Jalapeno
The chilli everyone recognises, and a fair choice here because you pick it green anyway, so the Irish season never has to ripen it.
The jalapeno is the chilli most people have actually eaten, and the one that turns up sliced on everything from nachos to pizza. It is a medium heat, thick walled, blunt ended fruit about 6 to 8cm long, harvested green in almost all culinary use. That last detail matters in Ireland, because a variety you pick green is a variety that does not need the extra weeks of autumn heat our climate cannot supply. Look for the selection sold as Early Jalapeno if you can, since it crops noticeably sooner.
Quick facts
- Botanical name
- Capsicum annuum
- Type
- Open pollinated
- Category
- Medium heat, thick walled
- Difficulty
- Challenging
- Hardiness
- Tender, no frost tolerance
- In Ireland
- Needs a greenhouse or tunnel
- Germination
- 7 to 21 days at 25 to 30C
- Sowing depth
- 5mm
- Spacing
- 45cm apart, 50cm between rows
- Height
- 75cm
- Position
- Full sun
- Containers
- Grows well in pots
- Sowing to harvest
- 18 to 26 weeks
- Harvest
- August to October
Sowing and harvest calendar for Jalapeno
Months shaded below are the reliable windows for Irish conditions.
Where to buy Jalapeno chilli seeds in Ireland
Irish suppliers that stock this, so postage stays domestic and seed arrives in time to sow. These are plain links, not paid placements.
Order online
- Quickcrop Irish Sowing and harvest months on every listing Ballymote based, lists sowing and harvest months per product and ships across Ireland. Visit Quickcrop , Co. Sligo
- Seedaholic Irish Detailed packet notes, posted from Co. Galway Family run in Clonbur since 2005, deep heirloom range with detailed growing notes on every packet. Visit Seedaholic , Co. Galway
Garden centres and mixed retailers
- Mr Middleton Irish Familiar named varieties, posted from Dublin Mail order arm of a long established Mary Street shop, carries the familiar named varieties the organic specialists skip. Visit Mr Middleton , Co. Dublin
- Johnstown Garden Centre Irish Widest branded range, best ordered early in the year Third generation family business near Naas with the widest branded range, though popular varieties sell out by midsummer. Visit Johnstown Garden Centre , Co. Kildare
Why it suits Ireland
The case for a jalapeno here is that its normal harvest stage is green. You are not waiting for a red fruit at the end of October, you are cutting firm green ones from late July, which fits an Irish season much better than a variety that must ripen fully to be worth eating.
Against that, it is a bigger, later plant than Apache or Hungarian Hot Wax and it wants a proper greenhouse or polytunnel rather than a windowsill. It also sets less willingly in cool nights than the wax types, so it repays being kept warm in early summer.
If you can find seed sold as Early Jalapeno, take it. The gain of two or three weeks matters more here than it does in a warmer country.
Growing notes
Sow January to March with bottom heat at 25 to 30C, and use a grow light for anything sown before the end of February.
Pot on into a 10 litre pot or a greenhouse border at 45 to 50cm spacing. Plants reach around 75cm and carry heavy fruit, so stake them.
Pinch out the growing tip at 20cm to encourage branching. Feed with high potash tomato feed once the first fruit set, and water evenly rather than heavily, since a plant that swings between dry and soaked drops flowers.
Pick green from late July, once the fruit are full sized, firm and glossy, cutting rather than pulling. Regular picking keeps the plant setting new fruit; a plant carrying a full load of maturing fruit stops flowering.
Thick walled chillies dry badly in Irish air, so do not try to string these up. They freeze whole extremely well and keep their heat, and they pickle beautifully, which is what most of a jalapeno crop should become.
Common questions
How hot is a jalapeno?
Usually given as 2,500 to 8,000 Scoville units, which is medium: hot enough to notice clearly, mild enough to eat several. It sits well below a cayenne and far below anything in the habanero class. Heat varies with growing conditions as it does with every chilli, and fruit that have been left to ripen red are hotter and sweeter than the same fruit picked green.
What are the brown lines on my jalapenos?
Those are corking, fine tan or brown striations in the skin, and they are a sign of maturity rather than a disease. In Mexico corked fruit are considered a mark of a properly developed jalapeno and are preferred. They are perfectly good to eat. Do not confuse corking, which is a shallow surface pattern, with sunken soft patches, which are rot.
Why does my jalapeno plant not fruit well in a greenhouse?
Most often cool nights during flowering. Jalapenos set poorly when nights drop below about 15C, which is normal in an Irish greenhouse until well into summer. Close the greenhouse in the evening, keep young plants under fleece on cold nights in May and June, and tap the flowers daily on still days to move the pollen. A plant on a warm indoor windowsill often sets better than one in a cold greenhouse for exactly this reason.
More chillies to consider
Apache F1
AGMF1 hybrid / Compact hot chilli
The best chilli for a windowsill or a small greenhouse: knee high, heavy cropping, and genuinely hot despite the size.
Growing notes and stockistsHungarian Hot Wax
AGMOpen pollinated / Early wax type, mild to medium heat
The most forgiving chilli for a cool Irish greenhouse: early, mild, and perfectly usable at the pale yellow stage before it ever turns red.
Growing notes and stockistsPadron
Open pollinated / Small green frying pepper
Arguably the smartest chilli choice for an Irish season, because you harvest it small and green and never wait for it to ripen.
Growing notes and stockistsCayenne
Open pollinated / Long thin drying chilli, hot
The one to grow if you want your own dried chilli flakes, but it needs a January sowing and a warm greenhouse to finish properly.
Growing notes and stockists