How to treat cucumbers for spider mites in a greenhouse?

Understanding Spider Mites in Greenhouse Cucumbers

Identifying a Spider Mite Infestation

Visual Signs on Leaves

Spider mites on cucumber vines in greenhouse production reveal their presence primarily through leaf damage. Early detection relies on careful observation of foliage rather than waiting for severe infestations.

Typical visual indicators include:

Tiny, pale specks where chlorophyll has been consumed, creating a stippled or stippling pattern across the leaf surface.
Fine, silvery or bronze discoloration that spreads from leaf margins toward the center.
Slightly bronzed or yellowish leaf tissue, often more pronounced on the underside.
Fine webbing, usually noticeable when leaves are examined closely, especially along leaf veins and in the crown of the plant.
Irregularly shaped, tiny white or light-colored spots where the mite’s feeding has caused cell collapse.

Progression of symptoms follows a predictable sequence. Initial stippling advances to larger bronzed patches, which then coalesce into extensive areas of necrosis. As the population grows, webbing becomes dense enough to be visible without magnification, and leaf curling may develop due to loss of turgor.

Differentiating spider mite damage from other stresses is essential. Nutrient deficiencies typically produce uniform chlorosis, while fungal leaf spots present as raised lesions with distinct margins. The combination of stippling, bronzing, and fine webbing on the leaf underside uniquely identifies spider mite activity.

Regular scouting, focusing on the undersides of lower leaves, allows growers to record the onset of these signs and implement control measures before yield loss escalates.

Webbing Presence

Webbing on cucumber vines signals active spider‑mite colonies. The silk threads appear as fine, white or yellowish sheets covering leaf surfaces, petioles, and sometimes fruit. Presence of webbing indicates that mite populations have reached a level where feeding damage is likely to spread rapidly.

Inspect plants weekly, focusing on the undersides of leaves where webs accumulate. Use a handheld magnifier or a smartphone camera with macro capability to confirm mite activity under the silk. Remove visible webs with a soft brush or a gentle stream of water; this reduces mite shelter and improves spray coverage.

Implement control measures promptly:

Apply a miticide labeled for spider mites, following label rates and ensuring thorough coverage of all leaf surfaces, including the webbed areas.
Introduce predatory mites (e.g., Phytoseiulus persimilis) to establish biological pressure on the pest.
Increase greenhouse ventilation and lower relative humidity to create less favorable conditions for mite reproduction.
Rotate cucumbers with non‑host crops for at least one cycle to disrupt mite life cycles.

Monitor webbing after treatment. A decline in silk density within 3–5 days suggests effective control; persistent or expanding webs require a second miticide application or augmentation of biological agents. Continuous observation prevents secondary infestations and protects cucumber yield.

Plant Damage Symptoms

Spider mite infestations on greenhouse cucumbers produce distinct visual cues that signal plant stress. Early signs appear as tiny, pale specks on the leaf surface where mites feed. These stipples coalesce into larger translucent patches, giving foliage a stippled or mottled appearance. As feeding intensifies, the affected tissue turns yellow and eventually bronzes, especially on the undersides of leaves where mite populations concentrate.

The most reliable indicator of severe damage is the formation of fine webbing. Web strands are visible along leaf veins, between leaflets, and on the fruit surface. Webbing often precedes leaf drop; heavily infested leaves curl, shrink, and abscise, reducing photosynthetic capacity and compromising fruit development.

Additional symptoms include:

Stunted vine growth and reduced internode length.
Small, misshapen cucumbers with uneven skin texture.
Increased susceptibility to secondary pathogens, manifested as necrotic lesions or fungal growth on damaged tissue.

Monitoring these symptoms enables timely intervention, preventing yield loss and maintaining greenhouse crop health.

Why Spider Mites Thrive in Greenhouses

Ideal Environmental Conditions

Optimal control of spider mites on cucumber crops in a greenhouse depends on maintaining specific environmental parameters. Deviations create favorable conditions for mite reproduction and reduce the efficacy of biological agents.

Temperature: keep daytime air temperature between 22 °C and 28 °C; night temperature should not drop below 18 °C. This range supports cucumber growth while limiting mite population growth rates.
Relative humidity: maintain 60 %–70 % RH. Humidity above 70 % suppresses mite egg viability; below 60 % accelerates development.
Air circulation: provide continuous gentle airflow, achieving 0.2–0.3 m s⁻¹ across the canopy. Adequate circulation prevents microclimates where mites can proliferate and improves distribution of predatory mites.
Light intensity: ensure photosynthetic photon flux density of 300–500 µmol m⁻² s⁻¹. Sufficient light promotes vigorous foliage, reducing stress‑induced susceptibility to infestation.

Consistent temperature and humidity also create optimal conditions for introduced predatory mites such as Phytoseiulus persimilis and Neoseiulus californicus. These agents require a minimum of 20 °C and 70 % RH to reproduce effectively. Aligning greenhouse climate with these thresholds enhances biological control, reduces reliance on chemical treatments, and sustains cucumber productivity.

Lack of Natural Predators

The greenhouse environment often lacks the predatory insects that naturally suppress spider mite populations on cucumber crops. Without these biological controls, mite colonies expand rapidly, causing extensive leaf damage, reduced photosynthetic capacity, and lower yields.

To compensate for the absence of natural enemies, growers must implement alternative measures:

Introduce commercially available predatory mites (e.g., Phytoseiulus persimilis, Neoseiulus californicus) and maintain release schedules that match infestation levels.
Employ banker‑plant systems that harbor predatory species, providing a continuous source of biocontrol agents.
Apply selective miticides that spare beneficial arthropods, rotating active ingredients to prevent resistance.
Optimize greenhouse climate (temperature, humidity, ventilation) to create conditions unfavorable for mite reproduction while remaining suitable for cucumbers.

Monitoring programs should track mite density and predator establishment daily, allowing timely adjustments to release rates, chemical applications, or environmental parameters. This integrated approach offsets the deficit of indigenous predators and preserves cucumber health.

Treatment Methods for Spider Mites

Non-Chemical Approaches

Cultural Practices

Effective cultural tactics reduce spider‑mite pressure on cucumber production in protected environments. Cleanliness, environmental regulation, and plant management create conditions unfavorable to mite development.

Remove plant debris and fallen leaves each season.
Maintain temperatures between 20 °C and 25 °C; lower temperatures slow mite reproduction.
Keep relative humidity above 60 % during the day; high humidity discourages mite activity.
Apply frequent, gentle overhead watering to wash mites from foliage.
Prune densely shaded or heavily infested sections to improve air flow and light penetration.
Rotate cucumbers with non‑cucurbit crops or fallow periods to interrupt mite life cycles.
Select cultivars with documented resistance or tolerance to spider mites.

Sanitation eliminates overwintering sites. Temperature and humidity control directly affect mite biology, limiting population growth. Regular wetting removes individuals before they establish colonies. Pruning and adequate spacing enhance microclimate stability and reduce shelter. Crop rotation prevents buildup of mite reservoirs in the soil and surrounding vegetation. Resistant varieties provide a genetic barrier, decreasing reliance on chemical interventions. Together, these practices form a comprehensive, non‑chemical strategy for managing spider mites in greenhouse cucumber production.

Biological Control «Beneficial Insects»

Effective management of spider mite infestations on greenhouse-grown cucumbers relies on the strategic use of predatory insects. These natural enemies suppress mite populations without chemical residues, preserving crop quality and marketability.

The most reliable agents are predatory mites of the Phytoseiidae family, such as Phytoseiulus persimilis and Neoseiulus californicus. They locate spider mites by detecting webbing and plant volatiles, then consume all mobile stages. Release rates of 1 – 2 predators per adult spider mite ensure rapid colonization; higher densities may be needed in severe outbreaks.

Supplementary predators include:

Lady beetle larvae (Coccinellidae) – effective against spider mite eggs and early instars.
Green lacewing larvae (Chrysoperla spp.) – consume mite eggs and small nymphs.
Minute pirate bugs (Orius spp.) – target both spider mites and secondary pests.

Optimal conditions for predator performance:

Temperature: 20 °C – 30 °C; avoid extreme heat (>35 °C) that reduces longevity.
Relative humidity: 60 % – 80 %; low humidity impairs mite mobility and predation.
Avoid broad-spectrum insecticides; select products labeled safe for beneficials or use botanical sprays with minimal toxicity.

Implementation steps:

Inspect plants weekly for mite presence and predator activity.
Introduce predatory mites when spider mite counts exceed 5 – 10 per leaf.
Distribute predators evenly across the canopy, using a fine mist sprayer or shaker boxes.
Maintain environmental parameters within the ranges above for at least two weeks to allow predator establishment.
Re‑introduce additional releases if mite populations rebound after a decline.

Integrating beneficial insects with cultural practices—such as removing heavily infested leaves, regulating ventilation to reduce humidity spikes, and providing banker plants for predator sustenance—enhances control durability. Regular monitoring and timely releases keep spider mite numbers below economic thresholds, ensuring healthy cucumber production in the greenhouse environment.

Horticultural Oils and Soaps

Horticultural oils and soaps provide direct contact control of spider mites on greenhouse cucumber crops. They consist of refined petroleum, plant‑derived, or synthetic oils, and potassium‑ or sodium‑based soaps formulated to penetrate the mite cuticle, causing desiccation and death without systemic activity.

Selection criteria focus on oil viscosity, phytotoxicity rating, and compatibility with cucumber foliage. Low‑viscosity mineral or neem oils are suitable for young leaves, while higher‑viscosity horticultural oils address dense canopies. Soaps should be potassium‑based, free of additives that could harm tender tissue.

Application guidelines:

Dilute according to label instructions, typically 0.5–2 % active ingredient.
Apply in the early morning or late afternoon to avoid rapid drying and leaf burn.
Ensure thorough coverage of leaf undersides, where spider mites reside.
Repeat every 5–7 days until mite counts fall below economic thresholds.
Conduct a 24‑hour test on a small plant section before full‑scale treatment to confirm tolerance.

Safety considerations include wearing protective gloves and goggles, preventing drift onto beneficial insects, and avoiding use during high temperatures (>30 °C) or intense sunlight, which increase phytotoxic risk. Integrate oils and soaps with cultural practices—such as humidity regulation, adequate spacing, and removal of infested debris—to reduce mite pressure and delay resistance development.

Chemical Control Options

Understanding Pesticide Types

Effective control of spider mites on greenhouse cucumbers depends on selecting the appropriate pesticide class. Contact miticides, such as pyrethroids (e.g., bifenthrin) and carbamates (e.g., carbaryl), act quickly on exposed mites but may lose efficacy as resistance develops. Systemic products, including neonicotinoids (e.g., imidacloprid) and avermectins (e.g., abamectin), are absorbed by plant tissue and reach mites feeding on sap, providing longer residual activity. Oil‑based formulations (horticultural oil, neem oil) and insecticidal soaps disrupt mite cuticles, offering a non‑chemical option with minimal residue concerns.

Key considerations when applying these agents:

Rotate between chemical classes to delay resistance.
Observe label‑specified pre‑harvest intervals to ensure marketable produce.
Verify greenhouse ventilation and temperature compatibility, as some products lose potency under high humidity.
Combine with biological agents (predatory mites, Bacillus thuringiensis) for integrated pest management.

Understanding each pesticide type’s mode of action, persistence, and safety profile enables precise scheduling and reduces the likelihood of crop damage while maintaining mite suppression.

Safe Application Techniques

Effective control of spider mites on greenhouse cucumbers requires precise, low‑risk application of treatments. Use products labeled for vegetable crops and approved for enclosed environments. Verify the registration number and expiration date before mixing.

Measure the active ingredient according to the label; avoid exceeding the maximum concentration.
Dilute the product in clean, lukewarm water; stir gently to prevent foam formation.
Apply with a fine‑mist sprayer that produces droplets of 30–50 µm; this size ensures leaf coverage while minimizing drift.
Treat the undersides of leaves where mites reside; rotate the spray pattern to reach all canopy layers.
Conduct applications in the early morning or late afternoon; temperatures should remain between 15 °C and 25 °C, and relative humidity above 60 % to enhance contact.
Allow a minimum interval of 24 hours between successive sprays; observe the pre‑harvest interval specified on the label.

Personal protective equipment (PPE) is mandatory. Wear chemical‑resistant gloves, goggles, and a half‑mask respirator with appropriate cartridges. Change outer clothing before leaving the greenhouse to prevent cross‑contamination.

Record each treatment: date, product name, concentration, volume applied, and environmental conditions. Review the log weekly to detect patterns, adjust timing, and confirm compliance with safety regulations.

Rotation of Active Ingredients

Effective spider mite management on greenhouse cucumbers relies on systematic rotation of pesticide active ingredients. Repeated use of a single mode of action selects resistant mite populations, reducing control efficacy and increasing chemical input. Rotating compounds with different biochemical targets disrupts resistance development and sustains long‑term productivity.

Key principles for active‑ingredient rotation:

Identify at least three distinct mode‑of‑action groups (e.g., acaricidal pyrethroids, organophosphates, and spirotetramat‑based systemic agents).
Apply each group no more frequently than the label‑specified interval, typically 7–14 days, and avoid using the same group consecutively.
Incorporate a non‑chemical tactic, such as predatory mite releases (e.g., Phytoseiulus persimilis), between chemical applications to reduce mite pressure.
Record product name, active ingredient, application date, and dosage in a resistance‑management log to verify compliance with rotation schedules.

When selecting products, consider the following attributes:

Contact acaricides – rapid knock‑down, useful for early infestations; limited residual activity, requiring follow‑up treatments.
Systemic acaricides – absorbed by foliage, providing protection to new growth; risk of residues, necessitate pre‑harvest interval adherence.
Insect growth regulators – disrupt mite development, offering extended control; best applied after population monitoring confirms juvenile dominance.

Implementing rotation demands strict adherence to label rates, calibrated spray equipment, and proper coverage to ensure uniform deposition. Monitoring mite counts before each application confirms whether a switch to a different mode of action is warranted. Failure to rotate appropriately accelerates resistance, leading to increased crop loss and higher production costs.

Prevention Strategies

Regular Monitoring and Early Detection

Daily Plant Inspection

Daily plant inspection is the first line of defense against spider mites on greenhouse cucumbers. Early detection limits population growth, reduces pesticide applications, and protects yield quality.

Inspect each plant every morning before watering. Use a 10‑× 15 cm white card or a hand lens (10× magnification) to examine the undersides of leaves. Look for the following indicators:

Fine webbing connecting leaf veins
Yellow or bronze speckling on leaf tissue
Tiny moving dots that become more apparent when the leaf is disturbed
Stippled or stippled leaf edges

Record observations on a simple log sheet. Note the cultivar, tray location, and date. If several plants in the same aisle show symptoms, flag the area for immediate action.

When the number of mites exceeds the economic threshold (approximately 5 mites per leaf quadrant), implement control measures without delay. Options include:

Spraying a miticide approved for cucumber production, following label rates and re‑entry intervals.
Introducing predatory mites (e.g., Phytoseiulus persimilis) at a ratio of 1 predator per 5 spider mites.
Adjusting environmental parameters—lowering relative humidity below 60 % and increasing air circulation—to create unfavorable conditions for mite reproduction.

Consistent documentation creates a trend analysis that helps predict outbreak cycles and refine inspection frequency. By integrating systematic daily checks with rapid response protocols, greenhouse operators maintain cucumber health and minimize spider‑mite damage.

Using Yellow Sticky Traps

Yellow sticky traps provide a reliable method for monitoring and reducing spider‑mite populations on cucumber plants cultivated in greenhouse environments. The adhesive surface captures adult females and dispersing nymphs, interrupting the reproductive cycle and lowering overall pressure on the crop.

Effective deployment requires attention to trap placement, density, and maintenance. Position traps at canopy height where leaves are most densely packed, ensuring visibility of the bright yellow hue that attracts spider mites. Install one trap per square meter of growing area, adjusting upward in heavily infested zones. Secure traps on a stable support to prevent contact with foliage, which could cause accidental capture of beneficial insects.

Replace traps regularly to maintain adhesive potency. A replacement interval of 7–10 days prevents saturation with captured insects and debris. Inspect traps during each inspection cycle; a sudden increase in captures signals a rising mite population and may trigger additional control measures, such as targeted miticide applications or the introduction of predatory mites.

Integrating yellow sticky traps with cultural practices enhances efficacy. Maintain optimal humidity (60–70 %) and temperature (22–26 °C) to discourage mite reproduction while preserving plant health. Remove heavily infested leaves promptly to reduce the source of mobile mites. Combine trap data with threshold values—typically 5–10 mites per trap per day—to decide when supplemental interventions become necessary.

By adhering to precise placement, consistent replacement, and data‑driven decision making, yellow sticky traps serve as a cornerstone of an integrated pest‑management strategy for cucumber production in greenhouse settings.

Maintaining Greenhouse Hygiene

Cleaning Practices

Effective pest control in cucumber production requires rigorous sanitation. Regular removal of plant debris prevents spider mite colonies from establishing hidden refuges. Discard any wilted or heavily infested leaves in sealed bags and replace with clean material.

Maintain tool hygiene by washing pruning shears, trays, and support frames with a detergent solution after each use. Rinse thoroughly, then soak in a 0.5 % sodium hypochlorite solution for five minutes before drying. This eliminates residual mite eggs and reduces cross‑contamination.

Greenhouse surfaces demand frequent cleaning. Sweep floors and benches to eliminate dust that shelters mobile stages of the mite. Follow with a mop soaked in a mild surfactant mixed with water; ensure the solution reaches cracks and crevices. Allow surfaces to dry completely before re‑entering the production area.

Implement a schedule that integrates the following tasks:

Daily inspection and removal of visibly infested foliage.
Weekly washing of all cultivation containers with warm, soapy water.
Bi‑weekly deep cleaning of benches, gutters, and ventilation ducts.
Monthly disinfection of the entire greenhouse using an approved acaricide‑compatible sanitizer.

Air circulation systems should be checked for blockages. Clean filters and vents every two weeks to prevent dust accumulation, which can harbor mite eggs. Proper airflow also discourages mite proliferation by reducing leaf humidity.

Adopt these cleaning protocols consistently to suppress spider mite populations and support healthy cucumber growth in a controlled environment.

Sterilizing Equipment

Sterilizing all equipment that contacts cucumber plants is essential for breaking the life cycle of spider mites in a greenhouse. Contaminated tools, trays, and irrigation components can harbor eggs and mobile stages, leading to rapid reinfestation after chemical or biological treatments.

Disassemble sprayers, pruning shears, and harvesting baskets. Submerge parts in a 10 % bleach solution for 10 minutes, then rinse thoroughly with clean water.
Soak seedling trays and plastic containers in hot water at 70 °C for at least 5 minutes. Follow with a brief dip in a quaternary ammonium disinfectant, according to the manufacturer’s concentration guidelines.
Clean greenhouse benches and work surfaces with a detergent‑based cleaner, rinse, and apply a residual fungicide that also acts against mite eggs. Allow the surface to dry completely before reuse.
Treat irrigation lines by flushing with a 2 % hydrogen peroxide solution, followed by a sterile water rinse. Replace any worn tubing that shows biofilm buildup.
Store all sterilized items in a sealed, dust‑free area. Use dedicated racks or trays labeled for mite‑free equipment to prevent cross‑contamination.

Regular implementation of these sterilization steps, combined with monitoring and targeted mite control measures, reduces the risk of persistent spider mite populations on cucumber crops.

Environmental Management

Humidity Control

Effective humidity management is essential for suppressing spider mite populations on cucumber crops cultivated in greenhouse environments. Spider mites thrive under low‑humidity conditions; maintaining higher relative humidity disrupts their reproductive cycle and reduces leaf‑surface colonization.

Target a relative humidity range of 70 %–80 % during the day and avoid rapid fluctuations. Use the following practices to achieve and sustain this environment:

Install fine‑mist or fogging systems that emit a gentle, continuous spray, raising ambient moisture without wetting foliage excessively.
Employ humidifiers with hygrometric feedback, calibrating output to keep humidity within the desired band.
Seal gaps in the greenhouse structure, including doors, vents, and roof panels, to prevent dry external air intrusion.
Adjust ventilation rates; reduce exhaust fan speed during peak heat periods, then increase airflow briefly in the evening to prevent condensation.
Monitor humidity with calibrated sensors placed at canopy height, recording data at least hourly to detect deviations promptly.

Combine humidity control with complementary cultural tactics—such as balanced irrigation, adequate spacing, and regular removal of heavily infested leaves—to enhance overall mite management effectiveness. Consistent adherence to these humidity parameters creates an environment unfavorable to spider mites while supporting healthy cucumber growth.

Temperature Regulation

Effective temperature management reduces spider‑mite reproduction on cucumber crops in greenhouse production. Maintaining conditions outside the optimal range for the pest suppresses population growth and enhances the efficacy of biological and chemical controls.

Keep daytime air temperature between 18 °C and 22 °C; temperatures above 25 °C accelerate mite development.
Nighttime temperatures should not fall below 12 °C, as low temperatures delay cucumber growth and weaken plant defenses.
Use thermostatically controlled heating to raise night temperatures when ambient levels drop.
Deploy ventilation fans or evaporative cooling to lower daytime temperatures if they exceed 25 °C.
Monitor temperature continuously with digital sensors; adjust climate controls within 1 °C of target values to avoid fluctuations that favor mite proliferation.

Post-Treatment Care and Long-Term Management

Restoring Plant Health

Fertilization

Proper fertilization influences cucumber vigor and susceptibility to spider mites in greenhouse production. Excessive nitrogen accelerates leaf growth, creating dense foliage that shelters mites and reduces plant resistance. Conversely, balanced nutrient supply strengthens plant defenses and limits mite reproduction.

Key fertilization practices for mite management:

Apply a moderate nitrogen rate (e.g., 150–180 kg N ha⁻¹) split into early‑season and mid‑season applications.
Include adequate potassium (80–100 kg K₂O ha⁻¹) to enhance leaf toughness and improve stress tolerance.
Supplement with calcium (30–40 kg Ca ha⁻¹) to reinforce cell walls and delay mite colonization.
Use micronutrient blends containing zinc and manganese at recommended levels to support enzymatic functions linked to pest resistance.
Avoid high‑nitrogen foliar sprays during peak mite activity; prefer low‑concentration, balanced formulations if foliar feeding is necessary.

Regular tissue analysis guides adjustments. When nitrogen indices exceed optimal ranges, reduce subsequent applications and increase potassium or calcium to restore balance. Monitoring leaf coloration and growth rate helps detect over‑fertilization before mite outbreaks intensify.

Watering Schedule

A precise irrigation program reduces spider‑mite colonization on greenhouse cucumbers by limiting leaf surface humidity and disrupting mite development cycles.

Maintain soil moisture at 70 % of field capacity. Apply water early in the morning to allow foliage to dry before dusk, preventing the cool, humid microclimate that favors mite reproduction.

Days 1‑3: Light watering (2 L m⁻²) every 24 h. Soil moisture target: 60‑65 %.
Days 4‑7: Moderate watering (3 L m⁻²) every 48 h. Soil moisture target: 70 %.
Days 8‑14: Heavy watering (4 L m⁻²) every 72 h. Soil moisture target: 75‑80 %. Increase frequency if temperature exceeds 30 °C.
Days 15‑21: Return to light watering (2 L m⁻²) every 48 h. Monitor leaf wetness; keep leaf surfaces dry for at least 6 h after irrigation.

Use drip emitters positioned 10 cm above the soil surface to avoid direct contact with foliage. Flush the system weekly with a 0.5 % potassium bicarbonate solution to reduce mite populations on the emitters.

Record soil moisture, ambient temperature, and relative humidity daily. Adjust volumes by ±0.5 L m⁻² if measurements deviate from target ranges, ensuring consistent plant vigor while suppressing spider‑mite proliferation.

Preventing Recurrence

Ongoing Monitoring

Effective control of spider mites on greenhouse cucumbers depends on continuous observation of pest pressure and plant health. Regular scouting provides the data needed to adjust interventions before infestations reach damaging levels.

Inspect each tray or row at least twice weekly; increase to three times during warm periods when mite reproduction accelerates.
Examine the undersides of leaves with a 10‑20× hand lens; record the number of live mites, eggs, and webbing per leaf.
Use sticky traps or blue‑yellow monitoring cards placed at canopy height; replace traps every 7 days and count captured mites.
Maintain temperature and humidity logs; correlate spikes in mite counts with environmental conditions to predict outbreak windows.
Set action thresholds (e.g., ≥5 mobile mites per leaf or ≥10 mites per trap); trigger targeted miticide applications or biological releases when thresholds are exceeded.

Document all observations in a centralized spreadsheet, noting date, location, sampling method, and counts. Review trends weekly to identify hotspots and evaluate the efficacy of previous treatments. Adjust spray schedules, release rates of predatory insects, or environmental controls based on the recorded data, ensuring that interventions remain proportional to the measured pest pressure.

Integrated Pest Management «IPM» Plan

An effective Integrated Pest Management (IPM) plan for cucumber production in greenhouse environments targets spider mite infestations through a sequence of preventive, monitoring, biological, and chemical actions.

Regular scouting establishes baseline mite populations and identifies hotspots. Use a 10‑cm square leaf sample from each tier, inspect under a magnifier, and record the number of mites per leaf. Thresholds of 2–3 mites per leaf on the lower tier and 5–7 mites per leaf on the upper tier trigger intervention.

Cultural practices reduce mite colonization. Maintain relative humidity between 60 % and 70 % to discourage mite development. Space plants to improve air circulation and reduce leaf wetness. Rotate cucumber varieties annually and remove plant debris after each crop cycle.

Biological agents suppress mite numbers without residue concerns. Release predatory mites (e.g., Phytoseiulus persimilis or Neoseiulus californicus) at a rate of 10–20 adults per m² when thresholds are exceeded. Apply entomopathogenic fungi such as Beauveria bassiana according to label recommendations, preferably in the early evening to protect against UV degradation.

Chemical measures serve as a last resort. Select miticides with low toxicity to beneficial organisms, such as abamectin or spirodiclofen, and rotate active ingredients to prevent resistance. Apply the minimum effective concentration, avoid overlapping applications, and observe a pre‑harvest interval of at least 7 days.

Post‑treatment evaluation confirms control efficacy. Re‑sample the same leaf area after 3–5 days, compare mite counts to pre‑treatment levels, and adjust future releases of biological agents accordingly. Document all observations, interventions, and outcomes in a centralized log for continuous improvement of the IPM program.