Nutrition (fertilizers and top dressing)

1.1 Macronutrients

These form the basis of mineral nutrition. Their deficiency immediately affects growth and yield.

Nitrogen (N). The most important element for cherries. It is a component of proteins, chlorophyll, and other vital compounds. Nitrogen is responsible for vigorous shoot and leaf growth. When deficient, growth weakens, leaves become pale green and then yellow and drop. However, excess nitrogen is equally dangerous: it provokes excessive vegetative growth at the expense of fruiting, delays berry ripening, and reduces winter hardiness (Agustí, 2010; Webster and Looney, 1996). Healthy leaves should contain 2.2–3.4% nitrogen (Hanson and Proebsting, 1996).

Potassium (K). The second most important element. Potassium plays a key role in water relations, activates enzymes, and participates in sugar synthesis. It determines fruit size, taste, and storage ability. Potassium also increases tree resistance to drought and diseases. When deficient, leaf margins yellow and dry out (“marginal burn”), and berries become small and tasteless. Optimal potassium content in leaves is 1.0–3.0% (Hanson and Proebsting, 1996). Potassium is actively taken up by fruits, so its consumption is highest during fruit growth and ripening (Westwood, 1993).

Phosphorus (P). This element is necessary for energy metabolism, root system formation, and flower bud initiation. Phosphorus affects flowering timing and fruit set quality. Phosphorus deficiency is less common, but its shortage slows growth and may cause a purple tint on leaves. Phosphorus content in leaves should be between 0.16–0.40% (Hanson and Proebsting, 1996).

Calcium (Ca). This is the “building material” for cell walls. Calcium ensures fruit firmness and density, which is critically important for storage. Adequate calcium in berries reduces the risk of pre‑harvest cracking (Hanson and Proebsting, 1996). Calcium is practically immobile in the plant, so its supply must be continuous. Leaves should contain 0.7–3.0%.

Magnesium (Mg). This element is the central atom in the chlorophyll molecule. It is responsible for photosynthesis and overall green leaf colour. When deficient, older leaves turn yellow while veins remain green (interveinal chlorosis). Normal magnesium content is 0.4–0.9% in leaves (Hanson and Proebsting, 1996).

1.2 Micronutrients

They are required in very small amounts (milligrams per kilogram of dry matter), but without them the tree cannot function properly.

Boron (B). Critically important for flowering and fruit set. It stimulates pollen tube growth and ensures fertilisation. Boron deficiency reduces yield, deforms fruit, and causes shoot tip dieback. Leaf boron should be 25–60 ppm (mg/kg) (Hanson and Proebsting, 1996). Boron is immobile, so foliar applications before and during flowering give the best results.

Zinc (Zn). Participates in auxin (growth hormone) synthesis. Its deficiency leads to “rosetting” —shortened internodes and small, narrow, chlorotic leaves. Normal zinc content is 15–70 ppm (Hanson and Proebsting, 1996).

Manganese (Mn) and Iron (Fe). Both elements participate in photosynthesis. Their deficiency shows as interveinal chlorosis (yellowing between veins). Iron deficiency starts on young top leaves, while manganese deficiency affects older, lower leaves. Optimal manganese is 20–200 ppm, iron 20–250 ppm (Hanson and Proebsting, 1996).

1.3 Nutritional Peculiarities in Different Development Periods

The tree’s nutrient needs are not constant; they change depending on the growth and fruiting stage.

Spring (bud swelling and flowering). At this time, the tree actively uses nutrients stored from the previous year. The main element is nitrogen, needed for rapid leaf and shoot growth. From bud break to flowering, boron is vital for successful pollination (Westwood, 1993; Mikheev and Revyakina, 2004).

Immediately after flowering and at the start of fruit growth. This is when the crop is formed. The tree needs potassium to form large and sweet berries. Nitrogen is needed to maintain active shoot and leaf growth that will feed the fruit. Optimal soil conditions and calcium availability during this period are critical for preventing future fruit cracking (Long et al., 2021; Westwood, 1993).

Fruit growth and ripening period. This is the most critical stage. Potassium uptake reaches its maximum because it accumulates in the berries. Nitrogen uptake must be balanced: excess nitrogen will delay ripening and reduce fruit colour (Agustí, 2010). Foliar calcium sprays are effective for increasing fruit firmness.

Autumn (after harvest). The main task is to prepare for winter. Nitrogen is not applied at this time to avoid stimulating growth that could be damaged by frost. Instead, phosphorus and potassium (the main P‑K fertiliser) are applied, which promote wood maturation, accumulation of nutrients in roots, and increased winter hardiness (Mikheev and Revyakina, 2004; Hanson and Proebsting, 1996). In dry autumn, moisture‑recharging irrigation is important to help the plant absorb these elements.

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2.1 Soil Analysis

This is your first step. Long before planting or at the start of the season, soil analysis shows its basic characteristics: type, texture, pH level, and the content of major nutrients.

Why is it needed? Soil analysis helps determine whether the soil contains the “building materials” for the tree. It shows not the actual element content in the tree, but the soil’s potential to supply them. The main thing soil analysis provides is pH level. It directly affects whether roots can absorb nutrients. Cherry prefers slightly acidic to neutral soils with pH 6.0–7.0. At pH below 5.5 or above 8.0, many elements (phosphorus, iron, zinc, manganese) become unavailable, even if they are present in the soil (Westwood, 1993; Long et al., 2021).

How and when to sample? Soil samples are taken from the root zone at a depth of 20–40 cm (where most active roots are located). For reliability, mix several samples from different points in the area. It is recommended to do the analysis in autumn or early spring, before fertiliser application, to have a “baseline.” Frequency: once every 3–4 years for a mature orchard (Hanson and Proebsting, 1996; Quero‑García et al., 2017).

Important note: Soil analysis does not give an accurate assessment of nitrogen availability because its forms in the soil are very dynamic and depend on microbiological activity. However, it is indispensable for determining phosphorus, potassium, calcium, magnesium, and micronutrient levels, as well as for calculating lime rates for pH correction.

2.2 Leaf Analysis (Foliar Diagnosis)

This is the most accurate and reliable method for assessing nutrition in perennial fruit crops, including cherry. Leaves are the “mirror” of the tree’s nutrition. Their chemical composition reflects what the tree has actually absorbed from the soil, not just what is present there (Agustí, 2010; Hanson and Proebsting, 1996).

When and how to sample? The classic timing for cherry is midsummer (second half of July – early August), about 120 days after full bloom. At this time, the concentration of major elements in leaves is most stable (Agustí, 2010; Westwood, 1993).

• Take 50–100 fully developed leaves from the middle part of current season’s shoots. Leaves should be healthy, without signs of disease or pests.
• Collect leaves from 5–10 trees of the same variety and rootstock, from all sides of the canopy.
• Dry the leaves quickly (not in direct sunlight) and send them to a specialised agrochemical laboratory.

What do the results show? The laboratory reports the content of macro‑ and micronutrients as percentages or in mg/kg of dry matter. These values are compared with generally accepted “normal” ranges for cherry (see table). If values are below the lower limit, a deficiency is diagnosed; above the upper limit – excess or toxicity.

Guideline leaf nutrient concentrations for cherry (midsummer):

Source: compiled from Hanson and Proebsting, 1996; Webster and Looney, 1996; Shear and Faust, 1980.

Why is this useful for the grower? Knowing the exact leaf composition allows you to adjust fertilisation purposefully: add only what is truly lacking and avoid overdoses. This saves money and protects the environment.

2.3 Visual Signs of Deficiency and Excess

This is your “quick test” in the orchard. The tree itself gives signals through its appearance. Learning to read them lets you notice problems in time and verify them with analysis. Remember that many symptoms are similar, so visual diagnosis is only a reason for deeper investigation, not a final diagnosis.

Nitrogen (N):

• Deficiency: Leaves become pale green or yellow, starting with lower, older ones. Shoot growth is weak, shoots thin and short. Berries are smaller and ripen early.
• Excess: Overly dark, large leaves, vigorous shoot growth, delayed berry ripening, poor colour, reduced winter hardiness. The tree “runs to wood” (Mikheev and Revyakina, 2004; Agustí, 2010).

Potassium (K):

• Deficiency: Leaf margins and between veins yellow, then brown and die (“marginal burn”). Starts on lower leaves. Fruits small, pale, poorly coloured, low sugar.
• Excess: Rare; can induce magnesium and calcium deficiency.

Phosphorus (P):

• Deficiency: Leaves dark green with purple or bronze tint. Root and shoot growth slows. Flowering and ripening delayed.
• Excess: Blocks zinc and iron uptake.

Magnesium (Mg):

• Deficiency: Typical interveinal chlorosis on older leaves: tissue between veins yellows while veins remain green. Later brown necrotic spots appear on yellow areas, leaves drop.

Iron (Fe):

• Deficiency (lime‑induced chlorosis): Interveinal yellowing, but primarily on young, top leaves. Veins remain bright green. Cause: alkaline soil pH (> 7.5), making iron unavailable.

Zinc (Zn):

• Deficiency: Small, narrow, chlorotic leaves clustered in “rosettes” at the tips of shortened shoots. Internodes severely compressed. Buds may fail to open.

Boron (B):

• Deficiency: Shoot tips die back, leaves become deformed, thick and brittle. Flowering weak, few fruit set, fruits small, deformed, may have cracks and corky spots.
• Excess boron: Leaf margins die, necrotic spots appear. Branches may die back with gum exudation.

Remember: Visual diagnostics are effective when combined with soil and leaf analysis. If you notice alarming symptoms, do not rush with root applications—first verify your suspicions through leaf analysis to avoid harming the tree.

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3.1 Compost

Compost is the “black gold” of the gardener. It is a product of decomposed organic waste (plant residues, grass clippings, kitchen waste, leaves, etc.) processed by microorganisms. It is a balanced and stable source of nutrients that does not burn roots and works as a slow‑release fertilizer (Martin, 2019; Srivastava, 2020a).

Why is this important for cherries? Compost improves the structure of even the most problematic soils. On sandy soils, it helps retain moisture and nutrients; on heavy clay, it makes them looser and more breathable. Organic matter in compost feeds earthworms and beneficial bacteria, which in turn make nutrients available to roots. Regular compost application increases tree resistance to diseases and adverse weather (Srivastava, 2020a; Long et al., 2021).

How to apply:

• Rate: For young trees (first 2–3 years), 1–2 buckets (about 10–20 kg) per tree per season is enough. For a mature bearing tree, a more generous dose is recommended: 5–10 kg per 1 m² of the trunk circle, equivalent to about 2–3 shovel‑loads around the crown perimeter (Mikheev and Revyakina, 2004).
• Timing and method: Compost is applied in spring or autumn. Spread it evenly over the surface of the trunk circle, keeping 10–15 cm away from the trunk. Then gently work it into the top soil layer (10–15 cm deep) or use it as mulch by leaving it on the surface. For cherries, compost can be applied once every 2–3 years (Mikheev and Revyakina, 2004; Quero‑García et al., 2017).
• For maximum benefit, apply compost into ring‑shaped trenches or holes dug along the periphery of the crown projection, 20–30 cm deep. This ensures nutrients reach the active absorbing root zone (Mikheev and Revyakina, 2004).

3.2 Manure (Well‑Rotted)

Manure is a traditional organic fertilizer. However, for cherries, as for most fruit trees, fresh manure is strictly forbidden. It contains too much aggressive ammonia that burns roots and may introduce diseases and weed seeds. Only well‑rotted manure (composted for at least one year) should be used.

• Why it matters: Well‑rotted manure is a rich source of all major macronutrients, especially nitrogen, as well as beneficial microflora. It stimulates soil microbial activity (Martin, 2019; Quero‑García et al., 2017).
• How to apply: Application rates are similar to compost. Manure is applied in autumn under digging of the trunk circle to a depth of 20–25 cm. Since manure contains more nitrogen than compost, use it cautiously, especially on young trees, to avoid excessive shoot growth. Optimal frequency: once every 2–4 years (Mikheev and Revyakina, 2004).

3.3 Green Manures (Cover Crops)

Green manures are plants (cereals, legumes, crucifers) specially sown in the orchard inter‑rows or under the tree canopy, then ploughed in or mown and left as mulch. This is one of the most effective and environmentally friendly ways to maintain soil fertility, especially in organic gardening (Martin, 2019; Srivastava, 2020a; Quero‑García et al., 2017).

Why it matters: Green manures perform several functions simultaneously:

• Enrich soil with nitrogen. Legumes (vetch, lupin, clover, sweet clover) form symbioses with nodule bacteria that fix atmospheric nitrogen and convert it into plant‑available forms—a free and eco‑friendly nitrogen fertilizer (Martin, 2019; Srivastava, 2020a).
• Improve soil structure. Powerful roots of green manures loosen the soil, improve air and water permeability.
• Protect against erosion and weeds. A dense cover prevents soil washing and wind erosion and suppresses weed growth.
• Create habitat for beneficial insects. Flowering green manures (especially crucifers and legumes) attract bees and other pollinators, as well as predatory insects that help control pests (Martin, 2019).

How to use in a cherry orchard:

• Choice of crops. Legume‑cereal mixtures are excellent for cherries. For example, oats or ryegrass combined with vetch or field peas. Legumes enrich the soil with nitrogen, and cereals provide plenty of organic matter for structure improvement. Important: do not use overly aggressive legumes (e.g., alfalfa or sweet clover in the first year) that can strongly dry out and deplete the soil by competing with trees for moisture (Srivastava, 2020a).
• Sowing and incorporation timing. In temperate climates, green manures are sown in late summer – early autumn (August‑September) to build up green mass before cold weather. In spring, 2–3 weeks before bud break (or at the budding stage for legumes), the green mass is mown and incorporated into the soil to a depth of 15–20 cm. Alternatively, leave the mown material as mulch, but then cover it with a thin layer of compost or soil to speed up decomposition (Martin, 2019; Mikheev and Revyakina, 2004).
• Important: Mow and incorporate green manures before flowering, otherwise stems become woody and decompose slowly.

3.4 Other Organic Materials

Bark, wood chips, straw mulch (plant residues). Mulching trunk circles with a 5–10 cm layer is a gardener’s best friend. Mulch prevents weeds, conserves soil moisture, protects roots from overheating, and, as it decomposes, serves as an additional nutrient source (Long et al., 2021; Martin, 2019). Especially effective is mulch from shredded branches (ramial wood chips), which decomposes slowly, enriching the soil with carbon and creating a favourable environment for beneficial fungi. When using mulch, do not place it right against the trunk to avoid bark rot.

Peat. Mainly used to improve soil structure, not as a fertilizer, since it is low in nutrients. It is recommended to compost it with other organic waste before use (Mikheev and Revyakina, 2004).

Bone meal and other “slow” fertilizers. Bone meal is an excellent source of phosphorus and calcium that decomposes over several years, providing long‑term nutrition. It can be applied in planting holes or in autumn under digging. Fish meal, blood meal, and feather meal are fast‑acting nitrogen sources suitable for emergency spring feeding (Quero‑García et al., 2017; Srivastava, 2020a).

Brief summary on organic fertilizers:

Regular use of organic fertilizers is the path to creating “living” and fertile soil. Unlike “fast” mineral fertilizers, organics act gently and over a long period, gradually releasing nutrients. This allows the tree to avoid stress from sharp changes in salt concentration and build a stable immune system. Compost and green manures are your main allies in the organic cherry orchard.

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4.1 Nitrogen Fertilizers (N)

Nitrogen is the main driver of growth. Its importance for cherries cannot be overstated. However, as noted earlier, its excess is as dangerous as its deficiency.

Main forms of nitrogen:

• Nitrate form (NO₃⁻). Found in calcium nitrate (Ca(NO₃)₂) and sodium nitrate. This is the most root‑available form. It is highly soluble but easily leached from the soil, especially on light sandy soils. Calcium nitrate is an excellent choice for cherries because it simultaneously supplies nitrogen and calcium, which is important for fruit quality (Srivastava, 2020b; Bryla, 2020).
• Ammonium form (NH₄⁺). Found in ammonium sulfate ((NH₄)₂SO₄) and ammonium nitrate (NH₄NO₃). This form is less mobile in soil and less leachable. However, its excess can be toxic to roots and acidify the soil. Ammonium sulfate also provides sulfur, but frequent use requires monitoring soil pH (Srivastava, 2020b; Westwood, 1993).
• Amide form. Urea (carbamide) is the most concentrated nitrogen fertilizer (46% N). In the soil, under the action of the enzyme urease, it quickly converts to ammonium and then nitrate. Urea is well suited for foliar feeding, but when surface‑applied, nitrogen losses as gaseous ammonia can occur (Srivastava, 2020b).

Application rules:

• Rate. For mature bearing cherries, the optimal rate is 60–130 kg of nitrogen per hectare per year, which per tree is about 0.5–1.5 kg of active ingredient, depending on yield and soil fertility (Hanson and Proebsting, 1996; Quero‑García et al., 2017). Rates are lower for young trees.
• Timing. Nitrogen fertilizers are applied in spring, during active shoot growth. Split application is most effective: first feeding at bud break, second 3–4 weeks after bloom, during active fruit set growth. Nitrogen is not applied in autumn to avoid stimulating shoot growth before winter.
• Method. Nitrogen fertilizers are best applied in dissolved form into furrows or trunk circles, followed by watering. With drip irrigation, they can be applied through fertigation.

4.2 Phosphorus Fertilizers (P)

Phosphorus is responsible for root system development, fruit bud initiation, and flowering energy. Its deficiency is less common, but the consequences for future yields are significant.

Main forms:

• Single and double superphosphate. Traditional phosphorus fertilizers containing water‑soluble phosphorus. Double superphosphate is more concentrated.
• Monoammonium phosphate (MAP) and Diammonium phosphate (DAP). Compound fertilizers that supply both phosphorus and nitrogen. They dissolve well and are suitable for fertigation.

Application rules:

• Peculiarity. Phosphorus is one of the least mobile elements in soil. It quickly binds to soil particles and becomes unavailable to roots. Therefore, phosphorus fertilizers must be incorporated into the soil at the depth of the main root mass (20–30 cm) or applied in the planting hole at planting (Westwood, 1993; Quero‑García et al., 2017).
• Rate and timing. Phosphorus fertilizers are applied in autumn during basic soil preparation or in spring into furrows. The rate depends on soil phosphorus availability, but on average is 60–100 kg P₂O₅ per hectare. For one mature tree, this is about 200–300 g of superphosphate. Phosphorus fertilizers can be applied once every 2–3 years because they act slowly (Mikheev and Revyakina, 2004).

4.3 Potassium Fertilizers (K)

Potassium is the “quality element” for cherries. It determines fruit size, sugar content, colour, and storage life, as well as tree resistance to drought and disease.

Main forms:

• Potassium chloride (KCl). The most common and cheapest potassium fertilizer. However, cherries, like most fruit crops, are sensitive to chloride. Therefore, on light sandy soils, its use can be risky.
• Potassium sulfate (K₂SO₄). The preferred choice for cherries. It contains no chloride and additionally supplies sulfur, which is also needed for protein synthesis. This fertilizer is more expensive but safer.
• Potassium magnesium sulfate (K₂SO₄·MgSO₄, “K‑Mag”). An excellent choice for soils deficient in magnesium, as it simultaneously supplies both elements.

Application rules:

• Rate and timing. Potassium fertilizers are applied in autumn (main application) or spring (as a top dressing). Application rate: 100–200 kg K₂O per hectare. For a tree, this is about 200–400 g of potassium sulfate. Potassium is well absorbed throughout the growing season, so it can also be applied as liquid feeds during fruit filling.
• Interaction. Remember the antagonism between potassium and magnesium: excess potassium can induce magnesium deficiency. Therefore, on soils low in magnesium, potassium magnesium sulfate is preferable.

4.4 Compound Fertilizers

Compound fertilizers contain two or three major elements (N, P, K) in various combinations. They are convenient for base application and save time.

Main types:

• Nitrophoska (NPK). Contains nitrogen, phosphorus, and potassium in a balanced ratio (e.g., 16:16:16). Suitable for base application in spring or autumn.
• Compound fertilizers with micronutrients. Modern fertilizers enriched with magnesium, boron, zinc, manganese in chelated (plant‑available) form. This is the best choice for comprehensive support of the cherry orchard, covering all major tree needs.

Application rules. Compound fertilizers are applied according to package instructions. Choose a formula that matches the period: in spring – with a predominance of nitrogen (e.g., NPK 20:10:10), during fruiting – with a predominance of potassium and phosphorus (e.g., NPK 10:10:20). For high yields, it is important to maintain balance among elements to avoid excess of one at the expense of another (Srivastava, 2020b; Bryla, 2020).

Conclusion on mineral fertilizers:

Mineral fertilizers are a powerful tool, but they must be used wisely. The main principles:

1. Determine the need through soil and leaf analysis.

2. Choose the form best suited to your soil type and growth stage.

3. Apply accurately at the right rate, right time, and right place (active root zone).

4. Do not forget about balance: excess of one element often leads to deficiency of another.

Combining organic fertilizers (for soil health) and mineral fertilizers (for precise nutritional correction) is the optimal strategy for obtaining stable and high‑quality cherry yields.

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5.1 Spring (Early, Before Bud Break)

This period is the most important for setting the future crop. The tree wakes up and begins actively using nutrient reserves stored in roots and wood from the previous year. Our task is to support this process and give a kick‑start to vegetation.

Goal: Provide the tree with readily available nitrogen for rapid leaf and shoot growth, and micronutrients for full flowering and fruit set.

What to apply:

• Nitrogen fertilizer. The main dose of nitrogen (about 60–70% of the annual rate) is applied now. Best options are ammonium nitrate or urea. For mature trees, the rate is 30–50 g per 1 m² of the trunk circle; for young trees, 15–20 g. Nitrogen fertilizers can be broadcast on the soil surface (if rain or irrigation follows) or worked into the top 5–10 cm during cultivation (Mikheev and Revyakina, 2004; Westwood, 1993).
• Compound fertilizer. If using compound fertilizers (NPK), choose a formula with a predominance of nitrogen, e.g., 20:10:10 or 16:16:16. Apply according to package instructions.
• Organics. If you did not apply compost or manure in autumn, you can do it now. But remember that organics act more slowly, so combine them with fast‑acting mineral forms.

Important: Early spring feeding is especially effective if applied in liquid form (e.g., dissolve the fertilizer in water and water the trunk circle). This speeds up nutrient delivery to the roots.

5.2 After Flowering (Fruit Set Growth Phase)

Flowering consumes a huge amount of the tree’s energy. After it ends, active growth of fruit sets and new shoots begins. This period forms the basis of the future harvest – its quantity and quality.

Goal: Support the tree after flowering, provide nutrition for fruit growth and for the formation of flower buds for the next year’s crop.

What to apply:

• Nitrogen. The remaining part of nitrogen (about 30–40% of the annual rate) is applied 2–3 weeks after flowering. This stimulates shoot and leaf growth, which will “feed” the fruits.
• Potassium. It is during this period that potassium uptake becomes active. Apply it as potassium sulfate or potassium magnesium sulfate together with nitrogen or separately. Potassium ensures future fruit size and sweetness (Hanson and Proebsting, 1996; Westwood, 1993).
• Boron and zinc. Foliar feeding (spraying on leaves) with a weak solution of boric acid (1–2 g per 10 L water) and zinc sulfate (5–10 g per 10 L water) is effective. Boron improves fruit set, and zinc promotes fruit growth (Hanson and Proebsting, 1996; Quero‑García et al., 2017).

Important: Feeding during this period is best done with liquid fertilizers (applied into furrows or as a solution), as cherry roots are actively working and dissolved nutrients are absorbed most quickly.

5.3 Summer (Fruit Filling and Ripening)

In summer, the main focus is on fruit quality. Nitrogen at this time is applied in minimal amounts or not at all, to avoid stimulating excessive vegetative growth at the expense of ripening.

Goal: Improve fruit taste, size, and colour, increase firmness and resistance to cracking.

What to apply:

• Potassium. This is the main element of summer feeds. Potassium application during fruit filling is key to sweet and large berries. Apply potassium sulfate or potassium magnesium sulfate as a solution (20–30 g per 10 L water, rate: 1 bucket per 1 m² of trunk circle).
• Calcium. Foliar feeding with calcium nitrate (1–2% solution) or calcium chloride (0.5–1% solution) 2–4 weeks before harvest significantly increases fruit firmness and reduces cracking risk during rains (Hanson and Proebsting, 1996; Long et al., 2021). Spray on leaves and fruits in the evening.
• Micronutrients (boron, manganese, iron). If needed, based on leaf analysis, conduct foliar applications of appropriate micronutrient fertilizers. This is especially relevant for cherries growing on alkaline soils, where chlorosis (iron and manganese deficiency) is common.

Important: In hot weather, carry out all feeding early in the morning or late in the evening to avoid leaf burn.

5.4 Autumn (After Harvest)

Autumn feeding is the foundation for next year’s crop and healthy overwintering. After fruiting, the tree is depleted and needs to restore strength, accumulate nutrients in roots and wood, and prepare for frost.

Goal: Improve shoot maturation, increase winter hardiness and disease resistance, and lay the groundwork for flowering and growth in the next season.

What to apply:

• Phosphorus and potassium. These are the main elements of autumn feeding. Phosphorus promotes root growth and strengthening, while potassium promotes wood maturation and frost resistance. Apply superphosphate and potassium sulfate (or potassium magnesium sulfate) in dry form under digging of the trunk circle. Dose: 40–60 g superphosphate and 30–50 g potassium sulfate per 1 m². They can also be applied as a solution into furrows (Mikheev and Revyakina, 2004; Westwood, 1993).
• Organics. Applying compost or well‑rotted manure in autumn (1–2 buckets per 1 m²) provides nutrition and improves soil structure. Work it into the soil 15–20 cm deep.
• Calcium. If needed, based on soil analysis, autumn liming (dolomite lime or slaked lime) can be done to reduce soil acidity. Apply lime separately from other fertilizers to avoid chemical reactions (Mikheev and Revyakina, 2004; Quero‑García et al., 2017).

Important: Autumn fertilizers (especially phosphorus and organic) must be incorporated into the soil, as they are immobile. Without incorporation, they will remain on the surface and be useless. In dry autumn, after fertilizer application, abundant moisture‑recharging irrigation (100–150 L per mature tree) is essential to help dissolve fertilizers and protect roots from freezing (Mikheev and Revyakina, 2004).

Brief summary of seasonal feeding:

By following this seasonal logic, you can provide your cherry with balanced nutrition at all stages of its life, ensuring stable and high yields of tasty and healthy berries.

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6.1 Soil Application

This is the classic and most common method. Fertilizers are applied directly to the soil, into the zone where the bulk of absorbing roots are located. It is suitable for both organic and mineral fertilizers.

Main methods:

• Broadcasting (surface application). Fertilizers (especially nitrogen and potassium) are scattered over the surface of the trunk circle. They are then either worked into the soil during cultivation (to a depth of 10–15 cm) or left on the surface if rain or irrigation is expected. This method is simple but has drawbacks: nitrogen (especially urea) can volatilise as ammonia, and phosphorus and potassium remain in the top layer, not reaching deeper roots (Westwood, 1993; Mikheev and Revyakina, 2004).
• Application into furrows and trenches. This is a more effective method for delivering nutrients directly to the roots. Around the crown projection (in the active root zone), dig ring‑shaped furrows 20–25 cm deep, 40–50 cm apart (Mikheev and Revyakina, 2004). Apply dry fertilizers into these furrows, water them, and cover with soil. This method is especially good for immobile phosphorus and potassium fertilizers.
• Application into holes (spot application). Along the crown periphery, drill or dig several holes (20–30 cm deep) and place fertilizers there (especially effective for organics and slow‑release forms). This ensures maximum contact of fertilizers with the root system (Mikheev and Revyakina, 2004).
• Application with irrigation (liquid root feeding). Fertilizers are dissolved in water (e.g., 1 tablespoon per 10 L water) and the trunk circle is watered. This is the fastest way to deliver nutrients to roots, especially during active growth (Mikheev and Revyakina, 2004).

When and what to apply by soil method:

• Autumn – phosphorus and potassium fertilizers, organics (compost, manure). They must be incorporated into the soil (digging or furrows) because they are immobile.
• Spring – the main part of nitrogen fertilizers, which can be broadcast (if irrigation follows) or worked into the soil during cultivation.

Key principle: Apply fertilizers not right at the trunk, but along the crown perimeter (crown projection). That is where the majority of active, absorbing roots are located. Fertilizers applied near the trunk will be largely ineffective (Westwood, 1993; Quero‑García et al., 2017).

6.2 Fertigation (Applying Fertilizers with Irrigation Water)

Fertigation is a modern and very efficient method in which fertilizers are applied through drip or micro‑sprinkler irrigation systems. This allows nutrients to be delivered precisely into the wet root zone, where they become most available to the tree (Bryla, 2020; Quero‑García et al., 2017).

Advantages of fertigation:

1. High efficiency. Fertilizers reach roots directly, significantly increasing their uptake coefficient. Losses from leaching and volatilisation are minimal.

2. Precise dosing. Allows nutrients to be applied in small but regular doses, exactly matching the tree’s needs at each growth stage.

3. Fertiliser savings. Due to high efficiency, total fertiliser amounts can be reduced by 20–50% compared to traditional methods (Bryla, 2020; Quero‑García et al., 2017).

4. Uniform distribution. Ensures even nutrient supply to all trees in the row.

What can be applied through fertigation:

• Nitrogen fertilizers. Calcium nitrate, ammonium nitrate, urea – all are highly soluble and ideally suited. Calcium nitrate is especially valuable as it supplies both nitrogen and calcium.
• Potassium fertilizers. Potassium sulfate and potassium nitrate are soluble and suitable. Potassium chloride is not recommended due to cherry’s chloride sensitivity.
• Compound fertilizers. Special liquid compound fertilizers (e.g., NPK with micronutrients) are formulated for use in drip systems.

Important rules:

• Fertilizers must be fully soluble and free of impurities that could clog emitters.
• Before applying fertilizers, flush the irrigation system with clean water.
• Apply fertilizers in small doses but frequently (e.g., weekly or every 10 days), especially during active growth and fruiting (Bryla, 2020; Long et al., 2021).

6.3 Foliar Feeding (Spraying on Leaves)

Foliar feeding is a quick way to deliver nutrients directly to leaves and other above‑ground organs. This method does not replace basic root nutrition but is an excellent supplement for solving specific problems (Agustí, 2010; Westwood, 1993).

When and why foliar feeding is needed:

1. To quickly correct micronutrient deficiencies. If leaf analysis shows a lack of boron, zinc, manganese, or iron, foliar feeding is the fastest remedy.

2. At critical development stages. For example, spraying boron before and during flowering significantly improves fruit set.

3. To improve fruit quality. Spraying calcium during fruit filling increases firmness and storage life (Hanson and Proebsting, 1996; Long et al., 2021).

4. When root uptake is impaired. For example, in cold, rainy weather when roots work poorly, foliar nitrogen (urea) can sustain the tree.

What and how to apply:

• Micronutrients. Spraying with solutions of zinc sulfate (5–10 g/10 L), boric acid (1–2 g/10 L), manganese sulfate (5–10 g/10 L), or iron chelates (according to instructions). Solutions should be weak to avoid leaf burn.
• Calcium. Spraying with 1–2% calcium nitrate or 0.5–1% calcium chloride solution.
• Nitrogen. Spraying with 3–5% urea solution (30–50 g per 10 L water) in the first half of summer is an effective foliar nitrogen feed that also helps prevent fungal diseases (Mikheev and Revyakina, 2004). Higher concentrations (5–10%) can be used in autumn after leaf fall to increase nitrogen reserves in tissues.

Rules for effective spraying:

• Time. Spray in cloudy weather or early morning/late evening to avoid sunburn.
• Temperature. Optimal is 15–25 °C. In hot weather, the solution dries quickly and absorption decreases.
• Wetting agents. Add a sticker (or simple soap) to improve solution adhesion.
• Spray both sides. Leaves absorb nutrients better from the underside, where more stomata are present. So spray generously, wetting both upper and lower leaf surfaces.

Brief summary of application methods:

Use all three methods in combination, and you will be able to provide your cherry with the most balanced and timely nutrition at all stages of its life.

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7.1 Excessive Nitrogen Application

This is perhaps the most common mistake. Gardeners, wanting to “feed” the tree, often overdo nitrogen fertilizers, especially in spring. However, for cherries, as for other stone fruits, excess nitrogen is far more dangerous than a moderate deficiency (Agustí, 2010; Westwood, 1993).

What nitrogen overfeeding leads to:

• “Luxuriant” growth. Nitrogen stimulates excessive vegetative growth at the expense of fruiting. The tree produces long, succulent shoots and large dark‑green leaves, but flowering and fruit set are weak.
• Delayed fruit ripening. Fruits on overfed trees ripen later, have pale colour, accumulate less sugar, and become watery. Taste and storage life decrease.
• Reduced winter hardiness. Nitrogen stimulates shoot growth late into autumn. Such wood does not have time to mature and harden, making the tree extremely vulnerable to winter frosts. Frost‑damaged branches and buds are a direct consequence of late nitrogen “overfeeding” (Mikheev and Revyakina, 2004; Hanson and Proebsting, 1996).
• Increased susceptibility to diseases. Excess nitrogen makes tree tissues looser and juicier, facilitating the entry of fungal and bacterial infections (e.g., coccomycosis or bacterial canker) (Long et al., 2021).

How to avoid:

• Strictly observe nitrogen fertiliser rates based on tree age and condition. For mature bearing cherries, the annual nitrogen rate should not exceed 60–130 kg/ha (about 0.5–1.5 kg active ingredient per tree).
• Apply nitrogen only in spring and early summer. In autumn and certainly before winter, nitrogen is excluded.
• If you notice signs of “luxuriant” growth (excessive shoot vigour), immediately stop all nitrogen applications and increase potassium‑phosphorus feeding to balance nutrition.
• Regularly conduct leaf diagnostics to monitor nitrogen levels.

7.2 Unbalanced Nutrition (Ignoring Element Antagonism)

The second most frequent mistake is applying one element without considering its effect on the uptake of others. Nutrients in the plant are in complex interaction. Increasing the concentration of one can cause a deficiency of another (Westwood, 1993; Quero‑García et al., 2017).

Main antagonisms:

• Nitrogen vs. potassium and calcium. Excess nitrogen hinders potassium and calcium uptake. This is especially critical for cherries, as potassium deficiency affects fruit quality, and calcium deficiency affects firmness and cracking resistance.
• Potassium vs. magnesium and calcium. Excess potassium (especially chloride) blocks magnesium and calcium uptake. Magnesium chlorosis is a direct consequence of potassium overfeeding.
• Phosphorus vs. zinc and iron. High phosphorus rates reduce zinc and iron availability. This is often a cause of chlorosis on alkaline soils.
• Boron vs. calcium. Excess boron can interfere with calcium uptake, and vice versa.

How to avoid:

• Do not apply any element without knowing its actual level in soil and leaves. Use comprehensive analysis.
• Maintain balanced ratios. For example, good potassium and calcium uptake requires boron, and magnesium uptake requires balanced potassium.
• Apply elements in chelated form (especially micronutrients) to reduce the risk of binding and antagonism.
• Use compound fertilizers with micronutrients, where the ratios of major elements are already balanced by the manufacturer.

7.3 Incorrect Timing of Feedings (Untimely Application)

The third group of mistakes relates to misunderstanding the seasonal needs of the tree. Applying fertilisers at the wrong time is not only useless but harmful.

Major timing errors:

• Late autumn nitrogen application. As already noted, this is the most dangerous mistake, depriving the tree of winter hardiness. Nitrogen applied in September‑October stimulates shoot growth right up to frost, guaranteeing their freezing (Mikheev and Revyakina, 2004).
• Spring application of phosphorus and potassium without incorporation. Phosphorus and potassium are very immobile in soil. If simply broadcast on the surface in spring, they will not reach the root zone in time and remain unavailable. They should be applied in autumn under digging or into furrows, so they are placed in the root zone (Westwood, 1993; Quero‑García et al., 2017).
• Late foliar feeding. Spraying urea (or other nitrogen fertilizers) in the second half of summer, when shoot growth should already be stopping, is as harmful as root nitrogen application. It can trigger secondary shoot growth and impair wood maturation.
• Applying lime simultaneously with nitrogen fertilizers. When liming soil (dolomite, lime), it should not be mixed or applied at the same time as ammonium‑form nitrogen (ammonium nitrate, ammonium sulfate), because this leads to nitrogen loss as gaseous ammonia. These operations should be spaced at least 1–2 months apart (Mikheev and Revyakina, 2004).

How to avoid:

• Follow the seasonal feeding calendar strictly (Chapter 5).
• Remember the golden rule: nitrogen in spring, phosphorus and potassium in autumn and early summer, calcium and micronutrients during active growth and fruit filling.
• Always incorporate phosphorus and potassium fertilizers into the soil, do not leave them on the surface.
• When planning liming, take into account its incompatibility with nitrogen fertilizers.

Final summary:

To avoid these mistakes, follow three simple principles:

1. Diagnostics first. Do not feed “by eye.” Use soil and leaf analysis to understand the real needs of your orchard.

2. Balance matters more than quantity. The tree needs a balanced “diet,” not individual “vitamins.” Consider element interactions and avoid distortions.

3. Timing is key. Apply fertilizers when the tree actually needs them, not when it is convenient for you. Synchronising nutrition with plant development phases is the basis of high yield and cherry health.