We’re now in the arid greenhouse. What places come to mind? The hot deserts of Africa, or of the Arabian Peninsula? Right, but there are also cold arid environments around the world, like the Gobi Desert, in Mongolia.

In desert environments - whether hot or cold - only the real tough members of the plant world survive, as water can be lacking here even for years at a time.

You’ll know them by the name of succulents, or cactuses. They’ve developed a specialized tissue of voluminous cells rich in mucilage, which retains water. Some, like cactuses, have water in the stem, but others, like aloe, have it in the leaves.

And the wonderful thing is that similar adaptations are found in every desert on Earth, even if very distant from each other. If it works, it works! Here we can see two beds of plants from different arid biomes: America and Africa. Can you spot similarities?

In the arid American flowerbed, look for the creeping devil, Stenocereus eruca, which has a green stalk like all cactuses. Leaves? They’ve evolved to just a thorn to limit loss of water and at the same time defend against attack by animals.

Find how many different shapes the spines can have, from very short, just millimetres in length, to a few decimetres long, soft like bristles or stiff like needles, straight or curved.

In the African flowerbed, look for ice plants of the Lithops genus. To avoid being burned by the sun, they’re tiny. You’ll see that only two swollen leaves emerge from the sand. Take a good look at them, do you see the small transparent areas? That’s where the light enters and goes underground for photosynthesis. They’re almost invisible, blending in with the surrounding stones, until the moment of flowering when they attract a few brave pollinators with colourful flowers twice the size of the leaves.

In the desert, the strategy is to live in the moment. When it rains – and only then – the desert comes back to life and only for a few weeks. From seeds that may wait years to sprout, thousands of small herbaceous plants are born, develop and bloom, in a spectacular show of colour.