You are touching on one of the great untold stories of the tulip mania.

The mania got its start because there was a small group of very wealthy Dutch regents (members of the republic's upper class) who competed with each other to acquire the most beautiful tulips. They did so predominantly because the tulip was very rare (it had been introduced into the Netherlands on in the 1570s, and was very slow to propagate, taking seven years to grow to a bulb from seeds) and also because it was remarkably beautiful (Dutch tulips of this period were infected with a virus that caused them to "break" into remarkably vivid patterns and colours). The virus also weakened the plant and made its reproductive behaviour unpredictable – both factors that made it harder to acquire large numbers of the most highly valued tulips, and hence increased competition to own the few samples of the best flowers that did exist. Letters written at the time suggest that there were only 12 known examples of the single most expensive flower, a variety known as Semper Augustus.

The regents who did collect and display the tulips planted them in their country houses. There was a fashion among the wealthy for investing fortunes in their country estates at this time. This was the product of three key factors: the relative drabness of the Dutch countryside (the United Provinces were described by one English visitor as "‘an universall quagmire... the buttock of the world"); the sudden influx of wealthy into the Netherlands produced as a result of the success of the Dutch East India Company in the long-distance spice trade; and the Calvinist religion practised there, which frowned heavily on ostentatious displays of wealth. One exception to this rule was that it was considered permissible to celebrate natural beauty, since this was a gift from God. As a result, the – semi-competitive – investment of money in beautiful country gardens was considered acceptable and was one of the few outlets that the new class of Dutch super-rich had to demonstrate and celebrate their success.

So we have a situation in which a small group of seriously wealthy individuals are channelling their interest and investment into their country homes, and a flower - the tulip - which for good reasons is considered the ultimate demonstrator of beauty, taste and wealth. This explains the initial sharp rise in the value of tulips, which took place roughly from 1620-1633. But the market in tulips that existed at this time remained a rational one, constrained by the classic laws of supply and demand.

What seems to have happened next was that the riches of the tulip trade attracted the attention of the lower classes of the Netherlands. Probably this happened because the regents did not cultivate tulips themselves – they hired professional gardeners to do the work for them. Thus there was a conduit of information from the country estates to the taverns of local towns, and word of the new value and its value could have reached the less well off, a group who in this period typically laboured 14 hour days. It's not difficult to see how the prospect of becoming wealthy by growing and selling tulip bulbs (plant a bulb, sit and wait for six months for it to flower, sell it) seemed more attractive than endless grinding physical labour, and how some ambitious Dutch artisans might be tempted to set themselves up in it.

The reality, though, was that the tulip trade that subsequently grew up in the Netherlands, and was responsible for what we now think of as the tulip mania, was almost entirely divorced from the regent market for tulips, and indeed from the Amsterdam stock market (which never traded tulips). It was pretty much a parody of real trading, one that took place in taverns, involved mostly local artisans who were looking to make a quick profit, and occurred when most of the participants were tipsy-to-drunk, to boot.

We have to remember, too, that the tulip bubble was the first economic bubble identifiable as such, so the idea that prices could go down as well as up may not have occurred to many of the participants till it was too late. They had seen prices rise consistently for several years and a number of them, at least, must have supposed involvement in the trade was a sure way to make some easy money. But for these new traders, involvement in the tulip trade meant profiting as quickly as possible from the assets they - temporarily - possessed. Not only did they have no interest in planting the bulbs or admiring the flowers - they knew that the worst thing that could happen would be to left in possession of bulbs (or the paper contracts that soon supplanted physical flowers in the trade) when the time came for the flowers to bloom and be lifted from the soil. It was at that point that all contracts were supposed to be settled, and most of the people involved in the trade planned to have "cashed out" before that became necessary. So the answer to the question you posed is that the traders planned to pass on their liabilities - and the bulbs - to some greater fool ahead of lifting-time. This explains the frenzied nature of the trade in the early weeks of 1637, before boom was followed by inevitable bust.