Technical articles, field findings and company updates.
Fast growth is not built with urea alone. The best fertiliser is the one that delivers nitrogen, phosphorus and potassium to the roots by correct placement; on trees, Farkesht does that with the Chalkood Cake.
Potash is a source of potassium: the element of fruit quality, water regulation and heat tolerance. In Iran, potassium sulphate is usually safer than the chloride, and it should be split from fruit set until just before ripening.
Phosphorus does not move in Iran's calcareous soil. Its benefit is roots, flowers and seed, and its timing is placement close to the roots; a surface spread of superphosphate usually has no effect.
In Iran's calcareous orchards, iron is not scarce in the soil; it is absent from the soil solution. pH, the type of chelate, the ortho-ortho isomer and spring timing decide whether the yellowing of young leaves reverses.
Use tree shade, irrigation timing and sponge-like soil to design an Isfahan or Shiraz yard for the heatwave, so plane trees and pomegranates come through summer without severe scorch.
Diversify farm income with windbreaks, livestock shade and almond, pistachio or pomegranate grown between crops, and cut soil erosion in Iran's dry climate; firewood is not the point.
In the pistachio orchards of Rafsanjan and Sirjan, saline water, excess boron and shortages of potassium and zinc appear together. The nutrition programme has to be written against the irrigation EC and the soil's lime, not from a generic prescription.
For a small yard in an Iranian city, choose pomegranate, fig, olive, quince and columnar apple over broad-crowned trees, so you get shade and fruit without damaging foundations and pipes.
Planting time in Iran is not uniform: in cold regions after leaf fall or in March; in hot, dry regions from late autumn to January. Leave summer out, and treat evergreens separately.
Autumn fertiliser is for the roots, not the shoots: give phosphorus, potassium and organic matter, do not give heavy nitrogen, and start any programme from a soil test of that particular orchard.
In an Iranian drought, instead of opening the tap wider, fix the organic matter, a five to eight centimetre mulch and a species suited to the climate, so the tree reaches stress and chlorosis later.
Citrus gummosis in Mazandaran and the south begins as gum on the collar. Drainage, planting depth, copper and a resistant rootstock hold the disease back; a spray alone does not cure a permanently wet collar.
Olive, mulberry, oleaster, ash, Aleppo pine and Mediterranean cypress suit the dry cities; Christ's thorn jujube and mesquite suit the south. Plant black locust only with caution and in limited numbers.
Keep trees in Isfahan and Yazd alive with deep, infrequent water at the dripline, a basin and drip lines; lawn water does not quench a tree, and Iran's water scarcity leaves no room for waste.
Little leaf and delayed bud break in almond and peach are zinc deficiency, not iron chlorosis. In the calcareous soils of Najafabad and Saman zinc is fixed; do not overdose the winter foliar spray.
Before spraying, read the trunk, leaves, roots and soil; in Iranian orchards much of the damage comes from drought, compaction and chlorosis, and an aimless spray kills the predators.
Useful mulch is five to eight centimetres deep and stands clear of the trunk. A volcano mound around the collar is a mistake. Judge wood chip, straw and gravel against Iran's wind and heat.
Grape powdery mildew in Qazvin and Fars gets worse with wrong timing and a closed canopy. Do not spray sulphur in the heat; keep the cover in place before flowering and after fruit set.
Do not apply an apple or citrus programme to the date palms of Bushehr and Bam. Boron, potassium, water quality and a properly timed leaf analysis build the crop, not scattered winter nitrogen.
Choosing between bare-root, containerised and balled-and-burlapped stock is not only about price; in the heat of Isfahan and in calcareous soil, root form and planting season decide which tree really establishes.
Foliar iron, zinc, manganese and boron work in the cool hours and with suitable water. Choose the right chelate, do not mix the tank at random, and do not abandon the soil programme.
Armillaria, Ganoderma, charcoal rot and collar gummosis threaten a tree from the roots and the butt. A fungus at the foot of a tree is a warning; advanced butt rot is not cured by spraying.
Read the salinity of orchards in Yazd and Kerman from the water EC first. Calculate the leaching fraction, correct sodic soil with gypsum, and do not treat the salt ring of a dripper as the same problem as flood irrigation.
In Chaharmahal, Azerbaijan, Hamadan and Khorasan, irrigate before the frost, whitewash the trunks of saplings, put up a windbreak, and postpone heavy pruning through the peak of the cold.
A hollow trunk, a lean towards a building, a lifting root plate or a dead crown sometimes mean responsible removal. On Iran's streets and with old plane trees, do not mistake that decision for cosmetic pruning.
Wood-boring beetles in Iran come from stress far more than from some missing pesticide. Drought, pruning wounds and bad planting are the way in; wood sanitation and irrigation come before any unjustified injection.
Gales, dust storms and the 120-day winds of Sistan test a tree at the roots and in the crown. Species, structural pruning, root space and correct staking raise resilience from Zabol to Ahvaz and Tehran.
In a calcareous orchard, dripper placement, the wetting pattern, iron and lime clogging, cautious acid flushing, pulse irrigation and the salt at the wet edge have to be seen together, not as separate lines in a programme.
Fire blight of pear and quince in Azerbaijan, Isfahan, Khorasan and Zanjan enters through the blossom and through wounds. Cut a bent shoot twenty to thirty centimetres below the symptom, and disinfect the secateurs.
A strong tree is built with a central leader, cuts at the branch collar and the removal of included bark, not by topping. Pruning a sapling differs from pruning a mature tree, and the timing depends on the species and the safety objective.
Match the scion and rootstock to the method — cleft, whip-and-tongue or T-budding — and to a window from late winter into spring. In Iran's calcareous and saline soils, the choice of rootstock matters more than the graft itself.
An Iranian summer wears trees down with heat and with lawn-shaped shallow irrigation. Deep watering, mulch, checking the drip lines, avoiding nitrogen at the peak of heat and light deadwood pruning are what the hot season really needs.
Drought usually means midday wilting and dry soil at twenty to thirty centimetres. A deficiency shows a pattern on old or young leaves and in the veins. Dig first, fertilise second.
Correct planting means the right species, a wide rather than deep pit, the collar above the soil, freed roots, the nursery stake removed, a berm, deep watering and mulch clear of the trunk — from December to March, not July and August.
Manage a veteran urban tree with proper crown reduction, not topping. Aerate the soil, do not change the ground level, assess a cavity for strength, and treat a culturally significant tree with respect.
