Our tromboncino squash (Cucurbita moschata ‘Tromboncino’) have been causing a real stir this summer in the Walled Garden and Courtyard area near the Gift Shop. This giant, climbing squash is spectacular at this time of year, producing long trumpet-shaped fruits that can grow up to 1m long (!) if left on the plant to mature.
Like all squashes it makes a vigorous plant. Tromboncinos like to climb, and produce lots of side shoots as well, so are ideal for covering a wall with support or a trellis. Trailing them over an archway has the advantage of allowing the fruits to hang down unhindered as they grow, resulting in a really long and straight crop of fruits.
They like as much sun and shelter as possible, and prefer to grow in a free draining soil that is watered regularly. It takes a lot of energy to produce such a huge fruit, so you should feed your tromboncino regularly. Organic matter is the best – try mulching with manure like you would roses or rhubarb.
Mulching with organic matter has the added advantage – along with regular, consistent irrigation – of helping to stave off the onset of mildew. Most Cucurbita suffer with powdery mildew on their large leaves, although the tromboncino is more resistant than most. Powdery mildew proliferates in hot and dry conditions so keeping the soil around your plants evenly moist will help.
Tromboncinos work well in large containers too. Vertical gardening using containers is a great way to maximise space in a small garden. Consider covering unsightly walls and fences and situating containers to make the most of a south-facing aspect.
As tromboncinos are such big and hungry plants, you’ll need to use a really big container. You could even try recycling unwanted household items like an old dustbin or a laundry basket, but don’t forget to drill plenty of drainage holes in the bottom so your squash doesn’t drown when you water it.
To really maximise space, tromboncinos can be grown in combination with other climbing crops that can share the same trellis or other support. Runner beans make good bedfellows as do nasturtiums which will climb as well as scramble given the chance. Their peppery flowers and leaves are edible but also highly ornamental and look great paired with a tromboncino’s large palmate leaves and blousy yellow flowers, creating a tropical-looking effect.
The fruits themselves are extremely versatile; they can be fried, grilled, roasted or simply eaten raw. If used in salads they are best picked when they are young and small and used much like you would a courgette or cucumber. They are sweet and nutty and perfect for shredding like a vegetable spaghetti.
The more you pick the heavier your tromboncino will crop. It is great fun though to leave some and see just how big they’ll grow. They bigger fruits should be left for the skins to go hard and can be treated like you would a winter squash.
The only danger is that your tromboncino will grow so big and heavy that it will break and pull itself off the plant. In this instance a pair of tights wrapped around the fruit and tied to an additional support is perfect for taking some of the weight at the same time as being stretchy enough to allow the fruit to continue to grow.
Whether you’re growing tromboncino squash for edible, ornamental or novelty value they are a brilliantly versatile, easy to grow plant – and loads of fun too!