Cultivation of Sweet Pepper in Greenhouses: A Complete Production Guide Including Mini Peppers

Sweet pepper (Capsicum annuum) and the increasingly popular mini pepper can be a great choice for greenhouse growers.

This guide covers the full production cycle from variety selection through harvest.

Variety Selection

Variety choice is the single most important decision in a pepper program. Key selection criteria include:

• Fruit type — standard block (California type), elongated (lamuyo), or mini pepper. Each has distinct market requirements for size, wall thickness, and color.
• Color — red, yellow, and orange are the primary commercial colors. Green peppers are immature fruit of any color variety. Red varieties typically have the longest production cycle; yellow and orange are intermediate.
• Disease resistance — prioritize resistance to Phytophthora capsici (Pc), Tobacco mosaic virus (Tm:0,1,2), Tomato spotted wilt virus (TSWV), and Leveillula taurica powdery mildew (Lv)
• Yield and fruit set — evaluate fruit set under low light and high temperature conditions relevant to your production season
• Shelf life and firmness — critical for export and long-distance distribution channels

Paramount Seeds Greenhouse Pepper Varieties

The following varieties are available from Paramount Seeds. Click any variety name to view full details and order.

Red Bell Pepper

Variety	Key Notes	Disease Resistance
Sprinter F1	Blocky red; not sensitive to BER or russetting	Tm 0–3
Garnet F1	Blocky red; highly resistant L4	L4, IR: TSWV 0
Zamboni	Large very uniform fruits	Tm2

Yellow Bell Pepper

Variety	Key Notes	Disease Resistance
Berkeley F1	Blocky yellow; avg 225–245g	Tm 0–3
Bachata F1	Strong balanced plant; generative steer	Tm 0–3

Orange Bell Pepper

Variety	Key Notes	Disease Resistance
Milena F1	Early maturing orange blocky	HR: PVY 0–1, Tm 0–3; IR: TSWV 0
Orangery F1	High yield; good quality fruits	Tm 0–3

Mini Pepper

Variety	Color	Key Notes	Disease Resistance
Lunchbox Red	Red	Sweet; selected for snacks/clamshells	—
Trirosso F1	Red	Sweet; self-pollinating	Tm 2

Pepper Rootstock

Variety	Key Notes	Disease Resistance
Foundation F1 (RZ 52-03)	Strong root system; nematode resistant	Tm 0, Nematode
Bedrock F1 (RZ 52-04)	Generative effect on graft; nematode resistant	Tm 3, Nematode, IR: Phytophthora, TSWV

Mini Pepper Varieties

Mini peppers (typically 40–70g fruit weight) have grown significantly in market share due to their snacking convenience, sweetness, and visual appeal in mixed-color retail packs. Key considerations for mini pepper production:

• Higher fruit count per plant than standard block types
• Shorter days to first harvest
• Typically harvested at the immature green stage or allowed to color for premium pricing
• Require careful grading for size uniformity in retail pack formats
• Well suited to high-wire long-season production systems

Browse our Greenhouse Pepper varieties including block and mini types.

Propagation and Transplanting

Seeding and Germination

• Sow into 128 or 200-cell plug trays using a fine-textured germination mix
• Germination temperature: 25–28°C (77–82°F)
• Days to germination: 7–10 days
• Pelleted seed is strongly recommended for precision seeding and uniform germination
• Maintain high humidity during germination; reduce after emergence to prevent damping-off

Propagation Period

• Total propagation time from seeding to transplant: 8–10 weeks
• Grow-on temperature: 20–22°C day / 18–20°C night
• Transplant at the 6–8 true leaf stage, before flower buds are visible, to avoid transplant shock affecting early fruit set
• Harden plants gradually before transplanting into the production greenhouse

Transplanting

• Plant spacing: 2.5–3.0 plants/m² for standard block types; 3.0–3.5 plants/m² for mini peppers
• Row configuration: typically double rows on raised substrate slabs (rockwool, coco coir, or perlite)
• Transplant into pre-wetted substrate; avoid planting too deep
• Maintain substrate temperature above 18°C at transplanting to encourage rapid root establishment

Plant Training and Pruning

Initial Training

Pepper plants naturally fork at the first flower (the crown bud). The standard training system for greenhouse peppers involves:

1. Crown bud removal — remove the first flower at the fork to direct energy into vegetative growth and establish a strong plant framework
2. Two-stem training — allow two main stems to develop from the first fork; tie each stem to a separate support string
3. Subsequent branching — at each subsequent fork, retain one stem and remove the other (or allow both in high-density systems)

Ongoing Pruning

• Remove all shoots below the first fork to maintain an open, well-ventilated plant base
• Remove leaves showing disease symptoms immediately
• Leaf pruning in the lower canopy improves airflow and reduces Botrytis pressure — remove lower leaves progressively as the crop develops
• For mini peppers, a higher stem density is often maintained to maximize fruit count per m²

High-Wire Production

Long-season greenhouse pepper production uses a high-wire system where plants are trained vertically and lowered progressively as they grow, similar to tomato production. This allows continuous production from a single planting for 9–12 months or longer.

Climate Management

Temperature

• Day temperature: 22–26°C (72–79°F) during fruit development; reduce to 20–22°C during coloring
• Night temperature: 18–20°C (64–68°F)
• Minimum temperature: Do not allow temperatures below 15°C — chilling causes fruit deformation and blossom drop
• Maximum temperature: Above 32°C, pollen viability drops sharply and fruit set fails. Ventilate aggressively and use shade screens in summer.
• DIF (day-night temperature difference): A positive DIF (warmer days than nights) promotes compact, sturdy growth

Humidity and VPD

• Target relative humidity: 65–75%
• Target VPD: 0.8–1.2 kPa during the day
• High humidity (>85%) promotes Botrytis and powdery mildew; low humidity (<50%) causes blossom drop and tip burn
• Maintain horizontal airflow fans throughout the crop to prevent humidity stratification

CO₂ Enrichment

• Target CO₂: 800–1,000 ppm during daylight hours with vents closed
• CO₂ enrichment significantly improves fruit set, fruit size, and yield in closed or semi-closed greenhouse systems
• Reduce or stop enrichment when vents are open to avoid waste

Light

• Optimal DLI: 25–30 mol/m²/day
• Supplemental lighting is beneficial in winter production at northern latitudes
• Maximum photoperiod: 16–18 hours — some varieties are photoperiod-sensitive; confirm before setting lighting schedules

Irrigation and Nutrition

Irrigation

• Drip irrigation directly to the substrate slab is standard in soilless greenhouse pepper production
• Irrigation frequency and volume are managed based on radiation sum (typically 100–150 J/cm² per irrigation event)
• Maintain substrate water content at 60–80% field capacity; avoid waterlogging which promotes Phytophthora
• First irrigation of the day: 1–2 hours after sunrise; last irrigation: 1–2 hours before sunset
• Target drain percentage: 20–30% to prevent salt accumulation in the substrate

Nutrition

Pepper has moderate to high nutrient requirements. Key parameters for a standard pepper nutrient solution:

• EC (electrical conductivity): 2.5–3.5 mS/cm in the root zone; higher EC improves fruit quality and shelf life but reduces yield
• pH: 5.5–6.0 in the root zone
• Key macronutrients: Nitrogen (NO₃⁻ dominant), Potassium (high K:N ratio during fruiting), Calcium (critical for cell wall integrity and blossom end rot prevention), Magnesium
• Key micronutrients: Iron, Manganese, Zinc, Boron (important for pollen viability and fruit set)
• Increase K and Ca during heavy fruiting periods; reduce N to avoid excessive vegetative growth

Pollination

Pepper flowers are self-fertile but require vibration to release pollen effectively. In greenhouse production, pollination is typically achieved by:

• Bumblebees (Bombus terrestris) — the most effective and widely used pollination method in commercial greenhouse pepper production. Bumblebee hives are introduced at first flower and replaced every 6–8 weeks.
• Electric vibrators (pollination wands) — used to manually vibrate flower clusters; labor-intensive but effective in smaller operations or when bees are unavailable
• Air movement — horizontal airflow fans contribute to passive pollen dispersal but are insufficient as the sole pollination method

Poor pollination is one of the most common causes of misshapen fruit, blossom drop, and low fruit set in greenhouse peppers. Ensure bumblebee hives are active and healthy throughout the production season.

Fruit Development and Coloring

Pepper fruit development follows a predictable timeline from fruit set to harvest:

• Days from fruit set to green harvest: 45–60 days depending on temperature and variety
• Days from green to full color (red/yellow/orange): an additional 3–4 weeks
• Mini peppers: reach harvest size faster — typically 35–45 days from fruit set to green harvest

Coloring is temperature-sensitive. Optimal coloring temperature is 18–22°C — high temperatures (>28°C) slow or prevent color development. In summer production, night cooling or shade management may be needed to achieve full color.

Harvest

Harvest Timing

• Harvest standard block peppers at full color (red, yellow, or orange) for maximum market value
• Green harvest is possible for specific markets but commands lower prices
• Mini peppers are harvested at full size — either green or at full color depending on market specification
• Harvest frequency: 2–3 times per week in peak production

Harvest Technique

• Cut fruit with a clean, sharp knife or scissors — do not pull, which can damage the plant and create entry points for disease
• Leave a short stem (1–2cm) attached to the fruit to extend shelf life
• Handle fruit carefully to avoid bruising — pepper skin is thin and bruises easily
• Harvest into clean, ventilated containers; avoid stacking more than 2–3 layers deep

Post-Harvest Handling

• Cool fruit to 8–10°C as quickly as possible after harvest
• Do not store below 7°C — chilling injury causes surface pitting and accelerated decay
• Target storage humidity: 90–95%
• Shelf life at optimal storage: 2–3 weeks for standard block types; 1–2 weeks for mini peppers

Common Production Challenges

• Blossom drop — caused by temperature extremes, low humidity, poor pollination, or excessive nitrogen. Review climate and pollination management.
• Misshapen fruit — typically caused by poor pollination or boron deficiency. Ensure bumblebee activity and check boron levels in the nutrient solution.
• Blossom end rot — calcium deficiency at the fruit tip; caused by irregular irrigation, high EC, or poor calcium uptake. Maintain consistent irrigation and adequate calcium supply.
• Sunscald — white or bleached patches on fruit exposed to direct intense light. Use shade screens in summer and maintain adequate leaf cover over developing fruit.
• Phytophthora root rot — avoid waterlogging; select resistant varieties; maintain substrate hygiene between crops.

Browse our full range of Greenhouse Pepper varieties — including standard block, lamuyo, and mini pepper types with strong disease resistance packages.

The Bottom Line

Greenhouse sweet pepper production rewards attention to detail at every stage — from variety selection and propagation through climate management, nutrition, and harvest. Mini peppers add a high-value, fast-cycling option to any pepper program, with strong retail demand and efficient use of greenhouse space.

Have questions about variety selection, production systems, or crop management for your greenhouse pepper program? Contact the Paramount Seeds team — we're here to help.