Tromboncino
For growers with a tunnel or a warm sheltered wall. Climbs out of slug reach and shrugs off mildew, but it needs a long season.
Tromboncino, also sold as Trombetta d'Albenga, is a Ligurian heirloom that behaves nothing like an ordinary courgette. It is a rampant climbing vine rather than a bush, the fruit are long pale green curved necks that can reach a metre if you let them, and the flesh is dense and nutty instead of watery. It is also a different species from ordinary courgettes, Cucurbita moschata rather than C. pepo, which is where several of its advantages come from.
Quick facts
- Botanical name
- Cucurbita pepo
- Type
- Heirloom
- Category
- Climbing, pale green
- Difficulty
- Easy, good first crop
- Hardiness
- Tender, no frost tolerance
- In Ireland
- Cloche or fleece helps
- Germination
- 5 to 10 days at 18 to 25C
- Sowing depth
- 2cm
- Spacing
- 90cm apart, 120cm between rows
- Height
- 2.5m
- Position
- Full sun
- Containers
- Grows well in pots
- Sowing to harvest
- 10 to 14 weeks
- Harvest
- August to September
Sowing and harvest calendar for Tromboncino
Months shaded below are the reliable windows for Irish conditions.
Where to buy Tromboncino courgette 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
- Seedaholic Irish Heirloom specialist, the most likely Irish source for unusual squash Family run in Clonbur since 2005, deep heirloom range with detailed growing notes on every packet. Visit Seedaholic , Co. Galway
- Brown Envelope Seeds Irish Organic seed grown and saved in West Cork Grows and saves its own certified organic seed in West Cork, so the varieties are already adapted to Irish conditions. Visit Brown Envelope Seeds , Co. Cork
Why it suits Ireland
Two of its traits are worth real money in an Irish garden. First, it climbs, so the fruit hang in the air rather than resting on cold wet soil, which is where slugs and rots find ordinary courgettes. Second, being Cucurbita moschata rather than C. pepo, it generally holds off powdery mildew for weeks after the bush courgettes beside it have gone grey and brittle.
The catch is heat. C. moschata is the warmer-climate branch of the squash family and Tromboncino is genuinely later to start than a bush courgette. Outdoors in a cool exposed garden you may get a magnificent vine and a modest crop. Under a tunnel, or on a sunny sheltered wall in the south or east, it is excellent.
Wind is the other consideration. A mature vine carries a great deal of wet leaf, and it needs a support built to hold it. Growing it up a polytunnel frame or against a wall solves the wind problem and the heat problem together.
Growing notes
Sow one seed on edge in a 9cm pot in late April, at 18 to 25C, and treat it exactly as you would any courgette until planting out. Give it a little longer in the pot than a bush type, since it should not go out until early June.
Plant one to a strong support with at least 1.5m of clear ground around it, and tie the leading shoot in until it takes hold. It has tendrils but the weight of the vine outpaces them.
Pick the fruit young, at 20 to 30cm, when it is still tender and the skin can be scratched with a thumbnail. At that stage it is a courgette, only better. Left on the vine it will keep extending and curling, and while a metre-long fruit is a good photograph it makes for coarse eating and it stops the plant setting anything else.
Common questions
Will Tromboncino ripen outdoors in Ireland?
It will crop outdoors as a courgette in a warm sheltered garden in a decent summer, but it is later than a bush courgette and it wants more heat, so in a cool or exposed site it can spend all of July making vine and very little fruit. A polytunnel or a south facing wall makes it far more dependable. If you want it to mature into a winter squash rather than be picked young, that is a genuine stretch in most of Ireland and only worth attempting under cover.
Why is it seedless?
Not entirely, but nearly. All the seed sits in the bulb at the blossom end, so the long curved neck is solid flesh with nothing to scoop out. That is why it is worth growing for the kitchen: you get far more usable flesh per fruit than from a normal courgette, and the texture stays firm instead of collapsing.
Can I save seed from Tromboncino, and will it cross with my other courgettes?
You can, since it is open pollinated. Usefully, it is Cucurbita moschata, so it will not cross with ordinary courgettes, summer squash or most pumpkins, which are Cucurbita pepo. It will cross with butternut squash and other C. moschata types. To save seed you have to let a fruit ripen fully to a hard tan skin on the vine, which takes a long warm season and in Ireland realistically means a tunnel.
Does it really need support?
It needs either a strong support or a lot of ground. Left flat it will run four or five metres and root as it goes, and the fruit lying on wet Irish soil are slug bait. Trained up a fence, a tunnel hoop or a serious frame, the fruit hang clear and curl into their characteristic shape. Whatever you build has to hold a heavy wet vine in an August gale, so it needs to be a good deal stronger than a bean wigwam.
More courgettes to consider
Defender F1
AGMF1 hybrid / Green, bush
The safe choice. Early, heavy and virus resistant, which matters more here than flavour ever will.
Growing notes and stockistsSoleil F1
F1 hybrid / Yellow, bush
Grow one yellow alongside a green one. Easy to spot among the leaves, which means fewer accidental marrows.
Growing notes and stockistsBlack Beauty
Heirloom / Green, bush
Cheap, widely sold and open pollinated, so you can save your own seed. Slightly later than the hybrids.
Growing notes and stockists