Seedling Method

Best Option – Individual Containers without Subsequent Picking

For eggplant, it is optimal to grow seedlings directly in individual pots, cups, or peat pellets, so as to avoid transplanting with root damage (picking). The plant develops in a permanent container until transplanting into the ground, and the root system remains undamaged.

Which containers are suitable?

• Peat pots and pellets. An excellent option, especially for beginners. The plant can be planted directly in the pot – it decomposes in the soil, and the roots are not injured. Choose pots with a diameter of at least 8–10 cm so that the roots have enough space (Kasynkina & Kudin, 2018). Peat pellets are best used for initial germination and then transferred to a larger container.
• Plastic cups (0.5–1 L). A reliable and affordable option. Be sure to make drainage holes in the bottom to avoid water stagnation. It is convenient to use transparent cups – this way you can monitor root development.
• Seedling cassettes with large cells. Cells with a volume of at least 0.3–0.5 L are suitable for eggplant, but plants can only grow in them up to a certain size. If using cassettes, choose cells with a depth of at least 10 cm.
• Plastic containers or boxes (for sowing with subsequent picking). This option is acceptable if you are ready to pick at an early stage (in the cotyledon phase) and do it very carefully. However, remember that this is additional stress for the plant. If you still choose a common box, ensure a depth of at least 10–12 cm and do not thicken the sowing.

What to avoid:

• Containers that are too small (less than 0.2 L). In them, the root system will quickly fill the entire volume, and growth will slow down.
• Containers without drainage holes – excess moisture leads to root rot.
• Containers made of impermeable materials that do not allow roots to "breathe".

If You Still Plan to Pick

If you chose sowing in a common box, picking should be done as early as possible – in the cotyledon or first true leaf phase (Autko et al., 2012; Panteleev, 1986). At this age, the seedling does not yet have a highly branched root system, and damage is minimal. When picking, bury the plant up to the cotyledon leaves, gently press the roots with soil, and water lightly.

However, keep in mind that even early picking delays the development of seedlings by 10–14 days compared to growing without it (Autko et al., 2012). Therefore, if possible, it is better to plant immediately in individual containers.

Soil Requirements

Eggplants are demanding of the soil: they need loose, nutritious, moisture‑retentive but well‑drained soil with a neutral or slightly acidic reaction. Optimal pH is 6.0–6.5 (Autko et al., 2012; Tarakanov & Mukhin, 2003). In acidic or too alkaline soil, plants poorly absorb nutrients, suffer from chlorosis and root rots.

The soil should:

• Easily allow air and moisture to pass through.
• Retain moisture but not become waterlogged.
• Contain sufficient organic matter and major nutrients (nitrogen, phosphorus, potassium).
• Be free from pathogenic microorganisms, pests, and weed seeds.

Recipe for a Universal Soil Mix

Here is a proven soil recipe for eggplant seedlings, which is suitable for most regions and conditions (Tarakanov & Mukhin, 2003; Autko et al., 2012; Torikov & Sychev, 2018):

Ratio:

• Garden or field soil (sod soil) – 2 parts.
• Humus or well‑rotted compost – 1 part.
• Perlite or coarse sand – 1 part.

For a bucket (about 10 L) of this mixture, it is useful to add:

• Wood ash – 1 cup (source of potassium and micronutrients).
• Superphosphate – 1–2 tablespoons (source of phosphorus, important for root growth).
• Complex mineral fertilizer (nitroammophoska or similar) – 1–2 tablespoons.

Alternative Recipes for Different Conditions

• For peat‑based soils. If you use high‑moor peat (acidic), add dolomite flour or lime at the rate of 15–20 g per 1 kg of peat to neutralise acidity (Torikov & Sychev, 2018). Also add perlite (20–30% by volume) and humus (20–30%).
• Soilless option. Mix: 70% peat + 30% perlite or sand + fertilizers. Such soil is light, sterile, but requires more frequent watering and feeding.
• For those with little time. You can use a purchased specialised soil for nightshades (tomatoes, peppers, eggplants). Pay attention to the composition – it should be loose, with a pH around 6.0.

Soil Disinfection

This is a crucial step that is often overlooked. Soil may contain pathogens (especially root rots, fusarium, phytophthora) and pest eggs. To avoid problems, the soil must be disinfected. Here are three reliable methods:

1. Baking (pasteurisation). Spread the soil on a baking sheet in a layer no more than 5–7 cm and heat in the oven at 100–120 °C for 30–40 minutes (Autko et al., 2012). This will destroy most pathogens. After cooling, it is useful to enrich the soil with beneficial microflora (for example, water it with a solution of Fitosporin or Trichodermin).

2. Steaming. Pour boiling water over the soil, cover with a lid and leave for 8–12 hours. Then drain excess water and allow the soil to cool.

3. Chemical disinfection. Water the soil with a 1% solution of potassium permanganate or a solution of Fitosporin according to instructions. However, remember that chemicals can kill not only harmful but also beneficial microorganisms, so after treatment let the soil "breathe" for 1–2 days.

Important: disinfection is needed not only for purchased soil but also for your own soil. Even garden soil can be infected.

Moistening the Soil Before Sowing

A day before sowing, thoroughly moisten the soil with warm water so that it is damp but not wet (a clump compresses in the hand, but water does not drip). The soil should settle a little. This will ensure good seed‑to‑soil contact and speed up germination.

Drainage

At the bottom of each container, be sure to place a drainage layer 1–2 cm thick (expanded clay, pebbles, crushed brick, coarse sand). This will prevent water stagnation, which is extremely dangerous for eggplant roots.

Disinfection (Dressing)

This is a mandatory step, as many pathogens (especially bacterial spots, fusarium, phytophthora) can be transmitted through seeds (Tarakanov & Mukhin, 2003). There are several available disinfection methods:

1. Heat treatment (heating). Seeds are placed in hot water at a temperature of 48–50 °C for 20–30 minutes, then quickly cooled in cold water and dried to a free‑flowing state (Autko et al., 2012). This method is effective against many fungal and bacterial diseases. It is important to precisely observe the temperature and time: if overheated, seeds may lose germination.

2. Treatment in a potassium permanganate solution. Seeds are soaked in a 1% solution of potassium permanganate (5 g per 0.5 L of water) for 30 minutes (Autko et al., 2012). After treatment, they are thoroughly washed in clean water. This is a simpler and more accessible method, but it is less effective against bacterial infections than heat treatment.

3. Treatment in a hydrochloric acid solution (for large batches). Seeds are kept in a 20% hydrochloric acid solution for 30 minutes. This method requires care and the use of protective gloves; it is mainly used in seed‑growing farms (Autko et al., 2012).

4. Fungicide treatment. To protect against root rots and fusarium, you can use specialised fungicides (for example, preparations based on benomyl, thiram) according to instructions. This is especially relevant for seeds collected from plants that were diseased in the previous season.

Stimulation of Germination

To accelerate germination, seeds can be soaked in one of the following solutions:

• In clean warm water. Seeds are soaked for 12–16 hours in water at room temperature (about 20–25 °C), changing the water every 6–8 hours. This is the simplest and safest method (Autko et al., 2012).

• In aloe juice. Aloe has biostimulating properties. Seeds are soaked in undiluted aloe juice for 12 hours. The juice is first kept in the refrigerator for 2–3 days to activate beneficial substances (Autko et al., 2012).

• In a solution of growth stimulants. Use preparations such as Epin‑Extra, Zircon, or Potassium Humate according to instructions. They increase germination energy and plant resistance to stress.

• In a solution of micronutrients. You can use complex micronutrient fertilisers with boron, manganese, copper, molybdenum, zinc (Autko et al., 2012). For example, dissolve 0.2–0.5 g of boric acid, manganese sulphate, copper sulphate, and zinc sulphate in 1 L of water. Soaking is carried out for 12–24 hours.

Bubbling (for experienced gardeners)

Bubbling is the treatment of seeds in water with the supply of oxygen or air. To do this, seeds are placed in a container with water at room temperature, at the bottom of which an aquarium compressor is placed. Air supply is carried out for 18–24 hours (Autko et al., 2012). This method significantly accelerates germination and increases the uniformity of shoots, especially for slow‑germinating eggplant seeds. After bubbling, the seeds are slightly dried to a free‑flowing state and sown.

Germination (Vernalisation)

The most reliable way to speed up emergence is pre‑germination of seeds. Seeds are spread between layers of wet gauze, cloth, or filter paper and placed in a warm place with a temperature of 25–27 °C (Autko et al., 2012). It is important to keep the cloth constantly moist, but not to flood the seeds with water – they must breathe. As a rule, after 3–5 days, small roots appear (chitting). As soon as 5–10% of seeds have sprouted, they are sown in the soil. Do not delay – sprouts may overgrow and be damaged during sowing.

Sowing Dates

We have already discussed the calculation of dates in the previous chapter. Let us recall the key formula:

Transplanting date – (60–75 days for seedlings + 5–7 days for emergence) = sowing date.

Sowing Depth

Sowing depth is one of the most important factors for uniform and friendly emergence. Eggplant is sown at a depth of 0.5–1 cm (Autko et al., 2012; Kasynkina & Kudin, 2018). If sown too deeply, the seeds will not have enough strength to break through to the surface; seedlings will be weak and sparse. If sown too shallowly, the seeds may dry out or become exposed during watering.

Practical advice: if sowing in a common box, make shallow grooves about 1 cm deep with row spacing of 3–4 cm. Place the seeds at a distance of 0.5–1 cm from each other. Then carefully cover them with sifted soil or sand with a layer of about 0.5–1 cm and lightly press down.

If sowing directly into individual cups, make a 1 cm depression in the centre of each, place a seed, and cover with soil.

Seeding Rate

For eggplant, the seeding rate in the seedling method is 0.8–1.5 kg/ha in agricultural scales (Panteleev, 1986). For small volumes, this means: in a common box – about 2–3 g of seeds per 1 m² of sowing surface; when sowing in cassettes or cups – 1 seed per container. If you use old or low‑germination seeds, you can put 2 seeds in one container, and then, after emergence, remove the weaker plant by pinching it off at the soil surface so as not to damage the roots of the neighbour.

Sowing Technique

1. Soil preparation. A day before sowing, water the soil with warm water. It should be moist but not wet.

2. Make depressions (grooves). To a depth of 0.5–1 cm.

3. Place the seeds. At a distance of 0.5–1 cm from each other (in common boxes) or one in the centre of each cup.

4. Cover with soil. The soil layer should be no more than 1 cm.

5. Lightly press down. Press the soil with your palm or a small object to ensure good seed‑to‑soil contact.

6. Moisten the surface. Spray with warm water from a sprayer. Do not allow the soil to wash away.

7. Cover the containers. To create a greenhouse effect (high humidity and stable temperature), cover the containers with glass, transparent film, or a lid. This will speed up germination.

Conditions for Germination

After sowing, create ideal conditions for the seeds:

• Temperature: 25–27 °C – optimal for uniform emergence (Autko et al., 2012). At lower temperatures (18–20 °C), seedlings will appear 5–7 days later and will be less uniform.
• Humidity: Keep the soil moist but not waterlogged. Ideally, soil moisture should be at 70–80% of full water‑holding capacity (Autko et al., 2012).
• Light: Before emergence, light is not required, but as soon as the first shoots appear, the containers should be immediately moved to the brightest place.

When Seedlings Emerge

At optimal temperature (25–27 °C), the first shoots appear on the 5–7th day. At lower temperatures (18–20 °C) – on the 10–14th day (Kasynkina & Kudin, 2018). As soon as the first "loops" appear – white curved stems – immediately remove the film or glass to avoid overheating and stretching, and move the containers to a well‑lit place.

How Often to Water?

Watering is one of the most common causes of problems with eggplant seedlings. Both overwatering and underwatering are equally dangerous.

• Before picking (or before the appearance of 2–3 true leaves): water moderately, maintaining soil moisture at 70–80% of full water‑holding capacity (Autko et al., 2012). The soil should be moist but not wet. Excess moisture leads to root rot and the development of fungal diseases.
• After picking (if carried out): in the first 2–3 days, reduce watering to allow plants to adapt, then return to the normal regime.
• In hot, sunny weather: water more often – about once every 2–3 days.
• In cloudy, cool weather: reduce watering to once every 4–5 days.

Watering Rules

• Water temperature: use only warm water (23–24 °C) (Autko et al., 2012). Cold water causes stress, slows growth, and can provoke root rot.
• Time of watering: it is better to water in the morning so that the leaves dry out by evening, which prevents fungal diseases.
• Watering method: water at the root, without pouring on leaves and stems. Use a watering can with a fine spout or a syringe without a needle for spot watering. Water should not get on the root collar – this can provoke damping‑off.
• Sign of proper watering: the soil is soaked with moisture to the full depth of the root layer, but water does not stagnate in the tray. If water stagnates – be sure to drain it 20–30 minutes after watering.

Signs of Watering Problems

1. Prepare the Containers

Prepare individual pots or cups with a volume of 0.3–0.5 L (optimally 0.5 L) in advance. Be sure to make drainage holes in the bottom. Fill them with the same soil in which the seedlings grew (to avoid stress from changing soil). The soil should be moist but not wet. Make a depression in the centre of each pot with a finger or a peg, 3–4 cm deep.

2. Prepare the Seedlings

2–3 hours before picking, water the seedlings abundantly with warm water. This will make the roots more elastic and reduce injury when extracting them. Wet soil easily shakes off the roots.

3. Extract the Seedlings

Carefully lift the seedling with a small stick, spoon, or a special picking peg. Try to hold the plant by the cotyledon leaves or by the clump of soil around the roots, but not by the stem – it is very fragile and easily damaged. Extract the plant together with a small clump of soil.

4. Inspect the Roots

Remove damaged or rotten roots. If the root is too long, you can slightly pinch (shorten) the taproot by 1/3 of its length – this stimulates the development of lateral roots (Panteleev, 1986). However, for eggplant this operation is not necessary – many agronomists advise not to touch the root to avoid unnecessary stress (Autko et al., 2012; Torikov & Sychev, 2018).

5. Plant the Seedling

Place the seedling into the prepared hole in the new pot so that the roots are spread out and not bent upward. Bury the plant up to the cotyledon leaves – this promotes the formation of additional roots on the buried part of the stem. The cotyledon leaves should not touch the ground to avoid rotting.

6. Cover with Soil

Cover the roots with soil, gently pressing it with your fingers. The soil should fit tightly around the roots – do not leave voids. The root collar (the transition point from stem to root) should be at the soil surface level or slightly buried (but not deeper than the cotyledons).

7. Water

Water abundantly the transplanted plant with warm water (23–24 °C) at the root. This will compact the soil around the roots and improve root‑soil contact. Water should not get on the cotyledons and stem.

8. Create Shade

For the first 1–2 days after picking, shade the plants from direct sunlight (for example, with paper or light cloth). This will reduce moisture evaporation through the leaves and help the plants adapt faster. After 2–3 days, remove the shade.

Sowing in Cassettes Followed by Transplanting

Instead of classical picking with root pinching, you can use the transplanting method – moving the plant from a smaller container to a larger one together with a clump of soil, without disturbing the root ball. This method is much less traumatic. Transplanting is carried out when the roots have completely entwined the soil clump (usually at the age of 30–40 days), moving the plant to a pot 1–2 sizes larger.

Peat Pellets

Another way to avoid picking is sowing in peat pellets. They are swollen in water, then a seed is placed in the centre. When roots appear, the pellet together with the plant is transferred to a pot with soil. The roots are not injured.

Sowing in Individual Containers from the Start

As already mentioned, this is the best option. Simply sow 1–2 seeds in a 0.5 L cup, and the plants will develop there until transplanting. With this method, picking is not needed.

First Feeding: 10–14 Days After Picking (or in the Phase of 2–3 True Leaves)

If you grow seedlings without picking, the first feeding is carried out in the phase of 2–3 true leaves (approximately 20–25 days after emergence).

Purpose: to stimulate root system growth and above‑ground part development.

Composition (per 10 L of water):

• Ammonium nitrate – 10–12 g
• Double superphosphate – 8–10 g
• Potassium salt (or potassium sulphate) – 6–8 g (Autko et al., 2012)

Or use a complex fertiliser (nitroammophoska, azophoska) – 15–20 g per 10 L of water.

Method: root watering at the root. Consumption – 0.1–0.2 L per plant (or 3–5 L per 1 m² of sowing area).

Second Feeding: 12–14 Days After the First

Purpose: to ensure active growth of vegetative mass before flower bud initiation.

Composition (per 10 L of water):

• Ammonium nitrate – 15–18 g
• Double superphosphate – 10–12 g
• Potassium salt – 8–10 g (Autko et al., 2012)

Method: root watering. Consumption – 0.2–0.3 L per plant.

Third Feeding: 10–14 Days Before Transplanting

Purpose: to prepare plants for transplant stress, stimulate flower bud initiation, and increase resistance.

Composition (per 10 L of water):

• Ammonium nitrate – 8–10 g (reduce nitrogen share)
• Superphosphate – 15–20 g (increase phosphorus for roots and flowering)
• Potassium salt – 12–15 g (potassium increases stress tolerance) (Tarakanov & Mukhin, 2003)

Method: root watering. Consumption – 0.2–0.3 L per plant.

Foliar Feedings (on Leaves)

In addition to root feedings, foliar feedings with micronutrients are very effective. They act quickly, especially in case of deficiencies of iron, boron, manganese, zinc.

The first foliar feeding is carried out 7–10 days after picking (Autko et al., 2012). Subsequent – at intervals of 10–14 days.

Composition of the stock solution of micronutrients (per 10 L of water): (Autko et al., 2012)

• Boric acid – 5 g (dissolve in a small amount of hot water)
• Zinc sulphate – 3 g
• Iron sulphate (chelated) – 15 g
• Ammonium molybdate – 3 g
• Cobalt sulphate – 3 g
• Copper sulphate – 3 g
• Manganese sulphate – 5 g

For the working solution: add 0.25 L of the stock solution and 2–3 drops of iodine to 10 L of water to enhance the effect (Autko et al., 2012).

Consumption of the working solution – 0.1 L per 1 m² of sowing area (or until the leaves are completely wet). Spraying is carried out in the morning or evening hours to avoid sunburn.

Important: do not mix foliar feedings with fungicides or insecticides unless specified in the instructions.

Organic Feedings

For those who prefer organic farming, you can use:

• Cow manure infusion (1:10) – infuse for 3–5 days, then dilute with water 1:5 and water at the root. However, this is less precise in composition than mineral fertilisers, and may be a source of pathogens if the manure is of poor quality.
• Nettle infusion (1:5) – a good source of nitrogen and potassium.
• Potassium or sodium humate – a growth stimulant that improves nutrient uptake (Torikov & Sychev, 2018). Use according to instructions.

Ready‑Made Complex Fertilisers for Seedlings

Specialised stores sell ready‑made compositions, for example:

• "Kemira‑Lux" (for seedlings and flowers).
• "Agricola" (for nightshades).
• "Effecton".
• "Rastvorin" (complete water‑soluble fertiliser).

Use them strictly according to the package instructions; usually the concentration is 0.5–1% (5–10 g per 10 L of water).

Day 1–2: Exposure to Sun

On the first day, take the seedlings out to a glazed balcony, veranda, or greenhouse for 1–2 hours in the morning or evening, when the sun is not the strongest (Autko et al., 2012). Protect the plants from direct sunlight with light cloth, gauze, or paper, especially if they have never seen direct sun.

On the second day, increase the outdoor time to 3–4 hours, gradually removing shading in the morning hours.

Important: if the outside temperature is below +12 °C or there is a strong wind, postpone hardening or carry it out in a wind‑protected place (for example, on a glazed loggia).

Day 3–7: Increasing Time and Exposure

• Increase the time spent outdoors by 1–2 hours daily.
• By the end of the first week, the seedlings should spend the entire daylight hours (8–10 hours) outdoors (Tarakanov & Mukhin, 2003).
• Gradually remove shading – first in the morning hours (before 11:00), then in the afternoon. However, on very hot days (above +28 °C), still shade the plants from scorching rays to avoid burns.
• If nights are already warm (above +12 °C), you can leave the seedlings on the balcony overnight (Panteleev, 1986).

Day 8–10: Pre‑Transplant Hardening

• 3–4 days before transplanting, the seedlings should be round‑the‑clock outdoors or in a greenhouse with open vents (if weather permits). The night temperature should not drop below +8…+10 °C – this is the minimum threshold for eggplant without damage (Kotov & Adritskaya, 2016).
• In the last 2 days before transplanting, reduce watering so that the plants wilt slightly – this slows growth and increases cell sap concentration, which increases cold resistance (Torikov & Sychev, 2018). However, do not allow severe wilting!
• A day before transplanting, water the seedlings abundantly – this will facilitate extraction from pots and reduce transplant stress (Tarakanov & Mukhin, 2003).

For Transplanting into Open Ground

Hardening should be as complete as possible. The seedlings must get used to fluctuations in day and night temperatures, wind, and direct sunlight. Ideally, 3–5 days before transplanting, nights should be warm (not below +12 °C) so that the plants can be left outdoors round the clock.

Important: if frosts are forecast, bring the seedlings indoors at night and return them outside in the morning.

For Transplanting into a Greenhouse (Film, Polycarbonate)

Hardening can be less intensive. It is enough to start ventilating the greenhouse during the day 7–10 days in advance, opening vents or doors. 3–4 days before transplanting, leave the greenhouse open all day and close it at night (if the temperature drops below +10 °C). Hardened seedlings adapt faster to the greenhouse microclimate.

For Regions with Short Summers and Cool Climates

Hardening is especially important, as transplanting occurs in unstable weather. However, in northern regions, night temperatures often remain low until summer. In this case:

• Take the seedlings outside only on warm days.
• Be sure to bring them indoors at night.
• Use temporary covers (film, spunbond) to protect from night cold.
• The hardening period can be extended to 14 days to allow plants to adapt to unstable conditions.

Symptoms

• Stems are thin, long, pale.
• Internodes are greatly elongated (more than 5–7 cm).
• Leaves are small, light green or yellowish.
• Plants lean toward the light source.

Causes

• Insufficient light – the most common cause. Especially in February–March, when the day is short and the sun is low (Autko et al., 2012).
• Too high temperature with insufficient light. In warmth, plants actively grow upward, but due to light deficit they cannot develop normally.
• Dense sowing – seedlings compete for light and stretch.
• Excess nitrogen fertiliser – stimulates stem growth at the expense of roots and leaves.

Solution

1. Immediately improve lighting. Move seedlings to the brightest windowsill. Use supplementary lighting with phytolamps or fluorescent lamps (up to 12–14 hours per day). In the first days after emergence, round‑the‑clock supplementary lighting for 3–5 days is recommended (Autko et al., 2012).

2. Lower the temperature. Daytime to 18–20 °C, nighttime to 16–17 °C in the first days after emergence. Lower temperature inhibits stretching (Torikov & Sychev, 2018).

3. Carry out picking or transplanting into a larger container. If plants are crowded, they start stretching. Transplant them into individual containers, burying to the cotyledon leaves.

4. Remove excess seedlings. If sowing was dense, thin out the seedlings.

5. Adjust feeding. Reduce nitrogen share, increase phosphorus and potassium (Tarakanov & Mukhin, 2003).

6. In especially neglected cases, you can pinch the top above the 3–4th true leaf – this will stop upward growth and stimulate lateral shoot development, but delays flowering by 7–10 days.

Symptoms

• Leaves become pale, yellow (chlorosis). Often starts with lower leaves and gradually moves upward.
• Green veins on a yellow background (interveinal chlorosis) may be observed.
• Growth slows down.

Causes

• Nitrogen deficiency (N) – leaves become pale green, lower leaves yellow, growth slows.
• Iron deficiency (Fe) – chlorosis of young leaves: veins green, tissue between them yellow. Often occurs at alkaline soil pH (>7.0) (Rubatzky & Yamaguchi, 1997).
• Magnesium deficiency (Mg) – chlorosis of lower leaves between veins.
• Waterlogging – roots suffocate, nutrient uptake is disrupted.
• Low temperature – roots do not absorb elements, especially phosphorus. At soil temperatures below 16 °C, phosphorus uptake drops by 50–75% (Autko et al., 2012).

Solution

1. Diagnose. Determine which elements are lacking (see signs in chapter 7).

2. Nitrogen starvation: apply ammonium nitrate (5–7 g per 10 L of water) or diluted cow manure infusion (1:10).

3. Iron chlorosis: apply foliar feeding with iron chelate (according to instructions) or spray with 0.5% ferrous sulphate solution. Also check soil pH – at pH above 7.0, iron becomes unavailable. Add peat to the soil or acidify the water for watering (a few drops of citric acid per 1 L of water).

4. Magnesium chlorosis: apply magnesium sulphate (10 g per 10 L of water) by watering or foliar.

5. Waterlogging: reduce watering, dry the soil, improve drainage. If roots have started to rot – transplant into fresh soil, cutting off damaged roots.

6. Low temperature: raise the temperature to optimal values (20–23 °C daytime, 17–18 °C nighttime). Use warm water for watering (not below 22 °C).

Symptoms

• The root collar darkens, becomes thin, as if constricted (hence the name).
• The lower part of the stem turns black and softens.
• The plant leans and falls, wilts.
• Often a white or grey coating is observed on the soil surface.

Causes

• Fungal disease caused by soil pathogens (Rhizoctonia, Pythium, Phytophthora) (Tarakanov & Mukhin, 2003).
• Excessive soil and air moisture.
• Dense sowing.
• Poor ventilation.
• Use of non‑disinfected soil.
• Sharp temperature fluctuations contribute to infection.

Solution

At the initial stage:

1. Immediately remove diseased plants (they cannot be saved).

2. Sprinkle the soil surface around healthy plants with dry calcined sand, vermiculite, or crushed charcoal in a layer of 0.5–1 cm. This will absorb excess moisture and create a barrier for the fungus (Autko et al., 2012).

3. Reduce watering to a minimum, water only when the top soil layer dries.

4. Treat healthy plants with biological preparations: Fitosporin‑M, Trichodermin, Bactofit according to instructions. You can use a weak potassium permanganate solution (pale pink) for watering.

5. Improve ventilation – regularly air the room, but avoid draughts.

If the disease has progressed far:

• Transplant healthy plants into fresh disinfected soil with added sand or vermiculite. Rinse the roots in a weak potassium permanganate solution. Water minimally after transplanting, for 3–5 days.

Prevention (the most reliable means):

• Use only disinfected soil (steamed or calcined).
• Do not thicken sowing.
• Water moderately, only with warm water.
• Ventilate regularly.
• Add 10–15% sand or vermiculite to the soil during sowing to improve aeration (Torikov & Sychev, 2018).

Symptoms

• Various spots on leaves: brown, yellow, with or without a border.
• Spots may be dry or wet, with or without coating.

Possible Causes and Solutions

Aphids

• Symptoms: clusters of small insects (green, black) on shoot tips and underside of leaves. Leaves become deformed, curled, covered with sticky honeydew.
• Solution: wash plants with soapy water (1 tbsp liquid soap per 1 L of water). In severe cases – treat with biological preparations (Fitoverm, Aktofit, according to instructions) or insecticides (Aktara, Iskra).

Spider Mites

• Symptoms: small white dots on leaves (punctures), then thin webs on the underside of leaves and between stems. Especially dangerous in dry and warm air (Rubatzky & Yamaguchi, 1997).
• Solution: increase air humidity – spray plants and the air around with water, wash leaves. In severe cases – treat with acaricides (Actellik, Fitoverm).

Thrips

• Symptoms: small silvery or white stripes on leaves, dots (excrement), leaf deformation (Autko et al., 2012).
• Solution: treatment with insecticides (Aktara, Confidor) according to instructions.

Whitefly

• Symptoms: small white moths that fly up when touched; eggs and larvae can be seen on the underside of leaves. Sticky coating on leaves.
• Solution: treatment with preparations (Aktara, Fitoverm). In greenhouses, biological enemies (Encarsia) are used (Kotov & Adritskaya, 2016).

Important: when treating with insecticides, observe the waiting period – 7–10 days before transplanting, chemical preparations should not be used (Torikov & Sychev, 2018). Use biological preparations or folk remedies (infusions of garlic, tobacco, nettle) for prevention.

Symptoms

• The plant does not grow upward.
• Leaves acquire a dark green, bluish, or purple tint (especially on the underside).
• The stem becomes stiff, "woody".

Cause

• Phosphorus deficiency (P) or cold soil. At soil temperatures below 14–16 °C, eggplant roots lose the ability to absorb phosphorus by 50–75%, and even if phosphorus is present in the soil, it becomes unavailable (Autko et al., 2012; Rubatzky & Yamaguchi, 1997).

Solution

1. Raise the soil temperature to 20–22 °C. Use warm water for watering (23–24 °C).

2. Carry out foliar feeding with phosphorus – spray leaves with a solution of monopotassium phosphate (5 g per 10 L of water) or superphosphate extract (steep 10 g of superphosphate in 1 L of hot water, then dilute to 10 L).

3. If the temperature is normal but phosphorus is lacking, carry out root feeding with superphosphate (10 g per 10 L of water).

Symptoms

• Leaves curl upward, downward, or into a "boat".
• The leaf blade becomes wrinkled, corrugated.
• Young leaves grow ugly, uneven.

Causes and Solutions

• Calcium deficiency (Ca): young leaves are deformed, apical buds die. Solution: feed with calcium nitrate (5 g per 10 L of water) at the root or on leaves (Rubatzky & Yamaguchi, 1997).
• Boron deficiency (B): apical bud dies, leaves thicken, become brittle. Solution: foliar feeding with boric acid (1 g per 1 L of water) (Autko et al., 2012).
• Temperature fluctuations or draughts – leaves may temporarily curl but then unfold. Eliminate draughts, stabilise temperature.
• Herbicide toxicity (if herbicides were used on seedlings or nearby). Symptoms: leaves become "fern‑like", severely deformed. Unfortunately, such a plant will most likely die.

Sign

• Roots visible in drainage holes.
• The root ball is dense, does not crumble when removed from the pot.

Solution

The plant has outgrown its pot and needs transplanting into a larger container (0.3–0.5 L larger) (Tarakanov & Mukhin, 2003). If less than 7–10 days remain before transplanting, you can skip this and simply increase watering and feeding. If there is plenty of time – transplant, without disturbing the root ball.

Treatment Against Diseases and Pests

Even if the seedlings look healthy, it is useful to carry out a preventive treatment before transplanting (Autko et al., 2012; Tarakanov & Mukhin, 2003):

• Spraying with 1% Bordeaux mixture or copper‑based preparations (HOM, Oxychom) – protection against fungal diseases (phytophthora, alternaria). Treatment is carried out 2–3 days before transplanting.
• Treatment with biological preparations (Fitosporin, Trichodermin, Alirin‑B) – an environmentally friendly option for preventing root and leaf infections.
• Inspection for pests. If aphids, thrips, or spider mites are found – treat with biological preparations (Fitoverm, Aktofit) or insecticides according to instructions. 7–10 days before transplanting, chemical preparations should not be used (Torikov & Sychev, 2018).

Stimulation of Root Formation

For better survival, a day before transplanting, you can water the seedlings with a root formation stimulant solution:

• Kornevin – 1 g per 1 L of water, watering at the root.
• Heteroauxin – according to instructions.
• Potassium humate – stimulates root formation and increases stress resistance.

Hardening Off (Final Stage)

If you started hardening 10–14 days in advance, then 3–4 days before transplanting, the seedlings should be outdoors round the clock (if nights are warm – above +12 °C). If nights are cold – bring them indoors at night and take them out again in the morning.

On the day of transplanting, do not water the seedlings, so that the soil clod is moist but not wet – this way it crumbles less during transplanting (Panteleev, 1986).

Site Requirements

Eggplant is the most heat‑loving crop among nightshades (Rubatzky & Yamaguchi, 1997). Choose for it:

• The warmest, sunniest spot in the garden, protected from cold winds. Ideally – a southern slope.
• Soil: light, well‑drained, fertile sandy loam or loamy soils with pH 6.0–6.5 (Autko et al., 2012). Heavy clay and acidic soils are unsuitable.
• Predecessors: the best are legumes, onions, cucumbers, cabbage. Do not plant eggplants after tomatoes, peppers, potatoes, and other nightshades – this increases the risk of diseases (especially phytophthora and fusarium) (Tarakanov & Mukhin, 2003).
• Transplanting dates: only when the threat of return frosts has passed, and the average daily air temperature is established at 18–20 °C, and the soil has warmed up to 15–18 °C at a depth of 10–15 cm (Kasynkina & Kudin, 2018).

Bed Preparation

1–2 weeks before transplanting, prepare the soil:

1. Dig the area to a depth of 25–30 cm.

2. Apply fertilisers per 1 m²:

• Humus or compost – 5–8 kg.
• Superphosphate – 30–40 g.
• Potassium salt – 15–20 g.
• Ammonium nitrate – 15–20 g (can be applied partially, leaving some for top dressing) (Autko et al., 2012; Torikov & Sychev, 2018).
• Form ridges 15–20 cm high for better warming and drainage.
• Water the ridges with warm water a day before planting.

If the soil is acidic, 2–3 weeks before planting, apply dolomite flour or lime (200–300 g per 1 m²) to normalise pH (Tarakanov & Mukhin, 2003).

Timing and Weather

• Transplant on a cloudy day or in the afternoon when the sun is not active. This reduces stress and prevents burns.
• If the day is sunny and hot, shade the seedlings for 3–5 days (e.g., with non‑woven material, newspapers, or shields).

Planting Scheme

The optimal scheme for eggplant (Autko et al., 2012; Panteleev, 1986):

• Between rows: 60–70 cm (for short varieties) or 70–90 cm (for tall varieties).
• Between plants in a row: 30–40 cm (for medium‑sized) or 40–50 cm (for vigorous).
• Density: 2.5–4 plants per 1 m² (depending on variety and region). Crowding leads to reduced yield and diseases.

Planting Technique

1. Make holes 15–20 cm deep according to the chosen scheme.

2. Water each hole with warm water (0.5–1 L per plant).

3. Carefully remove the plant from the pot, trying not to destroy the soil clod. If the roots have entwined the clod – the plant is ready for transplanting. If roots protrude from drainage holes – that is normal.

4. Place the plant in the hole. Bury up to the first true leaves (but not deeper!) – this stimulates the formation of additional roots (Tarakanov & Mukhin, 2003). For overgrown seedlings – bury up to 2–3 true leaves or plant "lying" in a furrow at a 45° angle.

5. Cover the roots with soil, compact to avoid voids.

6. Water again with warm water (0.3–0.5 L per plant) for better root‑soil contact.

Protection Against Return Frosts

If cooling (below +10 °C) or return frosts are forecast, immediately after transplanting install covers:

• Arches and film or spunbond – the most reliable method.
• Cut plastic bottles (over each plant) – a temporary solution.
• Cardboard boxes or newspapers – overnight.

Remove covers when the threat of frost has completely passed and daytime temperatures are steadily above 20 °C (Torikov & Sychev, 2018).

Watering

• In the first week after transplanting, water the seedlings daily (or every other day) with warm water at the root, but in small doses (0.3–0.5 L per plant) to avoid washing away roots.
• Later – as the top soil layer dries (usually 1–2 times a week). In hot weather, increase watering to 2–3 times a week.

Shading

In the first 3–5 days, protect plants from direct sunlight (especially at midday), especially if hot weather sets in after planting. Use spunbond, newspapers, branches, or special shade nets.

Loosening

After each watering or rain, as soon as the soil dries slightly, carefully loosen between rows to a depth of 5–8 cm, so as not to damage the roots. This improves aeration and destroys weeds.

First Feeding

10–14 days after transplanting, when the plants have established and started growing, carry out the first feeding:

• Nitrogen fertilisers (20 g ammonium nitrate per 10 L of water) – for active growth of vegetative mass (Autko et al., 2012).
• Or complex fertiliser (15–20 g nitroammophoska per 10 L of water).

Consumption – 0.5–1 L per plant.

Advice: if the plants start growing immediately after transplanting, the first feeding can be done earlier (on day 5–7). If plants have stopped growing – postpone until full recovery.

Variety Selection

For direct sowing in the ground, choose only early‑maturing and cold‑tolerant varieties of eggplant with a short growing season (80–100 days). For example: "Almaz", "Galine", "Balagur", "Robin Hood", "Karlik", etc. (Kasynkina & Kudin, 2018). Late‑maturing varieties (140–160 days) will not ripen even in the south in a seedless culture.

Sowing Dates

Sowing is carried out when the soil warms up to 18–20 °C at a depth of 10 cm. In southern regions, this usually happens in late April – early May, in more northern regions – in late May – early June (Kasynkina & Kudin, 2018; Panteleev, 1986).

Important: do not rush! If sown too early, seeds may rot in cold, waterlogged soil. And if frosts (even light down to -1 °C) strike after emergence, the plants will die. Eggplant is the most cold‑sensitive crop among nightshades (Rubatzky & Yamaguchi, 1997).

Soil Preparation and Sowing

1. Dig the area to a depth of 25–30 cm, remove weeds.

2. Apply humus (5–8 kg/m²), superphosphate (30–40 g/m²), and potassium salt (15–20 g/m²).

3. Form high ridges (15–20 cm) for better warming and drainage.

4. Water the soil with warm water a day before sowing.

Sowing:

• Scheme: as for seedling planting – 60–70 cm between rows, 30–40 cm in the row.
• Sowing depth: 1–2 cm (shallower on heavy soils, slightly deeper on light soils) (Tarakanov & Mukhin, 2003).
• Seeding rate: 2–3 seeds per hole (in case of poor germination), then after emergence leave the strongest plant, pinch the rest at the ground (do not pull out to avoid damaging roots of neighbours).

Cover for Early Shoots

To accelerate germination and protect against possible cold snaps, you can use temporary covers (Autko et al., 2012):

• Film on arcs – creates a greenhouse effect, accelerates emergence by 5–7 days.
• Cut plastic bottles or jars – cover each hole until emergence, protecting from cold and wind.
• Spunbond – covers the entire bed, protecting from frost and creating a favourable microclimate.

Remove covers when the threat of frost has passed and the plants have strengthened (2–3 true leaves appear).