This page is for a basic understanding of growing chilli plants in different growing conditions
Seed Germination
Chilli seeds require warmth and humidity to germinate quickly and successfully.
Use a heated propagator to provide consistent bottom heat and a high-humidity enclosure for optimal results. Natural germination (without added heat or humidity) can result in lower success rates and slower germination times.
Growing Indoors - Windowsill
Advantages:
- Protection from frost, heavy rain, and high winds
- Reduced risk of insect infestations
- Longer growing season, leading to better pod production
Disadvantages:
- Lack of all-day sunlight
- Flower drop-off due to imbalance in the climate - See our VPD Page
- Limited pot size and height restrictions, particularly on windowsills
- Smaller plant sizes
There is nothing wrong with growing on the windowsill if this is your only place to grow, choose your plants based on what climate you can provide, smaller plants and pot sizes still guarantee success if you follow our advise
Growing Outdoors – Open Ground
Advantages:
In the UK climate, growing chilli plants in open ground offers no significant advantages. If we had guaranteed 5 months of sunny warm days with a gentle breeze with some rain then its not a problem, 40 years I have only ever seen that kind of summer a few times
Disadvantages:
Severe weather requires plants to harden off, delaying growth
Repeated bad weather can waterlog soil and slow plant development
The UK summer is too short and unreliable for consistent results
Growing Outdoors – Greenhouse/Tunnel
Advantages:
- Protection from high wind and rain
- Stable growing environment minimizes the need for hardening off
- Stable humidity levels encourage good flower production
- Extended growing season
- Improved pod production with better flavour and heat
Disadvantages:
- Ideal environment for insects, increasing the risk of infestations
- Growing season remains limited, starting after the last spring frost and ending with the first autumn frost
The most basic green type of poly tunnels work very well, cheap and effective, a rare combination these days, if you have space for these then it is recommended to use them or similar for better growth and pod production on all chilli plant types
Plant Types
Some chilli varieties adapt well to different growing conditions, while others are more climate-dependent.
Established Varieties: Jalapeño, Cayenne, Aji and other common varieties have strong, adaptable genetics, allowing them to thrive in various environments.
Super-Hot Varieties: Super-hot chillies evolved over hundreds of years in stable climates (e.g., the Caribbean) and struggle in the UK's unpredictable weather. Unstable growing conditions reduce pod production and chilli heat levels.
Wild Chillies: These plants face similar challenges when grown outside their natural environments.
Plant Pot Sizes
See our Page on Pot sizes here for full information on this
Depending on how long the season is available to you the bigger you can go on the pot size, start with a 7/9cm starter, pot up to a 2-5 Litre, then 5-10 Litre, for the longest time available 10-20 litre
It is very possible to grow chilli plants and get some pods in a 9cm pot, it will no be very big and produce the smallest number of pods, but is the quickest grow time available, if time is short, go small on the pots
Top Tip for Beginners
Start with well-established chilli varieties like Jalapeño or Cayenne or Aji. Once you've gained experience, you can explore more exotic and sensitive chilli plants.