Plant diagnostics

1.1. General Assessment of the Leaf Rosette

Start by stepping back and assessing the planting as a whole. Pay attention to the color and overall condition of the tops.

• Color: Bright, rich green is a sign of health. Yellowing, paleness, reddening, or the appearance of spots are reasons for a more detailed inspection (Nonnecke, 1989).
• Habit (growth form): Plants should look vigorous, with a rosette raised above the ground. Drooping, prostrate leaves, or conversely, curled and deformed leaves, are stress signals.
• Uniformity: Assess whether the problem is widespread or isolated to individual plants. If all plants have yellowed, the cause is likely in the soil or weather. If only one bush is deformed, it could be a virus or localized damage (Kemble, 2022).

1.2. Examination of Central, Young Leaves

This is the most important step, immediately setting the direction for diagnosis. Move to the very heart of the plant—the growing point from which new leaves emerge.

• Purpose: Check for deformation, curling, necrosis (dieback) of the growing point, or newly formed leaves. Here, we look for signs of deficiencies in elements such as boron (B) and calcium (Ca), as well as viral infections.
• Logic: Young, actively growing tissues are "hostages" to immobile elements. Boron and calcium cannot be moved from old leaves to new ones. If they are lacking in the soil, the growing point is the first to suffer. At the same time, many viruses also prefer to attack young, actively dividing cells (Goldman, 2020; Rana, 2018).

Key Principle: If the problem starts with young leaves, your search circle narrows sharply to deficiencies of immobile elements (boron, calcium), viruses, or herbicide stress.

1.3. Examination of Old, Outer Leaves

After checking the "nursery," move to the lowest, oldest leaves of the rosette. These are the first to suffer from a lack of mobile elements and from natural aging.

• Purpose: Determine the nature of wilting or dieback of the old foliage. Do they wilt evenly, or are there distinct spots? Does chlorosis (yellowing) appear between the veins or along the edges?
• Logic: Nitrogen (N), potassium (K), and magnesium (Mg) are "mobile" elements. When deficient, the plant begins to "cannibalize" old leaves, translocating nutrients from them to young shoots. Therefore, characteristic symptoms (e.g., vein yellowing in magnesium deficiency or edge yellowing in potassium deficiency) manifest on the old tops (Nonnecke, 1989; Wien & Stützel, 2020).

Key Principle: If the problem starts with old leaves, it is almost always starvation for mobile elements (nitrogen, potassium, magnesium), or natural aging.

1.4. Examination of Petioles and the Root Neck

Examine the leaf petioles—they can tell you a lot about the plant's condition.

• Purpose: Check for longitudinal cracks, spots, or damage.
• Logic: Longitudinal cracks on petioles are a classic symptom of boron deficiency (Rana, 2018). Darkening, almost "glassy" spots may indicate bacterial infections penetrating the vascular system. You can also notice signs of pest activity here, such as leaf miners (Kemble, 2022).

1.5. Examination of the Top of the Root Crop (Crown)

Sometimes the first signs of a problem are visible precisely at the transition point from stem to root.

• Purpose: Examine the "shoulders" of the root crop, where it emerges from the ground. Check for cracks, growths, dark spots, or rot (Kemble, 2022).
• Logic: The root neck is a vulnerable spot. Pathogens of diseases such as Phoma (dry rot) or bacteriosis enter through cracks. Mechanical damage from weeding or pests like mole crickets may also be visible here.

1.6. Examination of the Root Crop Itself (External Appearance)

If you suspect a problem, carefully pull out one or two plants and examine the root crop.

• Purpose: Assess the shape of the root crop, its external color, the presence of side roots, cracks, growths, and ring markings. Here we look for signs of physiological disorders.
• Logic: An ideal root crop should be smooth, evenly colored, and have the shape characteristic of the variety. Forking, curvature, and transverse ring marks are signals of soil problems (waterlogging, compaction), boron deficiency, or that the root has encountered a stone (Nonnecke, 1989; Kemble, 2022).

1.7. Examination of the Root Crop in Cross-Section

This is the "gold standard" of diagnosis. Many diseases and metabolic disorders can only be accurately identified by examining the flesh inside.

• Purpose: Make a transverse or longitudinal cut and study the tissue structure, ring color, and presence of voids and damage.
• Logic: For example, central voids (hollowness) result from sharp fluctuations in moisture (Kemble, 2022). Dark, seemingly "clogged" vessels are characteristic of rots, while fibrousness and lignification indicate over-ripening or excessively high temperatures during the growth period (Nonnecke, 1989; Rana, 2018).

1.8. Examination of the Soil and Root Zone

Conclude the inspection by checking the conditions in which the beet is growing.

• Purpose: Assess moisture, soil structure, and the condition of the root system.
• Logic: Leaf edge burns can be caused by excess salts in the soil. Poor growth is often a consequence of soil compaction, lack of oxygen, root rot, or root damage by pests such as nematodes (Wien & Stützel, 2020; Kemble, 2022).

Important: Record your observations! This will help you not only this season but also next year, to avoid repeating mistakes. Beet diagnostics is detective work, and the correct examination order is your primary tool.

2.1. Boron (B) Deficiency: "Heart Rot"

This is perhaps the most common and insidious problem of young beet tops. Boron is a micronutrient critically important for cell division and the formation of new tissues. It is immobile in the plant, so its deficiency immediately affects the growing point (Rana, 2018).

What it looks like:

• Deformation of the growing point: The central, youngest leaves stop developing normally. They become small, curled, crinkled, and their edges may die off and turn black. In severe cases, the growing point dies completely.
• "Heart Rot": The inner young leaves and the core of the root crop begin to soften, turn brown, and rot. This is clearly visible on a cross-section of the root crop—dark, watery spots in the center.
• Cracks on petioles: Longitudinal cracks appear on the petioles of young leaves, and the petioles themselves become brittle (Kemble, 2022).
• Internal black spots: On a root crop cross-section, you can see dark, dry, or corky spots scattered throughout the flesh, especially in the lighter zones (Rana, 2018).

Why it happens: Boron is involved in the synthesis of pectin substances that bind cell walls. In its deficiency, tissues become loose and easily break down.

What to do: Boron deficiency is easier to prevent than to cure. When the first signs appear, foliar feeding (by leaf) with a solution of boric acid or a preparation like "Solubor" is necessary (Rana, 2018). Root feeding is less effective because boron moves slowly in the soil. In subsequent seasons, apply boron to the soil during bed preparation, especially if you know your soils are poor in this element.

Important Warning: Boron overdose is dangerous! The margin between sufficiency and toxicity is very narrow. Strictly follow the instructions on the product package (Nonnecke, 1989).

2.2. Calcium (Ca) Deficiency

Calcium, like boron, is an immobile element, and its deficiency also hits young tissues. It is responsible for the strength of cell walls and normal root growth.

What it looks like:

• Dieback of the growing point: Young leaves become deformed, and their edges and tips die off (necrosis). The top of the plant may die completely.
• Leaf deformation: Leaves become small, curled, with a characteristic "hooked" bend.
• Slowed growth: The plant looks stunted and low-growing.

What to do: Calcium deficiency is often related not to its absence in the soil, but to its unavailability. This happens due to:

• Lack of moisture: Calcium is absorbed only from the moist soil solution. Irregular watering is the main cause of deficiency (Kemble, 2022).
• Acidic soil (pH below 5.5): In an acidic environment, calcium binds and becomes unavailable to plants.
• Nutrient imbalance: Excess potassium, magnesium, or sodium can interfere with calcium uptake.

Adjust watering and check the soil pH. If necessary, apply liming (dolomite flour or lime) to reduce acidity.

2.3. Viral Infections

Viruses pose a serious threat to beets. They disrupt normal plant growth and development, and their symptoms often manifest on young leaves.

What it looks like:

• Mosaic: Leaves show patches of varying green intensity, alternating with light green or yellow spots (Kemble, 2022).
• Deformation and curling: Leaves become wrinkled, curled, and their size is reduced. Edges may roll upward or downward.
• Vein yellowing: Leaf veins may turn yellow, while the tissue between them remains green (Goldman, 2020).
• Dwarfing: Plants are noticeably stunted; the rosette becomes low-growing, and leaves are small and stiff (Rana, 2018).

Why it happens: Viruses parasitize inside cells, disrupting their normal function. The most common beet viruses are Beet Yellows Virus (BYV) and Beet Curly Top Virus (BCTV). They are transmitted by insect vectors, mainly aphids and leafhoppers (Kemble, 2022; Rana, 2018).

What to do: There is no chemical cure for viral diseases!

• Prevention is the main method. Control aphids and leafhoppers using approved insecticides, especially in the early growth stages (Kemble, 2022).
• Remove diseased plants so they don't become a source of infection for healthy bushes.
• Destroy weeds, especially from the Chenopodiaceae family (lambsquarters, pigweed), which can be virus reservoirs.
• Use resistant varieties, if possible.

2.4. Herbicide Stress

Beets are very sensitive to herbicides, especially to preparations of the 2,4-D and MCPA groups, which are used to control broadleaf weeds in cereal crops. Herbicide stress is not a disease but toxic damage, yet its symptoms are very similar to viral ones.

What it looks like:

• Deformation of young leaves: Leaves become curled, crinkled, resembling "fern" growth. Veins may thicken and become more prominent.
• Epinasty: Leaf petioles bend, curving downward.
• Dieback of the growing point: In severe cases, the growing point may die.

Why it happens: Herbicides (especially systemic ones) mimic plant hormones (auxins), causing uncontrolled, pathological cell growth and division in young tissues (Kemble, 2022).

What to do: The main cause of herbicide stress is drift from neighboring fields during treatment. The best defense is precaution:

• Choose herbicide-tolerant varieties if your fields border cereal crops.
• Carefully plan applications, considering wind direction and using tank mixtures to reduce sensitivity (Wien & Stützel, 2020).
• With mild damage, the plant may recover. Supporting feedings with complex fertilizers can help it recover from stress faster.

So, if you see deformation of young leaves, your main suspects are: boron, calcium, viruses, and herbicides. An accurate diagnosis will become clearer after examining the root crop and analyzing growing conditions.

3.1. Nitrogen (N) Deficiency — "General Starvation"

Nitrogen is the main building block for proteins and chlorophyll. It is highly mobile within the plant.

What it looks like:

• Uniform yellowing (chlorosis): Old leaves gradually become pale green and then uniformly yellow. This process starts at the tips and edges but quickly spreads to the entire leaf blade.
• Slowed growth: The plant looks stunted and low-growing. New leaves emerge small and pale.
• Reddening of veins: In some cases, with acute starvation, veins and petioles may take on a reddish or purple hue (Wien & Stützel, 2020).

Why it happens: Nitrogen is a component of chlorophyll. When it is lacking, the plant stops producing green pigment, breaks down old chloroplasts, and transports nitrogen to young tissues. This is why the lower leaves suffer first.

What to do: Nitrogen deficiency is the easiest problem to fix. Nitrogen fertilization is needed. It is best to use fast-acting forms (urea, ammonium nitrate) or organic liquid fertilizers. Apply the fertilizer as a solution to the root, combined with watering. Remember, excess nitrogen is as harmful as deficiency: it promotes excessive top growth at the expense of the root crop and accumulates nitrates (Nonnecke, 1989).

3.2. Potassium (K) Deficiency — "Marginal Burn"

Potassium is responsible for water balance, sugar transport, and stress resistance. It is also mobile.

What it looks like:

• Yellowing and browning of edges: In old leaves, the tips and edges begin to yellow, then turn brown and dry out. It looks like a "burned" edge. The central part of the leaf may remain green.
• Wrinkling and curling: The leaf blade becomes wrinkled, and edges curl downward or upward (Rana, 2018).
• Weak petioles: Petioles become thin and break easily.

Why it happens: Potassium is necessary for the opening and closing of stomata (respiratory pores on leaves). In its deficiency, the plant cannot effectively regulate water evaporation, and cells at the leaf edges dry out and die.

What to do: Apply potassium fertilizers (potassium sulfate, potassium magnesia). Root feeding with watering is especially effective, as potassium dissolves well. If using ash, note that it contains a lot of potassium but also alkalizes the soil (which can cause other problems, e.g., boron deficiency).

3.3. Magnesium (Mg) Deficiency — "Interveinal Chlorosis"

Magnesium is a component of chlorophyll and participates in photosynthesis. Like potassium, it is mobile and moves to young tissues.

What it looks like:

• Yellowing between veins: A characteristic symptom appears on old leaves: the tissue between the veins turns yellow, while the veins themselves remain bright green. This creates a beautiful but alarming "net-like" pattern.
• Reddening: In some cases, especially in red varieties, the areas between veins may take on a reddish-purple hue (Goldman, 2020).

Why it happens: Magnesium is the central atom in the chlorophyll molecule. When it is lacking, the plant cannot create new chlorophyll molecules and begins to break down old ones in the lower leaves to obtain magnesium.

What to do: Magnesium deficiency often occurs on acidic sandy soils. The best way to replenish it is foliar feeding (spraying on the leaf) with a solution of magnesium sulfate (Epsom salts). This is the fastest way to deliver magnesium to the plant. Dolomite flour (which contains both calcium and magnesium) can also be used when liming the soil (Kemble, 2022).

3.4. Natural Aging

Don't forget that old leaves have their own life cycle. Towards the end of the growing season, they naturally yellow and die off.

What it looks like: Yellowing and wilting occur evenly across the rosette, without spots or apparent deficiency signs on young leaves. This usually happens closer to harvest.

What to do: This is a normal process. If the plant overall looks healthy and the young leaves are bright green, there is no cause for concern.

3.5. Fungal Diseases of Old Leaves

Old leaves, being weakened and often in contact with the soil, are most vulnerable to pathogens. The two most common beet diseases—Cercospora leaf spot and Alternaria leaf spot—start on the lower tier.

What it looks like (differences from nutrient deficiency):

• Spots, not uniform yellowing: Clearly defined spots appear on the leaves, not a uniform color change.
• Cercospora: Spots are round, 2-5 mm in diameter, pale gray or brown with a dark red or purple border. In the center of the spot, small black dots—fungal spores—can be seen. Spots enlarge rapidly and coalesce, causing the leaf to dry up (Rana, 2018).
• Alternaria: Spots are larger, often concentric (ring-shaped), dark brown or black. They may also appear on petioles and root crops (Kemble, 2022).

Why it happens: Old leaves are the "gateway" for infection. They remain wet longer after dew or rain, have more contact with the soil where pathogens live, and have weakened immunity.

What to do: At the first signs of spotting, treatment with fungicides (copper-based products, chlorothalonil, mancozeb) is necessary. But prevention works better: practice crop rotation, remove plant debris in autumn, avoid dense planting for better ventilation, and avoid evening watering on the leaves (Kemble, 2022).

So, seeing yellowing of old leaves, ask yourself: is it uniform yellowing or spotted? If uniform, look for problems with nitrogen, potassium, or magnesium. If spotted, prepare to fight fungal infections. The right answer will save you time and help save your harvest.

4.1. Cold — Temporary Protective Response

This is the most common and, as a rule, harmless cause.

• What it looks like: Leaves, especially young ones, acquire a uniform reddish-purple or magenta hue. This is often noticeable on the underside of the leaf or along the edges of the blade. The coloration may be uniform, without clear boundaries or spots.
• Why it happens: When temperatures drop (especially at night, in spring or autumn), chlorophyll synthesis is disrupted. At the same time, a protective mechanism is activated—the accumulation of anthocyanins. These pigments act as a "sunscreen" and antioxidant, helping the plant survive cold stress (Wien & Stützel, 2020).
• What to do: In most cases, nothing. As soon as temperatures normalize, the coloration will gradually disappear, and the leaves will turn green. If the cold spell is prolonged, you can support the plants with foliar feeding of a complex fertilizer with micronutrients to reduce stress. This is not an urgent measure but rather a preventive one.

4.2. Phosphorus (P) Deficiency — Root Starvation

Phosphorus is a key element for energy metabolism in the plant. It is responsible for the formation of ATP (the universal energy source). Its deficiency manifests characteristically and requires immediate action.

What it looks like:

• Purple-red tint: Leaves take on a dark green with a bluish tinge, which then turns reddish-purple or even bronze. This often starts on the underside of the leaf but can encompass the entire blade.
• Slowed growth: The plant becomes dwarfed, stems thicken, and new leaves emerge small and dark.
• Edge necrosis: In severe cases, the edges and tips of old leaves may turn brown and die (Kemble, 2022; Rana, 2018).

Why it happens: Phosphorus is a relatively immobile element in the soil. Its availability strongly depends on soil temperature and pH. In cold and/or acidic conditions, roots cannot efficiently absorb phosphorus, even if it is present in the soil. The plant, experiencing "energy starvation," activates a protective mechanism, accumulating anthocyanins (Goldman, 2020).

What to do:

• Check soil pH. Phosphorus is best absorbed at pH 6.0–7.0. Acidic soils (pH below 5.5) block its availability. If necessary, apply liming (but remember this is not a quick process).
• Apply phosphorus fertilizers. The best option is liquid or water-soluble forms (e.g., monopotassium phosphate) for quick root feeding. Apply them to the root zone during watering.
• Keep the soil moist, but not waterlogged. Phosphorus is absorbed only from the moist soil solution. When the soil dries out, roots cannot "extract" it.

4.3. Stress (Drought, Waterlogging, Soil Compaction)

Beets, like any plant, react to any extreme conditions (lack or excess of moisture, lack of oxygen in the soil, mechanical damage to roots). This can also cause the accumulation of anthocyanins and, consequently, reddening of the leaves.

What it looks like: Reddening can manifest in various ways: from the edges of the leaf (as in potassium deficiency), but with a purple hue, or as mosaic spots, or covering the entire leaf blade. Other stress symptoms are also visible: leaves may droop, curl, lose turgor (firmness).

Why it happens: Stress disrupts many physiological processes, including chlorophyll synthesis and nutrient uptake. In response, the plant activates protective mechanisms, including the synthesis of anthocyanins (Wien & Stützel, 2020).

What to do: Carefully assess the growing conditions:

• Lack of watering — increase the frequency and volume of watering, especially in hot weather.
• Waterlogging and stagnation — ensure drainage, loosen the row spacing to improve root aeration.
• Soil compaction — carry out deep loosening (without damaging the root crops). This will improve oxygen access to the roots and help restore normal root system function (Kemble, 2022).

4.4. Varietal Anthocyanin Response — When Red Color is Normal

Not all beets should be green! There are varieties where the presence of red or purple pigment in leaves and petioles is a genetic characteristic, not a sign of stress or deficiency.

• What it looks like: Coloration manifests uniformly and predictably for the whole variety. For example, varieties like 'Bull's Blood', 'Chioggia', and many red-leafed varieties have dark red or burgundy leaves and petioles from the very beginning of growth. This coloration does not change with conditions (Goldman, 2020; Freidig & Goldman, 2014).
• Why it happens: This is the result of breeding aimed at enhancing anthocyanin pigmentation. In such varieties, the pigment is constantly present in the cells and serves a decorative function and may also provide additional protection.
• What to do: If you have sown such a variety, simply enjoy the beauty! It is not a problem.

How to distinguish one cause from another?

• Cold: Reddening is temporary, disappears with warming, appears on young leaves, often uniform.
• Phosphorus deficiency: Reddening persists even in warm weather, accompanied by slow growth and small dark leaves. Often starts on the underside of old leaves.
• Stress: Reddening is accompanied by other symptoms (wilting, curling, drooping tops). It is linked to specific weather conditions (drought, waterlogging).
• Varietal characteristic: Coloration is present from the start and is characteristic of the whole variety, independent of external conditions.

Thus, when you see reddened beet leaves, first check the variety (remember what you sowed). If it is not a varietal trait, ask yourself questions about weather and moisture. If there is no stress and it's not cold, check the soil for acidity and feed with phosphorus. A correct diagnosis will help you quickly fix the situation and preserve your harvest.

5.1. Branching (Forking) of the Root Crop

Instead of one central root, the root crop forms two or several "tails" or forks completely.

What it looks like: The root crop has a slingshot, fork, or fan shape. Lateral roots are well-developed and can be as thick as the main root.

Main causes:

1. Mechanical obstructions: The root encountered a stone, a compacted layer of soil, a clod of clay, or a large piece of plant debris (unrotted straw, weed roots). As a result, it is forced to go around the obstacle and branch.

2. Damage to the main root: If the main root was damaged at an early age (e.g., by pests, during weeding, or transplanting), the plant begins to actively develop lateral roots, which eventually become independent root crops. This can also be a consequence of injuries during seedling pricking out.

3. Soil compaction: Too dense, heavy soil (clay) or the formation of a soil crust after watering also hinder the growth of the main root, provoking branching.

What to do: This is a problem easier to prevent than to fix.

• Thorough soil preparation: Deep digging or plowing, removal of stones, roots, and large clods. The soil should be loose and uniform to a depth of at least 25-30 cm.
• Use direct sowing or extremely careful transplanting. Beets do not like root damage. If you grow seedlings, use peat pots to avoid injuring the root system when planting out.
• Regular loosening between rows to prevent the formation of a soil crust (Nonnecke, 1989; Kemble, 2022).

5.2. Flattening (Depressed Shape)

The root crop becomes flattened from top to bottom, like a pancake or a patty.

What it looks like: The root crop grows more in width than in height. The upper part (crown) seems too wide compared to the length.

Main cause: Severe compaction of the topsoil, which prevents the root from growing downward. The root is forced to expand sideways, where there is less resistance. This often occurs on heavy, clayey, or overly waterlogged soils.

What to do: Same as for combating branching: deep soil cultivation, improving its structure (adding sand, peat, humus), ensuring good drainage (Kemble, 2022).

5.3. Ringing (Corrugation) and Coarse Fibrousness

Transverse wrinkles, rings, or growths appear on the surface of the root crop, and the flesh becomes coarse and fibrous.

What it looks like: The root crop appears "ribbed" or "corrugated." Rings may be lighter or darker than the main background. On cross-section, the flesh has a pronounced fibrous structure.

Main causes:

1. Unstable moisture: Sharp fluctuations between drought and waterlogging periods. Root growth either accelerates or slows down, leading to ring formation.

2. High temperatures: Heat (especially above 25–28 °C) accelerates growth, which promotes the formation of coarse, fibrous flesh and intensifies ringing (Rana, 2018; Nonnecke, 1989).

3. Over-ripening: If beets are not harvested on time, the root crop begins to become coarse and woody.

What to do:

• Regular, uniform watering. This is the most important condition for obtaining smooth, juicy root crops. Avoid long periods of soil drying out.
• Mulching. A layer of mulch (straw, mowed grass) helps retain moisture in the soil and smooth out temperature fluctuations.
• Timely harvesting. Harvest beets when they reach commercial maturity, avoiding overgrowth (Kemble, 2022).

5.4. Cracks and Growths on the Root Crop

Deep cracks, especially on the upper part of the root crop, and the appearance of growths or corky formations are another common sign of problems.

What it looks like: Cracks can be both superficial (skin splits) and deep, penetrating the flesh. Sometimes cracks heal but leave a rough scar. Growths resembling cork may also appear.

Main causes:

1. Unstable moisture: As with ringing, sharp fluctuations in moisture (from dryness to waterlogging) cause rapid internal growth that ruptures the outer tissues, which have already hardened.

2. Boron deficiency: This is one of the most common causes of cracks and corky growths. Boron is responsible for the strength of cell walls. When deficient, tissues become brittle and tear easily (Rana, 2018; Nonnecke, 1989).

3. Herbicide stress: Some herbicides, especially 2,4-D derivatives, can cause the formation of growths and ugly, twisted root crops.

What to do:

• Monitor soil moisture (see section 5.3).
• Apply boron. At the first signs of cracks or growths, carry out foliar feeding with a solution of boric acid (1 g per 1 liter of water). For prevention, apply boron to the soil when preparing the bed (1–2 g per 1 m²).
• Avoid herbicides that are sensitive to beets. Use only approved products strictly according to the instructions (Kemble, 2022).

5.5. Deformity (Curvature, Twisting)

The root crop has an irregular, curved shape, often bent like a hook.

What it looks like: The root crop grows not straight but curved, may be S-shaped or spiral-shaped.

Main causes:

1. Mechanical obstructions (see section 5.1). This is the main cause of curvatures.

2. Pest damage: Damage to the main root by wireworms, beetle larvae, or nematodes can also lead to curvature (Wien & Stützel, 2020).

3. Poor soil structure: Too dense, non-uniform soil forces the root to "seek" the path of least resistance.

What to do:

• Deep soil cultivation and removal of obstructions.
• Control of soil pests (crop rotation, use of biological products).
• Improving soil structure (adding organic matter, sand) (Kemble, 2022).

Brief Diagnostic Table of Root Crop Deformities

So, root crop deformation is always the result of adverse conditions that hindered normal growth. Careful examination of the root crop helps to diagnose the problem accurately and correct it in the next season. Remember that most deformities can be prevented with proper agricultural practices.

6.1. Voids (Hollowness) Inside the Root Crop

You cut the root crop, and inside—emptiness, sometimes with loose, cottony tissue, other times just a cavity.

What it looks like: A cavity forms in the center of the root crop or closer to the crown. The surrounding tissue may be normal or slightly softened. Voids can be small or occupy a large part of the internal volume.

Main causes:

1. Unstable moisture (most common cause): Sharp fluctuations between drought and abundant watering or rain. During active growth, cells divide and expand rapidly. If heavy watering follows a long drought, internal tissues begin to grow faster than external ones. This leads to tearing of internal tissues and the formation of voids (Kemble, 2022).

2. Boron deficiency: Boron is necessary for normal cell division and the formation of conducting tissues. When deficient, internal tissues become loose and prone to breakdown, which can also lead to void formation (Rana, 2018).

3. Over-ripening: If beets are not harvested on time, internal tissues may begin to degrade, forming voids.

What to do: The problem is easier to prevent.

• Regular, uniform watering is the key to juicy, dense flesh without voids. Avoid long gaps between waterings, especially during the active root growth period (July-August).
• Mulching the soil helps retain moisture and smooth out fluctuations.
• Timely harvesting. Harvest beets when they reach technical maturity (diameter 5–8 cm for early varieties, 8–12 cm for late varieties).

6.2. Blackening and Dark Spots Inside the Root Crop

This is one of the most alarming and common problems. Inside the root crop, dark, brown, or black areas appear, often with distinct boundaries.

What it looks like:

• "Black heart" or "brown heart": In the center of the root crop, often around the growing point, dark, dry, corky, or watery spots appear. This is a classic symptom of boron deficiency (Rana, 2018; Nonnecke, 1989).
• Dark rings or spots: Dark areas may be scattered throughout the flesh, especially in the lighter zones of the rings. This can also be related to boron deficiency or other metabolic disorders.
• Black, watery spots: This is already a sign of bacterial or fungal rot, which can develop both against the background of boron deficiency and independently (Goldman, 2020).

Why it happens:

• Boron deficiency (main cause): Boron is necessary for normal cell division and the formation of conducting tissues. In its deficiency, internal tissues die off and then darken. This is especially noticeable in areas of active growth—the center of the root crop (Kemble, 2022).
• Bacterial and fungal infections: If the root crop has been injured (e.g., during weeding, by pests, or due to cracks), rot pathogens can enter through the wounds. Rot can also develop against a background of weakened immunity due to boron deficiency.
• Calcium deficiency: A secondary cause, also leading to tissue death in areas of active growth (Goldman, 2020).

What to do:

• Immediate foliar feeding with boron: At the first signs (spots, cracks, dying growing point), spray with a solution of boric acid (1 g per 1 liter of water) or a preparation like "Solubor." This will help stop the development of the deficiency (Rana, 2018).
• Prevention: Apply boron to the soil when preparing the bed (1–2 g per 1 m²), especially on sandy and calcareous soils poor in this element.
• Practice crop rotation and avoid dense planting to reduce the risk of rot development.

6.3. Core Rot (Wet or Dry)

This is a more serious lesion, where the internal tissues completely decompose, becoming soft, slimy, or dry and crumbly.

What it looks like: On cut, the core of the root crop has turned into dust, sometimes with an unpleasant odor. The flesh may be brown, black, or even pinkish (Kemble, 2022).

Main causes:

1. Fungal and bacterial infections (Phoma, bacteriosis): Pathogens enter through cracks or through dead tissue (e.g., due to boron deficiency) and decompose the root crop from the inside.

2. Damage during harvesting and storage: If you injure the root crop during digging, rot pathogens can enter through the wound during storage.

3. Improper storage conditions: Too high temperature and humidity in the storage facility promote rot development (Nonnecke, 1989).

What to do: This is a problem that needs to be prevented.

• Carefully cull damaged and suspicious root crops when storing.
• Ensure proper storage conditions: temperature 0–2 °C, humidity 90–95%, good ventilation.
• Practice crop rotation and remove plant residues from the field to avoid accumulating disease pathogens in the soil.

6.4. Disruption of the Ring Structure and Paleness

In a healthy beet, a cross-section shows distinct, contrasting dark red and light rings. If this structure is disrupted, it signals problems.

What it looks like:

• Pale, blurred rings: Rings appear pale pink or white, contrasting poorly with each other.
• Excessively wide light rings: This indicates excessive growth of conducting tissues.
• "Zoning" (pronounced ringiness): Sometimes rings become too bright and contrasting, which is also a disorder (Goldman, 2020; Rana, 2018).

Why it happens:

• High temperatures: In heat (above 25 °C), pigment synthesis (betacyanin) slows down, and rings become pale. Heat also disrupts the normal alternation of rings (Rana, 2018).
• Moisture fluctuations: As with voids, sharp moisture fluctuations disrupt uniform growth, which affects the ring structure.
• Varietal characteristics: Some varieties (e.g., 'Chioggia') have more pronounced ringiness than others (Goldman, 2020).

What to do:

• Regular watering (see section 6.1) helps maintain a normal ring structure.
• Choose varieties adapted to your climate. For hot regions, varieties tolerant to high temperatures are better suited.
• Avoid overheating the soil — mulching or shading (on particularly hot days) can help preserve root quality.

6.5. Fibrousness and Lignification

On cut, the flesh seems coarse, fibrous, hard like wood.

What it looks like: The flesh has a pronounced fibrous structure, cuts poorly, and tastes tough.

Main causes:

1. Over-ripening: The most common cause. Beets overgrow, and their tissues become coarse.

2. High temperatures: Heat accelerates the processes of aging and lignification of tissues (Nonnecke, 1989).

3. Moisture deficiency: Drought also contributes to the flesh becoming fibrous and tough.

4. Potassium deficiency: Potassium is responsible for the succulence and turgor of tissues. When deficient, the flesh becomes drier and tougher (Wien & Stützel, 2020).

What to do:

• Timely harvesting. Do not keep beets in the ground too long.
• Regular watering, especially during dry periods.
• Apply potassium fertilizers (potassium sulfate, potassium magnesia) during the active root growth period.

Brief Diagnostic Table of Internal Root Crop Problems

Internal examination of the root crop is your main diagnostic weapon. It allows you to look inside and see what is hidden from the eye. If you learn to "read" these internal signals, you can significantly improve the quality of your harvest and prevent many problems in the future.

7.1. The Three "Pillars" of Diagnosis: Disease, Pest, Physiology

To understand what you are dealing with, you need to assess the problem according to three main parameters:

1. Nature of symptoms: What exactly does the damage look like? Spots, rot, deformation, bites?

2. Spread: Is the damage localized (one leaf, one plant) or widespread (all plants, the whole field)?

3. Dynamics: How quickly is the problem developing? Suddenly, gradually, or has it been noticeable all along?

7.2. How to Distinguish a Disease (Infection) from a Physiological Disorder

This is the most difficult distinction because external symptoms (spots, yellowing, wilting) can look very similar.

Disease (fungal, bacterial, viral):

• Symptoms: Spots have distinct boundaries, often a specific shape (rings, halos, ulcers). On the spots, you can often see sporulation—black dots (pycnidia), gray or pinkish coating, fluffy mycelium (especially in damp weather). Rots are often accompanied by an unpleasant odor (Kemble, 2022; Rana, 2018).
• Spread: Often starts with individual plants or with the lower, old leaves in contact with the soil. Then spreads across the field from the source of infection. Unevenly, may skip individual bushes.
• Dynamics: Can develop quickly, especially in weather favorable for the pathogen (damp, cool). Often appears after rains or prolonged wetness.
• Examples: Cercospora leaf spot (spots with purple border), Alternaria leaf spot (concentric spots), Phoma (dry rot with zones), viral mosaic (spotting and deformation of young leaves).

Physiological Disorder (nutritional deficiency, stress, weather):

• Symptoms: Spots or color changes usually have blurred boundaries, no clear pattern. Deformations (curling, crinkling) are often symmetric and manifest on all plants in roughly the same way. There are no signs of sporulation or rot (Goldman, 2020; Wien & Stützel, 2020).
• Spread: Often is widespread—all plants in the field or bed look roughly the same. Localized in specific zones of the field (e.g., on poor areas, on top of a hill, in a hollow).
• Dynamics: Develops gradually (deficiency accumulates over weeks) or suddenly in response to a sharp change in weather (frost, drought, waterlogging).
• Examples: Nitrogen deficiency (uniform yellowing of old leaves), boron deficiency (dying growing point and cracks), drought burn (leaf edges turn brown), cold reddening (temporary).

Table 1: Disease vs. Physiology

7.3. How to Distinguish a Pest from Disease and Physiology

Pests leave the most characteristic "signatures," which are hard to confuse with anything else.

Pest:

• Symptoms: Visible mechanical damage—bites, gnawed areas, tunnels, mines, chewed leaf edges. Often you can notice excrement (black or green dots) or webs (mites) (Kemble, 2022).
• Spread: Often starts from the edge of the field or from individual plants. Some pests (aphids, mites) create colonies that are easily visible on the underside of leaves.
• Dynamics: Appears suddenly, often after warm weather. Can multiply quickly and spread to neighboring plants.
• Main sign: Presence of the pest itself (or its traces—eggs, larvae, skins). If you see an insect or its larva—it's a pest.
• Examples: Leaf beetle larvae (chew leaf edges), cutworm caterpillars (eat holes), aphids (colonies on leaf undersides, sticky honeydew), nematodes (swellings and galls on roots), wireworms (tunnels and damage to root crop), leaf miners (pale "trails" inside the leaf).

7.4. What to Do If You Cannot Determine the Exact Cause?

Sometimes even an experienced gardener may have doubts. In this case:

1. Don't rush into treatment. Do not apply fungicides or insecticides until you are sure—it may be useless and even harmful.

2. Intensify observation. Check the plants every day to see how the symptoms develop.

3. Conduct "field tests":

• Nutritional deficiency: Try foliar feeding with a complex fertilizer containing micronutrients. If symptoms begin to diminish within 3–5 days, then the cause was nutritional.
• Pests: Turn over a leaf and carefully inspect the underside. Use a magnifying glass. Set traps (yellow sticky traps for aphids).
• Diseases: Place an affected leaf in a moist chamber (e.g., a plastic bag). If fungal growth appears on the spots within 1–2 days, it's a disease.
• Keep an observation diary. Record when symptoms appeared, what the weather was like, and what you did (feeding, watering). This will help you see patterns in the next season.
• Seek help from local specialists (agronomists, consultants, agricultural forums). A good photo with a detailed close-up and an overall view of the plant can help with remote diagnosis.

Conclusion

Beet diagnostics is not magic but a systematic approach. By learning to distinguish diseases, pests, and physiological disorders, you will be able to act quickly and effectively. Remember the three main principles:

1. The symptom speaks of age — a problem with young leaves differs from a problem with old ones.

2. Appearance is the key to diagnosis — distinct spots = infection, blurred = physiology, damage = pest.

3. Widespread and dynamics are your clues — how quickly and how widely the problem spreads.

Use this system as a map, and your garden will be under your reliable control.