Colorado Public Radio: The climate was perfect. Many hours of direct, high-altitude sunlight, warm days and cool nights. An irrigation ditch built in the 1880s brought water from Platte River Canyon into Denver. That allowed greenhouses to be built and the floral industry grew rapidly. The blooms were delivered by horse-drawn carriages warmed by charcoal heaters in the winter to keep them from freezing, according to a Colorado State University paper on the industry.

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