A flower that arrived from the east 

Start with the plant, because the plant explains the price. The tulip is not a native of the Low Countries. Wild species grow across Central Asia and Anatolia, and by the sixteenth century cultivated tulips were a serious feature of Ottoman garden culture, prized in Istanbul long before anyone in Amsterdam had seen one.

It travelled west through the usual channels of the period: diplomats, merchants, and the letter-writing network of botanists who traded seeds and bulbs the way scholars traded manuscripts. The decisive figure is Carolus Clusius, one of the great botanists of the age, who took charge of the new physic garden at Leiden in 1593 and planted tulips there. From that garden and others like it the flower spread into the hands of wealthy collectors across the Dutch Republic and the German lands.

What made it desirable was partly novelty and partly the shape of the thing. A tulip is architecturally clean, saturated in colour, and it arrives after a long grey winter. It also flowers for roughly a week, which is a peculiar property for a luxury good. You cannot display it year round. What you own for the rest of the year is a brown bulb in the soil and the knowledge of what it will do in April.

Now the economics. A tulip can be grown from seed, but a seed-grown bulb takes something in the region of five to seven years to reach flowering size, and it does not reliably reproduce the parent's colouring. The fast route is vegetative: a mature bulb produces offsets, small daughter bulbs that are true copies. A good bulb might yield two or three offsets in a season, sometimes fewer. That is the whole supply mechanism for a named variety.

Sit with that number. If demand for a fashionable variety doubles in a year, supply cannot follow, and it cannot follow next year either. There is no factory to expand and no substitute the collector will accept, because the point is owning that specific named cultivar. Meanwhile the buyers were the richest people in the richest economy in Europe, in a republic swollen with trade profits from the Baltic, the Mediterranean and the East Indies, and looking for objects that signalled taste rather than mere wealth.

So the ingredients were assembled early and quietly: a genuinely new asset, an admiring audience with money, a supply curve that answers in years rather than months, and a market where the connoisseurs set the terms. None of that is a bubble yet. It is simply an expensive flower.

The strangest part came next, because the most expensive tulips of all owed their beauty to a disease.