakens, which means that its true genetic potential is not exploited. It is also more difficult and expensive to shape the canopy, and difficult conditions appear during mechanical harvesting.
Based on the opinion of experts and growers with many years of practice, it is recommended to grow almonds in the form of a repaired vase.
Pruning
The almond naturally forms a pyramidal crown consisting of a conductor and several basic branches. However, in order to increase fertility, it is necessary to form a crown that will have a vase as a growing form. It is a free form of a bowl-shaped crown that has 3-4 freer branches that develop in space.
Pruning almonds should be strong, that is, it is necessary to ensure the transparency and lighting of the crown. It is carried out either during the winter or during the summer months. Winter pruning serves to remove dry or dead branches, while summer pruning is carried out to remove branches that enter the very interior of the crown or branches that are stronger than the primary branches.
We also note that in order to enable mechanical harvesting, the trunk should be kept at a height of about 1 m at the very beginning.
Harvest
Almonds begin to bear fruit in the second or third year after planting, and you can expect their full bearing after the 8th year.
The harvest time itself depends on the variety you have chosen, but as a rule it takes place from mid-August to mid-October, and the fruit tree is ready for planting at the moment when the green shell of the fruit bursts. It is important to know that the fruits do not ripen at the same time, because the fruits on the outer parts of the crown ripen first.
Almond picking is traditionally done by hand, especially in smaller orchards, but it is also possible to use shakers, i.e. machines for picking cherries and olives.
Storage
After harvesting, it is necessary to clean the fruits and dry them. Almonds are stored in a well-ventilated place with a relative humidity of 75% and a temperature of 8-10°C.
Diseases
On the basis of detailed research carried out in the area of Central Dalmatia during several growing seasons, it was discovered that almonds are most affected by fungal diseases and pests.
Monilinia
Drying of saplings and burning of flowers (lat. Monilinia spp.) on almonds are caused by Monilinia fructigena and Monilinia laxa, and this by direct damage to the flowers, which significantly reduces the fruit yield. Symptoms are visible in the sudden drying of young shoots and saplings with flowers. After flowering (or even during flowering), the flowers wither (turn brown) and dry with the affected part of the shoot. The so-called can also appear. “cancer-wounds” – drops of resin on perennial branches.
Preventive measures require the destruction of shoots that have dried up, the so-called mechanical removal – a cut of 10 to 15 centimeters below the part that is infected. Chemical treatment is carried out in autumn and early spring with preparations based on copper. In the time of full flowering, the use of Signum is recommended. It is also necessary to treat the fruit tree with blue or red oil before the growing season, and then before flowering with Merpan WP, Thiodan E-35 or Chromovita. Against monolinia, Ronlinan is also applied during full flowering.
Leaf hollowness
Leaf pitting (lat. Stigmina carpophila) causes the infection of fruits or buds that deform, dry and fall off, and gummy discharge, purple lesions on shoots and spots with a darker edge can often be observed.
For remediation, it is necessary to make a mechanical cut and destroy the infected parts. Preventive measures for leaf fall are copper-based preparations, as well as chemical protection Signum after two weeks. Leaf hollowness is prevented after petal fall, with the pesticides Chromodin S-65, Atac E-35 and Chromovit.
Orange leaf spot
Orange leaf spot (lat. Polystigma fulvum) is a common fungal disease that appears exclusively on leaves in the form of yellowish spots that first turn orange, then red and brown.
Protection against diseases includes the use of fungicides from the end of April, but in Croatia there is no registered fungicide or preparation for the prevention or prevention of disease occurrence.
Rust
Almond rust (lat. Tranzschelia discolor) is a disease that can be observed on infected leaves in the form of yellowish spots on the face of the leaf, while small brown clusters appear on the reverse side, which turn black after the end of summer.
Protection must be applied as soon as the first symptoms appear. Given that there are no registered preparations, it is allowed to use sulfur-based preparations (Microthiol Special Dispress and Cosavet DF) which are used to control powdery mildew.
Leaf curl
Almond leaf curl (lat. Taphrina deformans) appears during the creation of favorable conditions for the growth and development of parasites (rain). The symptoms are manifested on the leaves in the form of curling, and the infected part of the leaf is often deformed and purple-reddish in color, which dries up and falls off.
Preventive measures include autumn and early spring spraying with a preparation based on copper, and after the leaf buds open, preparations based on ziram are used. Curling is prevented during leaf fall or with the help of Chromovite or Nordox.
Anthracnose
Anthracnose (lat. Collletotrichum acutatum) is a fungal disease that causes changes similar to Monilinia. Symptoms appear on all parts of the plant, while necrosis appears on the leaves, saplings wither, and spots and discharge appear on the fruits, and they become mummified and deformed.
Protection includes the mechanical removal of all infected fruits and saplings and their destruction outside the yard. For chemical control, Signum is recommended during and at the very beginning of flowering, and if the rainy period is prolonged, chemical control must be repeated after 2 weeks. There is still no registered preparation for disease control in Croatia.
Drying of shoots and buds
Drying of shoots and buds (lat. Diaporte amygdali, syn. Fusicoccum amygdali and Phomopsis amygdali) manifests itself in the spring when infected buds do not open, the bark starts to turn brown, and the shoots dry out. Necrosis can also occur on thicker branches and causes the characteristic appearance of resin. The plant is most often infected in the fall when the leaves are falling, and if the infection occurs in the summer, you will notice the symptoms only the following year, on the leaves of elliptic or oval-shaped spots with a necrotic center, while the edges remain reddish or yellowish in color where they can form so called. pycnidia.
Protection includes mechanical removal by pruning of infected branches and shoots and burning outside the orchard. Protection also includes an autumn measure with preparations based on copper, and then when 50% of the leaves fall off. There are no registered preparations for protection.
Pests
Among the pests, the almond flower eater, thrips and mites appear most often. The biggest problem in protecting almond plantations from intensive attacks of diseases and pests is the lack of registered means of protection.
Almond flower eater
The almond flower-eater (lat. Anthonomus amygdali) is a tiny weevil that is very difficult to notice in the plantation. It is reddish to dark brown in color and has a white stripe on the cover. The female lays eggs in the flower bud, after which the larva develops and feeds on the contents of the bud. Its presence is often noticed only after more serious damage has been done.
Thrips
Thrips (lat. Taeniothrips meridionalis) is a pest whose appearance is noticed at the time of flowering when the flowers wither and hang, dry, and parts of the calyx and fruiting body become necrotic. Between the withered petals, you can easily spot a small, fast-moving, dark-colored insect.
Mites
Mites (lat. Tetranychus spp., Panonychus spp.) whose attack symptoms can be observed on the leaf during July when the leaves take on a silver color, and on the reverse side there is a large number of these pests that suck plant juices from the leaf. During August, signs of necrosis appear on the leaves and defoliation occurs. You can treat them with the registered preparation Calypso SC 480.
Use of almonds
Almonds contain all important items of human nutrition: proteins, carbohydrates and fats. The latter is especially important because almonds contain more than 60% oil, so they are considered a high-energy food. However, the almond kernel does not contain cholesterol or gluten, so it is suitable for preparing meals for people who are intolerant to gluten.
Preparations
Cookery
In the household, almonds are used as a snack (that is, a great substitute for unhealthy processed snacks), in cakes in ground form, but increasingly also in the form of milk. Namely, almonds just need to be soaked in water overnight, then in the morning remove the skin and mix together with water, sweeten as desired, and can be consumed in this form as an addition to coffee or as an independent drink.
Medicine
Due to its positive properties, almonds have a wide range of applications, especially from the medical side. Consuming 60 – 90 g of almonds per day reduces blood sugar levels, while the vitamin E found in almonds acts as an antioxidant. In addition to the above, almonds help with heartburn, improve brain functions, prevent the formation of gallstones, and some claim that they help with weight loss.
Interesting things
It comes from Central Asia and is known to have been cultivated in Pakistan, India, Syria and Turkey. From the Mediterranean area, it spread to the areas of North Africa and Europe, and in the 18th century, missionaries brought the almond plant from Spain to the USA, where California became one of the main areas for almond cultivation. Today, it is most commonly grown in Portugal, Iran, Morocco, Spain and Italy.
Almonds have beautiful trees that, due to the beauty of their flowers, often decorate yards as an ornamental plant. It is a favorite of birds and rodents, and considering that it blooms early and there is a danger of frost and fruit destruction, it is most often grown in coastal areas where the climate is warmer.
Along with peanuts, pistachios, hazelnuts and walnuts, it is one of the more popular healthy “snacks” today.
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