Why Bourbon vanilla is the most popular type of vanilla in the UK, including Manchester?
Madagascan and Bourbon vanilla are actually the same. Bourbon vanilla from Vanilla planifolia Andrews is the most popular cultivated variety, mainly from Madagascar. Vanilla planifolia is very much the same variety, originating and grown in Mexico, but has now become synonymous with Madagascar. Mexican vanilla is produced in considerably smaller quantities and marketed as vanilla from its land of origin. Bourbon vanilla is the preferred type of vanilla used in the UK, including Manchester.
Vanilla planifolia, is the species most commonly used in vanilla extracts
Vanilla planifolia stock undoubtedly originated in Mexico, vanilla’s birthplace, but cuttings were taken to other tropical nations beginning in the 1700s. In the 1800s, the French established large plantations on Reunion, known then as the Ile de Bourbon. Now you know how the name Bourbon vanilla came into being. Vanilla planifolia is the species most widely used in extracts. Vanilla planifolia is the most esteemed variety simply because of its aroma and flavor qualities.

Why usage of generic term Bourbon for Madagascan Vanilla is not right in absolute terms?
Originally the generic term Bourbon referred to vanilla beans grown anywhere in the Indian Ocean region. As Vanilla Planifolia was planted in various nations, the name followed along. As a consequence, Bourbon vanilla may or may not be from Madagascar. Although Bourbon vanilla and Madagascan Vanilla are still used interchangeably, vanilla beans are increasingly referred to by region rather than by this generic name now.
Bourbon and Mexican vanillas may be similar but not the same
Bourbon and Mexican vanillas are very similar in flavor simply because they’re from the same species, but there are some special characteristics with each as soil and rainfall variances create subtle flavor changes. They both possess the familiar natural vanillin flavor that we associate with vanilla ice cream and other vanilla-flavored desserts and beverages. Madagascar vanilla seems to be a little stronger in flavor compared to Mexican. Bourbon/Madagascar vanilla contains earthy, hay-like, creamy and spicy notes.
Indonesian vanilla can be very much like Bourbon vanilla, or it can have very distinguishing differences. Some growers harvest their beans very early, which imparts the vanilla a more woody, phenolic flavor. As the early harvest keeps the beans from fully evolving their flavor profile, it can be a bit harsher and not as flavorful.