Peppers and chilli – from sweet to the hottest

Peppers and Chilli – from Sweet to the Hottest

Peppers (Capsicum spp.) are among the most diverse crops you can grow in your garden. From sweet, fleshy bell peppers through moderately hot jalapeños to fiery habaneros or the legendary Carolina Reaper – all belong to the genus Capsicum and all can be successfully grown in Czech conditions. The key is timely sowing, proper temperature, and patience.

1. Types of Peppers – from Sweet to Extremely Hot

Sweet Peppers (Capsicum annuum)

The most widespread type in Czech cuisine. No heat (0 SHU). Large, fleshy fruits are ideal for direct consumption, stuffing, or grilling. Typical varieties: Yolo Wonder, California Wonder, Anka, Slavy, Granova.

Bell peppers form a separate group of sweet peppers – elongated fruits with distinctly thick walls excel when grilling, roasting, and preserving. Popular varieties: Karmen, Corno di Toro.

Mildly Hot Peppers (100–8,000 SHU)

Pleasant bite without uncomfortable pain. Suitable for sauces, marinades, and everyday cooking.

• Pimientos de Padrón (500–2,500 SHU) – Spanish classic where most fruits remain sweet but some provide pleasant surprise
• Jalapeño (2,500–8,000 SHU) – world's most common chilli, meaty fruits with universal use
• Hungarian Hot Wax (1,000–5,000 SHU) – Czech-Hungarian classic, yellowish-green, excellent for pickling

Moderately Hot Chilli (10,000–100,000 SHU)

This is where more pronounced heat begins. For most people, it represents the upper limit of the comfort zone.

• Serrano (10,000–25,000 SHU) – Mexican variety with thin walls, essential for salsa
• Cayenne (30,000–50,000 SHU) – thin-walled classic intended primarily for drying and grinding
• Tabasco (30,000–50,000 SHU) – small fruits, famous for the eponymous sauce
• Piri Piri (50,000–100,000 SHU) – African-Portuguese variety with distinctive aroma

Very Hot Chilli (100,000–600,000 SHU)

For adventurous cooks. Gloves recommended when handling.

• Habanero (100,000–350,000 SHU) – iconic variety with tropical fruity aroma
• Scotch Bonnet (100,000–350,000 SHU) – Caribbean habanero relative, popular in Jamaican cuisine
• Fatalii (125,000–400,000 SHU) – African variety with distinctive citrus flavor

Extremely Hot – Superhot (600,000–3,000,000+ SHU)

Exclusively for experienced growers and chilli enthusiasts. Handling requires protective equipment – gloves, possibly eye protection.

• Bhut Jolokia (Ghost Pepper) (855,000–1,041,427 SHU) – first variety exceeding one million SHU
• Trinidad Moruga Scorpion (1,200,000–2,009,231 SHU)
• Carolina Reaper (1,400,000–2,200,000 SHU) – long-standing Guinness World Record holder
• Pepper X (2,693,000 SHU) – current world record holder (since 2023)

Scoville Scale – Heat Overview

What is SHU? Scoville Heat Units express the concentration of capsaicin – an alkaloid responsible for heat. A value of 0 means no heat, while 2,000,000+ is near the physiological tolerance limit for most people.

2. Sowing and Pre-growing – Start Early

Peppers and chilli have the longest growing season of all commonly grown vegetables – from sowing to harvest of fully colored fruits takes 120–180 days, with superhot varieties even longer. Early sowing is therefore absolutely essential for success.

When to Sow

Sowing Procedure

1. Seed Soaking: Unlike tomatoes, pepper seeds germinate much more slowly. Soaking in warm water (25–30 °C) for 12–24 hours significantly speeds up germination. For superhot varieties, add chamomile tea to the water – it helps suppress potential surface pathogens.

2. Substrate: Use fine seed-starting mix, slightly pre-moistened. Spread seeds evenly on the surface and cover with a thin layer of substrate (3–5 mm). Deeper placement slows germination.

3. Germination Temperature: 25–30 °C – this is a crucial difference from tomatoes. Peppers germinate very slowly or not at all below 20 °C. A heat mat is practically indispensable for chilli.

4. Germination Time:

5. Sweet peppers: 7–14 days
6. Jalapeño, Cayenne: 10–20 days
7. Habanero: 14–30 days

8. Superhot: 14–40 days (occasionally longer – don't discard substrate prematurely)

9. Covering: Cover the container with clear film or lid to maintain moisture and heat. Once first seedlings germinate, uncover immediately – otherwise risk of stretching and mold.

Supplemental Lighting as Success Foundation

Sowing in January and February means seedlings grow during the shortest days of the year – natural light from the window is insufficient in both intensity and duration. The result is stretched, mechanically weak seedlings prone to disease.

Solution: supplemental lighting. LED grow lights are practically indispensable for chilli sown before March. An LED panel or T5/T8 fluorescent fixture placed 10–20 cm above seedlings, running 14–16 hours daily, is sufficient. A light timer reliably automates the light cycle.

Without supplemental lighting, seedlings survive but will be weaker, slower, and more disease-prone. For superhot varieties with their extremely long growing season, this handicap can mean the difference between harvest and failure.

3. Pricking Out and Transplanting

Pricking Out

Prick out after the first pair of true leaves forms, usually 3–5 weeks after sowing. Unlike tomatoes, don't plant peppers deeper than they were growing – their stems don't produce adventitious roots, so deeper planting provides no benefit. Transplant into 8–10 cm pots with drainage holes.

Transplanting to Garden or Containers

Timing: Only after the last frost (mid-May), ideally late May. Soil temperature must reach at least 15 °C – peppers are even more sensitive to spring cold than tomatoes. Neglecting this rule leads to stagnation and leaf yellowing.

Spacing: 40–50 cm in rows, 50–60 cm between rows.

Location: The hottest and sunniest spot in the garden. Ideally against a south-facing wall where heat accumulates, or in a greenhouse. Peppers require warmth and cannot tolerate drafts or shade.

4. Pepper and Chilli Care

Watering

Peppers need regular but moderate watering. The root system is shallower than tomatoes, so surface soil drying is critical. Mulching under plants significantly reduces evaporation and helps maintain even moisture.

• Water with appropriately warm water directly at the soil – cold hose water causes root stress.
• On hot days, water in early morning or evening, not midday.
• Irregular watering is one of the most common causes of flower and fruit drop, plus fruit deformities.

Fertilizing

Peppers are moderately demanding. Over-fertilizing with nitrogen promotes lush foliage at the expense of fruit setting.

• Before planting: Work ripe compost into the soil.
• During growth: Balanced fertilizer with N-P-K ratio approximately 1:1:1 every 2–3 weeks.
• During fruiting: Switch to fertilizer with higher potassium content – so-called tomato fertilizer.
• Chilli in containers: Liquid fertilizer once weekly at half strength; limited substrate volume depletes nutrients quickly.

Shaping

Sweet peppers don't require shaping. For chilli, two interventions work well:

• Top pruning: When the plant has 8–10 leaves, shorten the main stem. The plant will branch, produce more fruiting branches, and overall yield will be more abundant. For superhot varieties, this step is especially recommended.
• Removing crown flower: Remove the first flower in the stem fork. The plant will invest energy in vegetative growth, and later harvest will be more numerous and even.

Temperature

Peppers and chilli are exceptionally heat-loving among vegetables:

• Optimal temperature for growth and fruiting: 22–28 °C
• Below 15 °C plants practically stagnate
• Below 10 °C cold stress occurs with leaf yellowing
• Above 35 °C flowers drop, especially in hot varieties
• Night temperature shouldn't fall below 15 °C long-term

5. Diseases and Pests

Most Common Problems

Flower Drop: Most often caused by temperature stress (cold or excessive heat), irregular watering, or over-fertilizing with nitrogen.

Aphids: Very common, especially on young seedlings and in greenhouses. Effective solutions include soap solution, nettle extract, or biological preparations with natural insecticides.

Spider Mites (Thrips): Tiny mites on leaf undersides cause silvery or bronze leaf surface appearance. They thrive in dry, warm environments, typically in greenhouses. Increased humidity and targeted spraying quickly resolve the issue.

Fruit Rot: Caused by fungal pathogens in excess moisture. Don't water over leaves or fruits; ensure adequate air circulation through the canopy.

Slugs: Danger primarily threatens freshly transplanted seedlings. Protective rings of fine wood ash, mulch, or beer traps reliably prevent problems.

6. Harvest

When to Harvest

Sweet Peppers can be harvested green at technical ripeness or fully colored. Ripe fruits are noticeably sweeter, more aromatic, and contain significantly more vitamins – especially vitamin C. You'll recognize ripeness by full color and slightly yielding flesh to gentle squeeze.

Chilli harvest at full color ripeness – capsaicin heat reaches maximum precisely then. Always cut fruits with scissors or pruning shears; pulling damages fragile branches and can break entire fruiting branches.

Continuous Harvest as Fruiting Stimulus

Regular harvest of ripe fruits naturally stimulates the plant to produce more flowers. Overripe and forgotten fruits do the opposite – the plant interprets this as having fulfilled its reproductive role.

7. Drying and Processing Chilli

Drying

Air Drying: Thread fruits on strong twine and hang in a ventilated, dry, shaded space. Suitable for thin-walled varieties (Cayenne, Thai, Piri Piri). Expect 2–4 weeks depending on wall thickness and air humidity.

Food Dehydrator: 55–65 °C for 8–16 hours depending on fruit size and thickness. Most reliable and uniform method with predictable results.

Oven Drying: 60–70 °C with slightly open oven door for steam release, 6–12 hours. Less uniform but readily available solution.

Grinding

Perfectly dried fruits, grind in a spice grinder or powerful blender. Watch out for capsaicin vapors – grind exclusively in well-ventilated space, preferably with a mask. Cayenne, Piri Piri, and Bird's Eye are ideal for homemade chilli powder due to their thin walls and intense flavor.

Fermentation (Hot Sauce)

1. Chop chilli, add 2–3% salt by total weight, and mix thoroughly.
2. Transfer to a jar and let ferment for 1–4 weeks at room temperature. Open lid slightly daily to release CO₂.
3. Blend the fermented mixture, strain, and season with vinegar.
4. Result is a living hot sauce full of probiotics, enzyme-rich, with complex flavor.

Other Processing Methods

• Vinegar Pickling: Proven for Jalapeño and Hungarian Hot Wax.
• Chilli Oil: Infuse dried fruits in quality olive oil for 2–4 weeks in a dark place.
• Freezing: Fresh chilli freezes without blanching – it softens slightly after thawing but heat and aroma remain intact.
• Smoking (Chipotle): Smoked jalapeños are a delicacy with deep smoky flavor. Requires a smoker and extended smoking at low temperature.

8. Recommended Varieties for Czech Conditions

Sweet Peppers

Mild and Moderate Chilli

Hot and Superhot

9. Indoor Chilli Growing and Overwintering

Chilli are essentially perennial tropical plants – in their natural environment they grow and fruit for several years. In Czech conditions, you can successfully overwinter them and achieve significantly more abundant harvest in the second season:

1. Before first frosts (October) move the plant indoors before temperatures drop below 10 °C.
2. Prune the plant to approximately one-third its height. Remove all remaining fruits and most leaves – the plant will enter vegetative dormancy.
3. Place in a cool but bright location with temperature 10–15 °C. Water minimally – just enough so the root ball doesn't completely dry out.
4. In spring (February–March) move to warmth, apply balanced fertilizer, and the plant will quickly regrow. Overwintered specimens are several weeks ahead of seedlings.
5. Overwintered plants fruit earlier and more abundantly than in their first season – for superhot varieties, overwintering is especially advantageous.

For year-round indoor chilli growing, LED grow lights are essential. Plants require minimum 12–14 hours of quality light daily; without it they stagnate and don't fruit.

10. Frequently Asked Questions (FAQ)

Why aren't my peppers growing?
The most common reason is cold – peppers practically stagnate below 15 °C regardless of watering or fertilizing. Another frequent cause is persistently waterlogged substrate or inadequate drainage from containers.

Why do flowers drop?
Temperature stress (below 15 °C or above 35 °C), insufficient pollination (for indoor plants, transfer pollen between flowers with a soft brush) or excess nitrogen in fertilizer.

Can I grow sweet peppers next to chilli?
For current season consumption, yes – the fruit carries the genetic makeup of the mother plant and cross-pollination doesn't affect taste or heat. If you plan to collect seeds for next year, crosses mean offspring won't match the mother variety.

How can I naturally increase chilli heat?
Mild, controlled stress increases capsaicin production: occasional drying (not complete drying!), full sun, higher temperatures, and harvesting at full color ripeness.

How many fruits will I harvest from one plant?
Jalapeño: 20–40 fruits. Habanero: 30–80 fruits. Carolina Reaper: 20–50 fruits (smaller in size but extraordinarily intense). Sweet bell pepper: 6–15 large fruits.

Is capsaicin dangerous to health?
In common amounts, no – quite the opposite, it has proven anti-inflammatory and metabolically stimulating effects. When handling superhot varieties, always wear latex or nitrile gloves and don't touch your face. For excessive consumption heat, milk (casein binds capsaicin) helps, not water.

When should I sow to harvest in August?
Sweet peppers: February. Jalapeño and Cayenne: late January. Habanero: mid-January. Superhot varieties: early January. In all cases, plan for supplemental lighting.

11. Growing Calendar – Peppers and Chilli in Czech Republic

Summary

Peppers and chilli are rewarding crops that will abundantly repay any grower who provides them with adequate warmth and time. Start sowing early (January–February), ensure supplemental lighting for robust seedlings, and after the last frost plant in the warmest garden spot or in a greenhouse. Quality seedlings and regular fertilizing form the foundation of a productive season. And once chilli fever catches you – the world of superhot varieties offers endless adventure for both palate and grower's soul.