‘Sir, what's the difference between a cactus and a succulent?'

SUCCULENTS: their very name is mouthwatering— unless, of course, you’re one of those gardeners who lumps them with cacti, their spiny cousins. ‘Sir, what’s the difference between a cactus and a succulent?

- Alen Titchmarsh

My question was directed at Harry Rhodes, my junior-school teacher, who was passionate about both groups of plants and who would raise them in the little greenhouse in his back garden to sell at the church bazaar in the 1950s. They were all the same price: sixpence a pot.

By growing a range in pots, we can bring the world to our doorstep

His reply was swift and concise: ‘Well, all cacti are succulents, but not all succulents are cacti.’ He must have noticed my furrowed brow. ‘The succulents that have spines we call cacti; the ones without we just call… succulents.’

The matter was settled—and so was my fondness for a group of plants that began then, at the age of nine, with a single potted specimen bought from Mr Rhodes. Its label (a scrubbed and neatly inscribed lollipop stick) bore the legend Bryophyllum pinnatum. It was a liver-spotted succulent with tiny little plantlets along the edges of its leaves. Brilliant!

For half my weekly pocket money (a shilling) I had 30 or 40 plants rather than one, as the tiny plantlets rooted with ease in other pots of sandy compost. Within a month, I could have had my own plant stall at the church bazaar. Since then, my gratitude to Mr Rhodes has never faded.