Every year I grow at least a few things that are just for fun and not very practical. And by ‘not very practical’ I mean that they are neither edible or very attractive! It turns out that a few of the more unusual edibles this year have dropped into this category because they have not been very tasty – such as the strawberry spinach. But one little curiosity has done exactly what I expected and provided a bit of fun.

Cyclanthera explodens, doing what it does best – going mad!

I have grown Cyclanthera explodens before but I first met it when I was a student at Kew Gardens where it was grown in the Order Beds along with other cucurbits. Commonly known as exploding cucumber it must not be confused with the squirting cucumber (Ecballium elaterium) which is a low growing, Mediterranean plant with roughly hairy leaves, 1cm yellow flowers and bristly fruits that detach from their pedicels and squirt their seeds, and liquid, with deliciously violent force when ripe or when jostled. No, today’s plant is also a cucurbit but is from Central America and is related to a vegetable (strictly and botanically a fruit) called achocha (Cyclanthera pedata). These can be grown outside in the UK and are vigorous climbers that have odd fruits that vary in size from 5-12cm long that can be eaten when very immature and taste of cucumbers of left to mature when they can be stuffed or grilled and (unlikely as it sounds) taste of peppers.

An immature fruit

Cyclanthera explodens is not really grown as a vegetable although the tiny fruits do taste of cucumbers. The reason it is grown is for the excitement of the fruits, which rip themselves apart and fling their flat, jigsaw-piece-shaped seeds with great violence.

But first, a few basics. This may be a tender perennial but it is usually grown as a half hardy annual. I sowed seeds in April and they germinated within a week (in a temp. of about 20c) and they were planted out in late May by which time they were already 60cm high. Cold and dry weather with vicious winds did them a lot of harm and they did nothing for weeks but with some extra water they finally got their roots down and started to grow. And when they start to grow they certainly know what to do. I would say that they grow about 10cm a day and they are throwing shoots in all directions now, vertically and horizontally and in every direction in between. The leaves are an angular heart shape and not especially attractive but positively spectacular compared to the flowers! In each leaf axil is a cluster of flowers: one tiny, starry green female flower and a cluster of even smaller, male flowers, only about 4mm across (at a guess), so small you can hardly make out the anthers, and everything is in the same green as the leaves, stems and extraordinary tendrils.

A tiny fruit developing from the one female flower in the cluster and the tiny male flowers

The arches the plants are currently swamping are a bit exposed but, for now, the plants are coping. This would do really well on a warm wall but I am not sure it would deserve such a special place considering its modest aesthetic beauty.

But, looks aren’t everything and those minute flowers become curious fruits that are curved and, on the outside edge, are covered in soft spines. You could imagine a couple of territorial robins picking off these fruits and playing Pugil sticks when you leave the garden and lock the back door.

As the fruits mature they change colour slightly and develop a greyish hint and, along the angular corners at the top of the fruits the colour changes almost to grey and you know they are ready to POP. At this stage you often only have to touch them but other times need to gently squeeze them laterally and the tension built up in the curved upper part is released as the sides split and it rips the fruit open, throwing the seeds across the garden. I got my seeds this year from Real Seeds and they warn to wear goggles when doing this. The seeds are angular and flat and they could cause harm I guess if they were to impact into your eyes but I am not that careful.

Even though you know the fruits are going to pop there is still a rush of excitement at the speed and power of these little wonders and I have not tired of my little playthings yet. My only worry is that all those seeds are being scattered all over the garden and if we get a mild winter I might have more plants than I need next year.

Geoff’s rating

10/10 – it is unique, easy and so much fun

Garden rating

2/10 – it would not win a beauty contest with chickweed

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