Nutrition (fertilizers and feeding)

Macronutrients

These are elements that the tree consumes in large quantities (kg/ha per year). They include nitrogen, phosphorus, potassium, calcium, and magnesium (Agustí, 2010).

Nitrogen (N) — the primary element for growth. It is a component of proteins, chlorophyll, enzymes, and nucleic acids. Nitrogen drives vigorous shoot, leaf, and large fruit development. Signs of adequate supply: dark‑green leaves, strong shoots, active growth. However, excess nitrogen is as harmful as deficiency: it causes excessive vegetative growth at the expense of fruiting, delays wood maturation, reduces winter hardiness, and impairs fruit storage life (Jackson, 2003).

Phosphorus (P) — the element responsible for energy and heredity. It participates in photosynthesis, respiration, and the synthesis of proteins and fats. Phosphorus stimulates root system development, flower bud initiation, and improves fruit quality. The pear's requirement for phosphorus is considerably lower than for nitrogen and potassium, yet its deficiency can seriously delay the tree’s entry into bearing (Agustí, 2010).

Potassium (K) — the element of quality and resistance. It regulates water balance, increases drought and frost tolerance, and improves fruit taste, aroma, and colour. Potassium promotes sugar and vitamin accumulation. The pear has a high demand for potassium, especially during fruit growth (Agustí, 2010). According to researchers, potassium uptake by a bearing orchard is nearly twice that of nitrogen (Jackson, 2003).

Calcium (Ca) — the element of structure and strength. Calcium is a key element for pear fruit quality. It is the main building block of cell walls, providing tissue firmness and rigidity. Calcium is responsible for fruit storage life, resistance to diseases and physiological disorders (e.g., “bitter pit”). Calcium movement into fruit is often limited, so special attention is paid to its balance (Agustí, 2010; Jackson, 2003).

Magnesium (Mg) — the central element of the chlorophyll molecule. It is essential for photosynthesis and activates many enzymes. Magnesium is quite mobile in the plant, so when deficient, older leaves first yellow between the veins (Agustí, 2010).

Optimal mid‑summer leaf nutrient concentrations for pear are (Jackson, 2003; Mitcham, 2007):

Micronutrients

Micronutrients are required in very small amounts (mg/kg, or ppm), yet their role in plant life is no less important. They participate in enzyme, hormone, and other biologically active compound functions.

Zinc (Zn) — a critically important micronutrient for pear. Zinc is involved in auxin (growth hormone) synthesis, so its deficiency shows sharply on young shoots: leaves become small, narrow, deformed, and cluster in “rosettes” (Westwood, 1993). Pear is very sensitive to zinc deficiency, which is common on alkaline soils.

Boron (B) — an element influencing flowering, fruiting, and fruit quality. Boron is necessary for pollen tube growth, fertilisation, and fruit set. Boron deficiency causes corky tissue and fruit deformation, cracking, as well as dieback of apical buds and shoots (“tip dieback”) (Agustí, 2010).

Iron (Fe) — participates in chlorophyll synthesis. Iron deficiency appears as chlorosis (yellowing) of young leaves with green veins. This is especially common on carbonate (alkaline) soils. Pear trees grafted on quince rootstocks are more susceptible to iron chlorosis (Jackson, 2003).

Manganese (Mn) — also important for photosynthesis. Its deficiency resembles iron deficiency but appears as pale‑green or yellow spots between veins on older leaves (Agustí, 2010).

Optimal micronutrient leaf contents for pear (Mitcham, 2007):

Nutritional Requirements at Different Life Stages

The pear’s nutritional needs change as the tree grows, enters bearing, and ages.

1. Early years (before bearing). The main task is to build a strong, well‑branched root system and form the scaffold branches. Therefore, the tree needs enhanced nitrogen and phosphorus nutrition. Nitrogen stimulates shoot growth, and phosphorus promotes root development. However, it is important not to over‑feed nitrogen to a young tree, so as not to delay entry into fruiting (Potapov et al., 2000).

2. Onset of bearing (years 3–5). This is a transitional period. The tree produces its first fruits, and it is crucial to maintain a balance between growth and cropping. Nitrogen rates can be somewhat reduced, while increasing the share of potassium and phosphorus, which stimulate flowering and fruit quality. Particular attention should be paid to micronutrients, especially boron and zinc, which are needed for flower bud initiation and normal fertilisation (Potapov et al., 2000).

3. Full bearing period. This is the peak of nutrient consumption. The orchard removes maximum amounts of macronutrients, especially nitrogen and potassium, which are exported with the crop. At this time, it is important not only to replenish the removal of elements but also to maintain an optimal balance among them. The balance between calcium and nitrogen/potassium becomes especially critical: high nitrogen and potassium in fruit coupled with calcium deficiency leads to loss of quality and reduced storage life (Agustí, 2010).

4. Senescent trees. The tree’s growth potential declines, and it becomes more vulnerable to diseases and stresses. During this period, more balanced nutrition with an emphasis on tissue strengthening (calcium, potassium) and maintenance of root system viability (phosphorus) is required. Nitrogen is applied in moderate amounts so as not to stimulate too strong growth of “rejuvenating” shoots at the expense of older but still productive wood.

Brief summary: Pear nutrition must be balanced. Nitrogen is needed for growth, phosphorus for roots and fruiting, potassium for fruit quality and tree resilience, and calcium for fruit storage life. Micronutrients, especially zinc and boron, are critical and often limit yields. Young trees are given more nitrogen, while bearing trees need potassium and micronutrients. Remember: micronutrient deficiency is no less dangerous than macronutrient excess.

Soil Analysis

Soil analysis is the starting point. It shows what is potentially available to the roots, but does not indicate what the tree actually absorbs.

What soil analysis provides:

• Acidity (pH). This is the most important indicator. The solubility and availability of almost all nutrients depend on pH. For pear, the optimal pH range is 6.5–7.5 (Mandal et al., 2021). At pH below 6.0, the availability of phosphorus, calcium, magnesium, and molybdenum decreases. At pH above 7.5 (especially on carbonate soils), the availability of iron, zinc, manganese, and boron drops sharply — these are the main causes of chlorosis and rosette leaf symptoms (Jackson, 2003; Westwood, 1993).
• Content of major elements. The laboratory determines the levels of available forms of phosphorus, potassium, magnesium, and calcium. This allows evaluation of whether the soil needs liming or additional application of these elements.
• Content of micronutrients. On alkaline soils, iron, zinc, and manganese are often deficient. Soil analysis for these elements confirms or rules out a deficiency.

How to take a soil sample correctly:

1. Samples are taken before fertiliser application (in spring before feeding or in autumn after harvest).

2. In the orchard, select 5–10 points evenly distributed over the area, avoiding tree‑trunk circles where fertilisers have been applied.

3. At each spot, take samples from a depth of 20–40 cm (the main root zone). Use an auger or spade.

4. Mix all samples into one composite sample (about 500 g) and send to the laboratory.

Important: Interpreting soil analysis results without considering regional characteristics and laboratory methods is difficult. It is best to contact local agrochemical laboratories that use methods adapted to your soils (Hochmuth and Sideman, 2023).

Leaf Analysis

Leaf analysis is the most accurate diagnostic method for perennial fruit trees. Unlike soil, leaves show what the tree has actually taken up, not just what is present in the soil. Leaves integrate all factors: soil nutrient availability, root activity, weather conditions, and the tree’s own status (Agustí, 2010).

Why leaf analysis is preferable to soil analysis for pear:

• The root system of a fruit tree permeates a large volume of soil, and a single soil sample may not reflect actual nutrient availability.
• The nutrient content in leaves is directly linked to physiological processes in the plant and correlates better with yield and fruit quality (Jackson, 2003).

Leaf sampling rules:

To ensure reliable results, sampling guidelines must be strictly followed.

1. Timing: In temperate zones — late July to August (period of relative leaf composition stability). In southern regions — July to early August (Agustí, 2010).

2. Sampling site: Take leaves from the upper or middle part of current‑season shoots (extension shoots), about 1.5–2 m above ground, from all sides of the tree (Mitcham, 2007).

3. Leaf selection: Collect medium‑sized, well‑developed leaves from non‑fruiting shoots. Avoid leaves with disease symptoms, damage, or mechanical injury (Westwood, 1993).

4. Quantity: One sample requires 50–100 leaves from 5–10 trees of the same variety.

5. Preparation: Place leaves immediately in a paper bag (not plastic — leaves may suffocate and spoil). Send them to the laboratory on the day of collection or the next day, after air‑drying at room temperature.

Interpretation of results:

Nutrient concentrations in pear leaves are compared with reference values (Jackson, 2003; Mitcham, 2007). We provide main ranges for pear leaves in July–August (in % and ppm of dry matter):

For manganese, the toxicity level is given for the bark of one‑year‑old shoots (Jackson, 2003).

Note: Norms may vary slightly depending on variety, region, analytical method, and tree age. Therefore, rely on the recommendations of the laboratory performing the analysis.

Advantages and limitations:

• Leaf analysis gives accurate information on the current nutritional status.
• However, it does not reveal the cause of a deficiency. For example, low zinc content may be due either to its soil deficiency or to high pH (alkaline reaction) that binds zinc. Therefore, leaf analysis should be combined with soil analysis (Agustí, 2010).

Visual Signs of Deficiency and Excess

An observant gardener can notice many problems from the appearance of leaves, shoots, and fruits. However, visual diagnosis requires experience, as symptoms of different deficiencies can be similar and sometimes mask each other.

What to look for:

1. Nitrogen (N).

• Deficiency: Leaves are pale green, yellowing starting from lower (older) leaves. Shoots are thin, weak, short. Tree grows slowly. Fruits are small, pale (Agustí, 2010).
• Excess: Leaves are dark green, large, shoots are excessively long and vigorous (“luxuriant growth”). Tree enters bearing late. Fruits are large but store poorly and are prone to diseases. Wood maturation is delayed, reducing winter hardiness (Jackson, 2003).

2. Phosphorus (P).

• Deficiency: Rarely seen. Leaves become dark green, sometimes with a purple or bronze tint on the underside. Shoot growth slows. Flowering and fruit ripening are delayed (Westwood, 1993).

3. Potassium (K).

• Deficiency: Edges of older leaves turn brown, “scorched”. Leaves may curl. Fruits become smaller, lose colour, become less sweet (Agustí, 2010).
• Excess: May exacerbate magnesium and calcium deficiencies by competing with them for root uptake (Jackson, 2003).

4. Calcium (Ca).

• Deficiency: Young leaves become deformed, edges curl upward. Shoot tips may die back. Fruits show “bitter pit” and other physiological disorders. Calcium is the most “unsatisfied” element; its deficiency is especially critical for fruit quality (Agustí, 2010; Jackson, 2003).

5. Magnesium (Mg).

• Deficiency: Yellow or reddish spots appear between veins of older leaves (“marbling”). Tissue at leaf margins and around veins may die. Lower leaves are affected first (Agustí, 2010).

6. Iron (Fe).

• Deficiency (chlorosis): Young leaves yellow or whiten between veins. Veins remain green. Occurs on carbonate soils and with over‑watering. Pears on quince rootstocks are more sensitive to chlorosis (Jackson, 2003).

7. Zinc (Zn).

• Deficiency (“rosetting”): Young leaves become small, narrow, chlorotic, clustered in a rosette at the shoot tip (“little leaf”). Internodes shorten. This is a very characteristic symptom for pear (Westwood, 1993).

8. Boron (B).

• Deficiency: Young leaves yellow, thicken, become brittle. Shoots die back (“tip dieback”). Flowers wilt, fruits are small, deformed, with corky spots, may crack (Agustí, 2010).
• Excess: Leaves become brown at margins and drop prematurely. Fruits lose storage life. Boron is toxic even at slight over‑application (Jackson, 2003).

9. Manganese (Mn).

• Deficiency: Pale‑yellow spots between veins on young leaves (unlike iron, veins are not always green). Often occurs simultaneously with zinc deficiency (Agustí, 2010).

Visual diagnosis is the first step. Always verify your assumptions with leaf and soil analyses, especially if you plan to apply significant amounts of mineral fertilisers.

Integrated Approach: From Observation to Action

The ideal diagnostic scheme for the home gardener:

1. Annually in spring — observe tree condition (leaf colour, growth, flowering).

2. Every 2–3 years — soil analysis to monitor pH and major element levels.

3. Annually in late July — leaf analysis for precise adjustment of autumn and spring fertilisation.

4. When suspicious symptoms appear — additional leaf analysis (or specific elements) for urgent correction.

This approach will allow you not to waste money on unnecessary fertilisers and not to harm the tree, but to ensure it has everything it needs for stable cropping.

In the next chapter, we will consider which fertilisers are best for pear, in what forms, and how to combine them correctly.

Types of Organic Fertilisers

Specifics of Organic Fertilisers for Pear

1. Pear, like other pome fruits, responds well to organics. Mulching the root‑zone circles with compost or rotted manure is one of the best practices for maintaining fertility (Westwood, 1993).

2. Optimal carbon‑to‑nitrogen ratio (C:N). For rapid decomposition and effective nutrition, it is better that the organic material has a C:N within 20:1 – 30:1 (Table 2). Manure has a C:N of about 5–20:1 (very rich in nitrogen), straw — 80:1 (low in nitrogen, may cause nitrogen starvation during decomposition). Compost usually has a balanced ratio.

| Material | C:N |

|----------|-----|

| Rotted cattle manure | ~20:1 |

| Poultry manure | ~5:1 |

| Wheat/rye straw | ~75:1 |

| Compost | 15–25:1 |

Source: Hochmuth and Sideman, 2023.

3. Organics are not only nutrition. Their main role for pear is to create comfortable conditions for roots: aeration, moisture retention, biological activity. Pear roots are sensitive to soil compaction, and regular organic applications are the best way to keep soil loose (Westwood, 1993).

4. Application rates. For a mature bearing pear tree, it is desirable to apply 30–50 kg of well‑rotted manure or compost once every 2–3 years. For young trees — 15–20 kg. This provides both nutrition and soil improvement.

Advantages and Disadvantages of Organic Fertilisers

Practical Advice

If you have the opportunity, use organics in combination with mineral fertilisers. Organics are the foundation of long‑term fertility, while mineral fertilisers allow precise correction of nutrition at key growth stages. For example, apply compost and humus in autumn, and add small doses of nitrogen and potassium fertilisers in spring for a quick start.

Remember: Organic fertilisers work best on soils with pH 6.5–7.5. On acidic soils, their effectiveness decreases due to low microbial activity. So first bring pH to normal (liming), then actively apply organics.

In the next chapter, we will discuss mineral fertilisers — how to choose the right form, calculate doses, and avoid common mistakes.

Nitrogen Fertilisers

Nitrogen is the most frequently applied element, but also the most “tricky”. Its excess leads to vegetative overgrowth, reduced winter hardiness, and poorer fruit quality. Therefore, nitrogen applications must be strictly dosed and timed to specific growth phases.

Main forms of nitrogen fertilisers:

Compiled from: Hochmuth and Sideman, 2023; Westwood, 1993.

When and how much nitrogen to apply for pear:

• Young trees (pre‑bearing): Total nitrogen requirement is about 30–50 g of active ingredient (a.i.) per tree per year. Apply in spring (before flowering) and early summer (during active shoot growth). No nitrogen in autumn to avoid delaying wood maturation.
• Bearing trees: Approximate rate — 50–100 g a.i. per tree per year (in terms of nitrogen removed with the crop, about 0.5–1.0 g per 1 kg of fruit). More accurately, the rate is calculated based on leaf analysis results. Apply in spring (before flowering) and after flowering (at fruit set). Nitrogen is not applied in autumn unless soil reserves need replenishment (Jackson, 2003).

Important rule: Nitrogen fertilisers are best applied in splits — 2–3 applications during the spring‑summer period, rather than one large dose. This reduces leaching risk and ensures uniform nutrition.

Choosing nitrogen form:

• On soils with pH below 5.5, calcium nitrate is preferred (it does not acidify).
• On neutral and alkaline soils, urea or ammonium nitrate can be used (Mandal et al., 2021).
• Urea is good for foliar feeding (0.3–0.5% solution) — it penetrates leaves quickly.

Phosphorus Fertilisers

Phosphorus is immobile in soil, especially on acid and alkaline soils. Its availability strongly depends on pH: the optimal range is 6.5–7.5. Therefore, phosphorus fertilisers are best applied locally — into the active root zone (Hochmuth and Sideman, 2023).

Main phosphorus fertiliser forms:

Compiled from: Hochmuth and Sideman, 2023; Westwood, 1993.

When and how much phosphorus to apply:

• At planting: Definitely add 200–400 g of single superphosphate (or 100–150 g of double) to the planting hole, mixed with topsoil. This supplies roots with phosphorus for 3–5 years.
• For bearing trees: Apply 30–60 g P₂O₅ per tree annually (autumn or spring). Phosphorus is usually applied as part of compound fertilisers or separately as superphosphate under digging (Westwood, 1993).

Tip: Phosphorus fertilisers should be incorporated into the soil to a depth of 15–20 cm (into the main absorbing root zone). Surface application is ineffective because phosphorus hardly moves down the soil profile (Agustí, 2010).

Potassium Fertilisers

Potassium is one of the most demanded elements for pear, especially during fruit fill. It increases sugar content, improves colour, and storage life. Potassium is quite soluble, but on loamy and clay soils it may become fixed (bound) in unavailable forms, so on such soils potassium rates are increased (Westwood, 1993).

Main potassium fertiliser forms:

Compiled from: Hochmuth and Sideman, 2023; Westwood, 1993.

When and how much potassium to apply:

• Young trees: 30–50 g K₂O per tree per year, best in spring.
• Bearing trees: 80–150 g K₂O per tree per year (depending on yield). Apply in splits: part in spring (before flowering), part in early summer (during fruit set and growth), and part in autumn (after harvest to build reserves).
• For pear, potassium sulfate is preferable, as potassium chloride in large doses can inhibit roots (Westwood, 1993). If potassium chloride is used, apply it in autumn so that chloride is leached from the root zone.

Interaction with other elements: High soil potassium content can reduce magnesium and calcium uptake. Therefore, at high potassium rates, monitor magnesium and calcium levels in leaves and apply them additionally if necessary (Jackson, 2003).

Compound Mineral Fertilisers

Compound fertilisers contain two or three major elements (NPK) in various ratios. They are convenient because you do not need to mix separate components. However, it is important to choose the right formula for the specific growth phase.

Common grades (NPK) and their use:

Specialised fruit tree fertilisers: Many manufacturers produce fertilisers labelled “For fruit crops” (e.g., “Fertika”, “Aquarin”). Their composition is usually balanced for apple and pear needs.

How to use: The package always has instructions with dosages. For pear, split application (2–3 times per season) according to growth phases is recommended: spring — nitrogen/compound, summer — potassium‑phosphorus, autumn — phosphorus‑potassium (no nitrogen).

Micronutrients in Mineral Fertilisers

Many compound fertilisers already contain micronutrients (zinc, manganese, boron, copper, iron) in chelated form — the most available to plants. This is convenient, as separate micronutrient applications are not required.

However, in cases of acute deficiency (e.g., rosetting due to zinc shortage), it is better to use separate micronutrient fertilisers as foliar sprays (see Chapter 6).

Main micronutrient fertilisers:

Compiled from: Hochmuth and Sideman, 2023; Westwood, 1993.

Practical Recommendations for Using Mineral Fertilisers for Pear

1. Always rely on analyses (soil, leaves). Excess mineral fertilisers is more dangerous than deficiency.

2. Split application is the key rule. Especially for nitrogen (2–3 applications) and potassium (2 applications).

3. Apply fertilisers in the active root zone (root‑zone area to a depth of 15–20 cm). Surface spreading is ineffective for phosphorus and potassium (Westwood, 1993).

4. Consider weather. In dry weather, fertilisers are best applied with irrigation (fertigation — see Chapter 6). In rainy weather, they can be spread dry.

5. Apply micronutrients as needed (based on analyses or visual signs). Excess boron and zinc are toxic (Jackson, 2003).

Example mineral fertilisation schedule for a mature bearing pear (per tree):

• Spring (before bud break): 30–50 g ammonium nitrate or urea (depending on analyses) + 30 g potassium sulfate.
• After flowering (fruit set phase): 30–50 g compound fertiliser (e.g., 10–10–10) or 20–30 g potassium sulfate + 20–30 g superphosphate (if phosphorus is needed).
• Summer (fruit fill period): 40–60 g potassium sulfate (can be with a small amount of nitrogen if growth support is needed).
• Autumn (after harvest): 50–80 g superphosphate + 30–50 g potassium sulfate (no nitrogen) under digging.

In the next chapter, we will look at how to distribute these applications over the seasons — “Seasonal Feeding”.

Spring Feeding

Spring is the time of root awakening and the start of active shoot, leaf, and flower growth. During this period, the tree mainly uses nitrogen and other elements stored from autumn in roots and wood (Jackson, 2003). However, these reserves are not always sufficient, especially after a cold winter or in young orchards. Therefore, it is important to support the tree with available nitrogen and potassium.

Purpose of spring feeding: to stimulate leaf, shoot, and flower growth, ensuring good pollination and fruit set.

When to apply: Early spring — immediately after snow melt and sap flow begins (before bud break). A second application at the “green cone” stage or at the start of flowering.

Which elements to apply: The main element is nitrogen, to a lesser extent potassium. Phosphorus is less needed in spring, but it is best applied in advance (autumn).

Recommended rates (per mature tree):

1. Before bud break: Apply 30–50 g ammonium nitrate or 20–30 g urea (if leaf analysis shows nitrogen is normal or low). Nitrogen fertiliser should be incorporated into the soil to a depth of 5–10 cm within the canopy projection. If the soil is moist, it can be spread on the surface and lightly raked (Westwood, 1993).

2. If the tree is weak or growing on sandy soil: add 20–30 g potassium sulfate (potassium improves nitrogen uptake and strengthens tissues).

3. For young trees (up to 5 years): reduce nitrogen rates by half (20–30 g per tree) to avoid excessive shoot growth.

Important: Spring nitrogen applications should not be made on soils with high nitrogen content (by analysis) or if leaf analysis shows excess nitrogen (>2.6%). Excess nitrogen in spring can provoke vegetative overgrowth at the expense of flowering and flower bud set (Agustí, 2010).

Feeding After Flowering

After flowering, fruit set and initial fruit growth occur, along with active formation of young leaves and shoots. At this time, the tree especially needs potassium and, to a lesser extent, nitrogen. Potassium affects fruit size, taste, colour, and disease resistance (Agustí, 2010).

Purpose of post‑flowering feeding: to improve fruit set, stimulate fruit growth, and promote flower bud initiation for the next year.

When to apply: Immediately after flowering, when ovaries reach pea size (the “young ovary” phase).

Which elements to apply: Potassium (potassium sulfate) combined with a small amount of nitrogen (if needed) and micronutrients, especially boron (to improve fertilisation and reduce ovary drop) and zinc (for normal tissue development) (Westwood, 1993).

Recommended rates (per mature tree):

• Potassium sulfate: 30–50 g (or 40–60 g of K‑Mag if magnesium is deficient).
• Nitrogen (if necessary): no more than 20–30 g ammonium nitrate (if leaf analysis shows nitrogen deficiency).
• Boron (foliar): spraying with 0.05–0.1% boric acid solution or boron‑containing products during full bloom or immediately after. Boron is very important for pear: its deficiency leads to poor fruit set and fruit deformation (Jackson, 2003).
• Zinc (foliar): if rosetting symptoms appear or by analysis — 0.1–0.2% zinc sulfate (ZnSO₄) solution with a surfactant. Best combined with boron.

Summer Feeding

Summer is the main period of fruit growth and nutrient accumulation. Pear actively consumes potassium and nitrogen, but nitrogen rates should be moderate so as not to delay ripening and reduce fruit storage life (Jackson, 2003). At the end of summer, flower bud initiation for the next year’s crop begins — a very important stage.

Purpose of summer feeding: to supply the tree with potassium and available nitrogen for maximum fruit growth and quality, as well as for flower bud formation.

When to apply: During active fruit growth (late June – July) and early August. Timing depends on region and variety (earlier for summer varieties, later for winter ones).

Which elements to apply: Mainly potassium, moderate amounts of nitrogen (no more than 20–30 g per tree). Phosphorus is usually not needed in summer feeding (applied in autumn).

Recommended rates (per mature tree):

• Potassium feeding: 40–60 g potassium sulfate or 50–70 g K‑Mag in mid‑July.
• If signs of nitrogen deficiency (pale leaves, weak growth): add 20–30 g urea (or ammonium nitrate) in early July.
• Foliar micronutrient feeding: In hot weather (above 25°C), foliar spraying with chelated micronutrients (zinc, manganese, boron) is beneficial. This helps avoid heat stress and improves nutrition (Mandal et al., 2021).

Important: In late summer (August), nitrogen applications should cease, so as not to stimulate shoot growth before winter. The last nitrogen feeding should be no later than mid‑July (Westwood, 1993).

Autumn Feeding

Autumn is the time for preparing the tree for winter and storing nutrients in roots and wood. The main elements that should be in abundance are phosphorus and potassium. Nitrogen is not applied in autumn, as it stimulates growth and hinders tissue maturation, reducing frost hardiness (Jackson, 2003).

Purpose of autumn feeding: to accumulate phosphorus and potassium in the tree’s organs for better overwintering and early spring growth, as well as to improve soil fertility.

When to apply: After harvest, in September–October (before frost). In southern regions — October–November.

Which elements to apply: Mainly phosphorus and potassium. Organic fertilisers are also preferably applied in autumn.

Recommended rates (per mature tree):

• Superphosphate (single or double): 50–80 g (or 20–30 g double superphosphate) worked into the root‑zone soil. Phosphorus is immobile, so it is best incorporated to 15–20 cm depth (Agustí, 2010).
• Potassium sulfate: 30–50 g (can be combined with phosphorus or use K‑Mag if magnesium is needed).
• Organic fertilisers: 20–30 kg of rotted manure or compost per tree (or 3–5 kg per 1 m² of root‑zone area). Organics in autumn decompose slowly and become available to roots by spring. They also improve soil structure (Westwood, 1993).

Important: In autumn, apply phosphorus‑potassium fertilisers mixed with organic matter (compost) to reduce contact with roots and prevent burning.

General Feeding Schedule for Pear (Mature Bearing Tree)

Note: Rates are adjusted for a mature tree (over 10 years) with a crop removal of about 30–50 kg. For young trees, rates are reduced by 1.5–2 times (Westwood, 1993). Always adjust rates based on leaf and soil analysis results.

Special Considerations for Young Trees

• Up to 3–4 years: Main focus is nitrogen and phosphorus for crown and root system formation. Potassium applied in moderate amounts.
• Nitrogen: 20–30 g per tree in spring (June) and after flowering. No nitrogen in autumn.
• Phosphorus and potassium: 20–30 g superphosphate and 20–30 g potassium sulfate in autumn under digging.
• Organics: 10–15 kg compost per tree every 2 years (autumn).

What to Avoid

1. Nitrogen fertilisation after August — reduces winter hardiness and causes shoot freeze‑damage.

2. Surface application without incorporation — many elements (especially phosphorus, potassium) do not penetrate the soil and remain unavailable to roots.

3. Applying urea and ammonium nitrate on alkaline soils — they enhance alkaline reaction, reducing micronutrient availability (Jackson, 2003).

In the next chapter, we will discuss application methods — “Methods of Application”: soil application, fertigation, and foliar feeding, their advantages and rules.

Soil Application: Classic Approach and Rules

This is the most common method in amateur orchards. Fertilisers are incorporated into the soil in the zone of the main absorbing roots. However, the effectiveness of this method strongly depends on incorporation depth, fertiliser form, and soil moisture.

Basic rules for soil application for pear:

1. Incorporation depth. The bulk of active pear roots are at 20–40 cm depth (Westwood, 1993). Therefore, fertilisers should preferably be incorporated into this layer. Surface broadcasting without incorporation is ineffective for phosphorus (immobile) and potassium (fixed in surface layers on heavy soils) (Agustí, 2010).

• Nitrogen fertilisers (nitrate forms) are mobile and can move deeper with irrigation or rain. But on light soils, they leach easily, so they are best applied in splits and shallow (5–10 cm).
• Phosphorus and potassium fertilisers require incorporation to 15–20 cm (into the root zone). They can be applied in furrows or holes around the canopy perimeter (root zone) (Westwood, 1993).

2. Incorporation methods:

• Broadcasting with subsequent digging (or cultivation) to 10–15 cm depth — suitable for organic fertilisers and nitrogen (except phosphorus). Be careful not to damage roots: dig the root‑zone area only with a fork or cultivator, no deeper than 15 cm.
• Application in furrows or pits. A more effective method for phosphorus and potassium. Along the canopy perimeter, make grooves (furrows) 20–25 cm deep or pits (6–8 per circle), apply fertiliser, mix with soil, and cover. This ensures local placement of elements in the active root zone.
• Local application (in root‑zone wells). Using a special auger, make wells 30–40 cm deep under the canopy projection (8–10 wells per tree), fill with fertilisers (especially phosphorus and potassium), mixing with soil (Westwood, 1993). Labour‑intensive but very effective for immobile elements.

3. Timing of soil application. Most mineral fertilisers are best applied in spring (before flowering) or autumn (after leaf fall). Organics — in autumn, so they partly decompose by spring. Nitrogen fertilisers are applied in spring (split), phosphorus‑potassium — in autumn (usually all at once) (Jackson, 2003).

4. Soil moisture. Applying fertilisers to dry soil is ineffective and may cause root burn. After fertiliser application, water the tree (if no rain) to dissolve salts and move them to the roots. This is especially important for nitrogen fertilisers, which can be lost as gases (ammonia) when broadcast without incorporation in dry weather (Hochmuth and Sideman, 2023).

When soil application is preferable:

• At orchard establishment (planting holes or trenches with organics and phosphorus).
• For baseline (background) doses of phosphorus and potassium.
• For organic fertilisers.
• In orchards without irrigation systems (fertigation not possible).

Fertigation: Precision and Economy

Fertigation is the application of fertilisers through drip or sprinkler irrigation systems. This method is especially effective in intensive orchards with drip irrigation. It allows nutrients to be supplied precisely to the root zone and in small doses, significantly increasing fertiliser use efficiency and reducing losses (Hochmuth and Sideman, 2023).

Advantages of fertigation for pear:

• High precision. Fertilisers are delivered directly to roots, bypassing intermediate soil losses.
• Fertiliser savings. Total doses can be reduced by 20–30% compared to traditional application (Klein and Weinbaum, 2000).
• Split application. The ability to perform “drip” feedings in small doses every 1–2 weeks, ideally matching the tree’s seasonal needs.
• Quick response. Roots receive nutrients immediately after application, allowing rapid correction of deficiencies.
• Automation. Easily automated.

Specifics of fertigation for pear:

1. Only for highly soluble fertilisers. Use fully water‑soluble forms: nitrates (calcium nitrate, potassium nitrate), urea, monopotassium phosphate, compound fertilisers (fertigation grades). Phosphorus is best applied as orthophosphoric acid or monopotassium phosphate, as other phosphorus fertilisers may precipitate.

2. Solution concentration. Do not exceed electrolyte concentration in irrigation water to avoid root burn. Typically recommended concentration is 0.5–1.0 g/L (i.e., no more than 1 kg fertiliser per 1000 L water). For sensitive crops (young saplings), even lower (Hochmuth and Sideman, 2023).

3. Fertiliser composition must be balanced. With fertigation, it is easy to create imbalance if only nitrogen or only potassium is applied. Therefore, use special compound fertilisers with micronutrients (e.g., 20‑20‑20 + micro, or formulas with high potassium in summer).

4. Timing: Fertigation is carried out during active growth (spring to mid‑summer). In late summer and autumn, fertigation is stopped (or only phosphorus‑potassium blends without nitrogen are used).

5. Drip irrigation system. Fertigation is most effective with drip irrigation, as water is delivered directly to the root zone and fertilisers are not spread over inter‑rows (Klein and Weinbaum, 2000).

Example fertigation schedule for pear:

Disadvantages of fertigation:

• Requires a drip irrigation system and a fertiliser injector.
• High equipment cost and maintenance expenses.
• Incorrect settings may clog emitters (especially with phosphate fertilisers and hard water).
• Uneven fertiliser distribution with uneven irrigation.

Who benefits: Fertigation is ideal for intensive orchards with drip irrigation. In amateur gardens, it is rarely used due to complexity, but where drip irrigation exists, it is a very effective method.

Foliar Feeding (Leaf Sprays)

Foliar feeding is the spraying of leaves with fertiliser solutions. Leaves can absorb many elements (especially micronutrients, urea nitrogen, potassium, and phosphorus in some forms) and direct them into plant tissues (Swietlik and Faust, 1984). This method does not replace basic soil nutrition, but is an excellent supplement, especially for correction of micronutrient deficiencies and emergency intervention.

Advantages of foliar feeding:

1. Rapid action. Fertilisers enter leaf tissues directly and are incorporated into metabolism within hours.

2. Effective when root problems exist. If roots are damaged by frost, diseases, or soil compaction, foliar feeding is the only way to deliver nutrients quickly.

3. Precise targeting. Nutrients can be directed to specific elements at specific stages (e.g., boron and zinc during flowering).

4. Small doses. Micronutrients are used in minimal amounts, reducing toxicity risk.

5. Compatibility with pesticide treatments. Fertilisers can often be added to tank mixes with insecticides or fungicides (saving time) (Swietlik and Faust, 1984).

Limitations:

• Elements with low mobility (calcium) move poorly in phloem, so foliar application rarely reaches fruit. Calcium must be applied to soil or directly to fruit (not leaves) (Jackson, 2003).
• Macronutrients (nitrogen, potassium, phosphorus) are inefficient to apply in large amounts via leaves — they are needed in large volumes, and leaves may be burned.
• Weather dependence. In hot sunny weather, the solution dries quickly and leaves salt burns. Optimal spraying is early morning or evening, in cloudy but not rainy weather (Westwood, 1993).
• Form selection. Not all fertilisers are suitable for foliar application. Chelated forms of micronutrients (they penetrate cuticle faster) and highly soluble salts (urea, potassium sulfate, magnesium sulfate, zinc and manganese sulfates) are preferred. Potassium chloride is not used for foliar feeding because chloride can burn leaves.

For pear, foliar feeding is especially recommended for:

• Zinc — best way to correct rosetting (0.1–0.2% ZnSO₄ solution at leaf unfolding or after flowering).
• Boron — to improve fruit set (0.05–0.1% boric acid before and after flowering).
• Manganese — for chlorosis on alkaline soils (0.1–0.2% MnSO₄).
• Urea — for quick nitrogen supply in spring (0.5% solution) or in autumn after harvest (5% solution for nitrogen storage in tissues before winter) (Swietlik and Faust, 1984).
• Potassium and phosphorus — as monopotassium phosphate (0.3–0.5%) during fruit fill to improve taste and colour.

Rules for foliar feeding:

1. Concentration — do not exceed recommended. For most salts — 0.1–0.3%, for urea — 0.5–1.0% (depending on stage and purpose). Exceeding causes leaf burn (Westwood, 1993).

2. Add a surfactant (e.g., soap or specialised adjuvant) — improves leaf wetting and solution retention.

3. Spray thoroughly, but so solution does not run off — droplets should stay on leaves.

4. When combining with pesticides, check compatibility according to instructions.

5. Foliar feeding is effective in early growth (young leaves absorb better) and under stress (drought, temperature fluctuations).

Comparison of Application Methods: Which to Choose for Pear

Practical Recommendations for the Home Gardener

1. Main method — soil application. It should always be the foundation. Apply organics in autumn, phosphorus and potassium under digging, nitrogen in spring in splits (with incorporation or in furrows).

2. Use foliar feeding as “first aid”. When signs of deficiency appear (rosetting, chlorosis, poor fruit set), conduct 1–2 sprays with appropriate products. This gives a quick effect.

3. If you have drip irrigation — master fertigation. This will significantly increase fertiliser efficiency and produce higher quality fruit. Start with simple water‑soluble fertilisers and micro‑doses.

4. Monitor results. After any application method (especially foliar and fertigation), observe the tree’s response — improvement should be seen within 7–10 days. If not, the cause may be other factors (watering, diseases, soil compaction).

In the final chapter, we will discuss common mistakes in pear fertilisation: what not to do and how to correct the consequences of improper feeding.

Mistake 1: Excessive Nitrogen Nutrition (Over‑feeding with Nitrogen)

Symptoms: Tree grows vigorously, shoots are long (over 50–60 cm per season), leaves large, dark green, but fruiting is poor or absent. Fruits, if any, are large but watery, store poorly, and are disease‑prone. Wood does not mature, winter hardiness decreases, and the tree may freeze even in mild winters (Jackson, 2003; Westwood, 1993).

Cause: Applying too high rates of nitrogen fertilisers (especially ammonium nitrate or urea) at the expense of other elements. Often happens when gardeners “feel sorry” for the tree and give a lot of nitrogen “for growth”.

How to fix:

• Stop nitrogen applications for the current season (and possibly the next, if the tree is too “luxuriant”).
• Restore balance — apply increased doses of potassium and phosphorus (they promote wood maturation and reduce the negative effect of excess nitrogen).
• Adjust irrigation: with excess nitrogen, reduce watering (if it was frequent) to slow growth.
• Perform summer pruning (pinching) of overly long shoots to stop their growth and redirect resources to maturation.
• For the future: strictly dose nitrogen based on leaf analysis results. Normal nitrogen concentration in pear leaves is 1.8–2.6% (Jackson, 2003). If analysis shows above 2.6%, do not apply nitrogen next season.

Important: Excess nitrogen on alkaline soils (pH > 7.5) is especially dangerous because it exacerbates micronutrient deficiencies (zinc, iron, manganese), which are already poorly available under such conditions (Agustí, 2010).

Mistake 2: Unbalanced Fertiliser Application (Element Imbalance)

Symptoms: A typical example — high potassium and low calcium/magnesium. This leads to bitter pit in fruit, poor storage, cracking. Or conversely, excess phosphorus on acid soils causes zinc and iron deficiencies (Westwood, 1993; Jackson, 2003).

Cause: Gardeners often apply individual elements without considering their antagonism (mutual suppression). For example, excess potassium competes with calcium and magnesium for root uptake. Excess phosphorus binds zinc and iron in the soil.

How to fix:

• Use compound fertilisers (NPK + micronutrients) instead of individual elements — they are already balanced.
• Monitor the N : K : Ca ratio in leaves. For pear, optimal: K/Ca < 1.5 (by fruit content) (Agustí, 2010). If potassium is too high — reduce its rate and apply calcium (e.g., calcium nitrate or gypsum).
• Regularly check soil pH. At pH 6.5–7.5, most elements are available in optimal proportion. At deviations — correct pH (liming for acid, gypsum or organics for alkaline).
• Apply micronutrients in chelated form — they do not compete with each other and are better absorbed.

Mistake 3: Incorrect Timing of Fertiliser Application

Symptoms: Nitrogen applied late (August–September) causes late shoot growth, which does not mature and freezes in winter. Phosphorus and potassium applied in spring on the surface do not reach the root zone and are ineffective. Fresh organics applied in spring can cause nitrogen starvation (nitrogen immobilisation by microorganisms) (Westwood, 1993).

Cause: Misunderstanding of the tree’s developmental phases and their nutritional needs.

How to fix and do correctly:

• Nitrogen: only up to mid‑July (in temperate zones) or end of July (in the south). The last nitrogen feeding is immediately after flowering. In autumn and late summer — no nitrogen.
• Phosphorus and potassium: best applied in autumn (under digging) or early spring (in furrows). They move slowly in soil, so deep incorporation is needed (Hochmuth and Sideman, 2023).
• Organics: apply in autumn (rotted) or spring, but only well‑rotted (compost, humus). Fresh manure — only in autumn (3–4 months before planting).
• Foliar feeds: strictly by phenological phases. Boron — before and immediately after flowering. Zinc — in spring when leaves open. Urea — before flowering or in autumn after leaf fall (Swietlik and Faust, 1984).

Mistake 4: Ignoring Micronutrients, Especially Zinc and Boron

Symptoms: Rosetting of leaves (small, narrow leaves) — zinc deficiency. Poor fruit set, fruit deformation, shoot dieback — boron deficiency. Chlorosis of young leaves (veins green, tissue yellow) — iron deficiency. These symptoms are often mistaken for diseases or drought consequences (Jackson, 2003).

Cause: Most gardeners focus on macronutrients, forgetting about micronutrients. On alkaline soils, micronutrients are often unavailable even if present in soil.

How to fix:

• Conduct diagnostics (leaf analysis). If zinc is below 16 ppm, boron below 15 ppm — apply urgently (Mitcham, 2007).
• Foliar feeding is the most effective method. For zinc — 0.1–0.2% ZnSO₄ in spring. For boron — 0.05–0.1% boric acid before and after flowering. For iron — Fe chelates (Fe‑EDDHA) on carbonate soils (Jackson, 2003).
• Apply micronutrients in chelated form in soil or with irrigation (fertigation) on sandy soils.
• Improve soil pH — on alkaline soils (pH > 7.5), micronutrients are bound. Adding organics and sulfur helps acidify soil.

Mistake 5: Surface Fertiliser Application Without Incorporation

Symptoms: Fertilisers lie on the surface and do not reach the roots. Especially for phosphorus and potassium, which are immobile. The tree suffers deficiency despite adequate applied amounts.

Cause: Many gardeners simply scatter fertilisers around the trunk (as on a lawn) and leave them. On dry soil or without incorporation, phosphorus and potassium do not move downwards, while nitrogen (especially ammoniacal) may volatilise (Hochmuth and Sideman, 2023).

How to fix:

• Always incorporate fertilisers into the soil (to 5–15 cm depth) — by digging, cultivation, or raking.
• For phosphorus and potassium, make furrows or pits around the canopy perimeter and place fertiliser there (depth 15–20 cm) (Westwood, 1993).
• If digging is not possible — after broadcasting, water generously (this helps nitrogen but not phosphorus or potassium). For phosphorus and potassium, incorporation is mandatory.

Mistake 6: Applying Fresh Organic Fertilisers Without Composting

Symptoms: In the first year after applying fresh manure or straw, the tree may yellow and slow growth — this is “nitrogen starvation” (microorganisms decomposing organics immobilise available nitrogen). Moreover, fresh manure contains weed seeds and pathogens (Hochmuth and Sideman, 2023).

Cause: Desire to save time and use what is at hand.

How to fix: The rule is one — use only rotted organics (compost, humus, well‑aged manure, at least 6–12 months old). If you have already applied fresh manure, additionally apply a small dose of nitrogen fertiliser (20–30 g ammonium nitrate per tree) to compensate for immobilisation.

Mistake 7: Neglecting Soil Type and pH

Symptoms: On acidic soils (pH < 5.5), calcium, magnesium, molybdenum are often deficient, and phosphorus is bound in unavailable forms. On alkaline soils (pH > 7.5), iron, zinc, manganese, and boron are deficient (Jackson, 2003). Gardeners often do not know their soil pH and apply fertilisers blindly, leading to imbalance.

How to fix:

• Conduct a pH test (portable pH meter or litmus paper). Optimal range for pear is 6.5–7.5 (Mandal et al., 2021).
• At pH < 6.0 — liming (application of dolomite, lime) in autumn. Rate — 2–3 kg per 10 m² (depending on acidity) (Westwood, 1993).
• At pH > 8.0 — acidification (application of sulfur, ammonium sulfate, iron chelates). For chlorosis control, iron chelates (Fe‑EDDHA) are especially effective as foliar or soil application (Jackson, 2003).

Mistake 8: Ignoring Autumn Feeding

Symptoms: Tree wakes up slowly in spring, blooms weakly, leaves small. This indicates a shortage of stored nutrients that should have been accumulated in autumn.

Cause: Many gardeners forget about the tree after harvest, thinking it is already resting. In reality, autumn is when flower buds for the next year are initiated and reserves are stored (Jackson, 2003).

How to fix:

• Always apply phosphorus and potassium in autumn (after leaf fall but before frost). Phosphorus improves root formation, potassium increases winter hardiness.
• Apply organics (compost, humus) in autumn — they will decompose by spring.
• Do not apply nitrogen in autumn — it will stimulate growth and reduce winter hardiness.

Mistake 9: Single Large‑Dose Application Instead of Split Dosing

Symptoms: After a single large dose of nitrogen (e.g., 100 g ammonium nitrate at once), the tree may suffer root burn, leaves become dark green and brittle. Some nitrogen leaches before being absorbed (Agustí, 2010).

Cause: Desire to do everything quickly and “for a long time”.

How to fix: Split the annual nitrogen (and other elements) rate into 2–3 applications. For example: 30% — before flowering, 30% — after flowering, 40% — in early summer (if needed). This ensures continuous nutrition and reduces losses.

Mistake 10: Using Low‑Quality or Inappropriate Fertilisers

Symptoms: No response to feeding, leaf burns, soil contamination with ballast substances (chlorine, sodium, heavy metals). Often occurs with cheap mixtures or industrial wastes.

Cause: Saving on quality.

How to fix:

• Use fertilisers from reputable manufacturers with full composition and guarantees.
• For pear, chloride‑free potassium forms (potassium sulfate, K‑Mag) are preferred over potassium chloride.
• For foliar — chelated forms of micronutrients (safer and more effective than salts).
• Avoid fertilisers with high chloride content — they inhibit roots and reduce fruit quality (Westwood, 1993).

How to Avoid Mistakes: Gardener’s Checklist

1. Conduct analyses (soil — every 2–3 years, leaves — annually in July). This is your main guide.

2. Do not apply fertilisers “by eye” — use scales and measuring utensils.

3. Remember: better under‑feed than over‑feed. Excess macronutrients (especially nitrogen and potassium) is more dangerous than moderate deficiency.

4. Consider developmental phases: spring — nitrogen, summer — potassium, autumn — phosphorus and potassium (no nitrogen).

5. Use organics and minerals together. Organics are the basis of long‑term fertility, minerals for quick correction.

6. Monitor soil pH — without optimal pH even the best fertilisers will not be absorbed.

7. Observe the tree — its appearance is the best indicator. When deficiency symptoms appear (chlorosis, rosetting, small fruit), adjust feeding promptly.

8. Don’t forget micronutrients — they are critical for pear, especially zinc and boron.

Good luck and generous harvests! If you follow these recommendations, your pear will reward you with delicious, healthy fruit and a long life.