A single bottle showed Dr. Nathaniel Bagshaw Ward a way to preserve growing plants.

In London, the 19th century start of the Industrial Revolution added coal smoke and sulphuric acid to its once-clean air. Only the toughest plants survived.

In a city square in 1829, Londoner Dr. Ward noticed that a glass bottle had fallen upside down, over a small fern and a young blade of grass. Four years later, they remained fresh, sealed in the up-ended bottle. When the seal was broken, the grass (which had flowered) perished, but the fern survived.

A physician with a passion for plants, Dr. Ward pondered on this puzzle and wrote several papers about the fern’s persistence. In 1849, he wrote a book on his observations. He hired a carpenter to build an airtight box with glass windows, to test his theory. Planted, it was the first terrarium.

From that design, others followed for early house plant growing. In line with Victorian tastes, they became fanciful, ornate and, I believe, quite in fashion.

There’s more! Wardian cases, as they were named, began to be used to transport “exotic” plants (or non-native) from one country to another. They could be tied to a ship’s deck, never need watering and would be securely fastened, protected from the elements.

When carried from other lands to England, plants in Wardian cases were more likely to live. With this expanded importing grew the popular craving for more exotic plants. Here was another business. Explorers roamed the globe, seeking to furnish food and decoration. Plant companies – some still in business – sent explorers into unknown territory. Our landscapes have changed in the last 200 years on that account.

When I took cuttings from a poinsettia this month (first putting on rubber gloves because the sap may be irritating), I stuck them in a small planting box of wet soil and then enclosed it in a clear plastic bag. I blew the bag up and fastened it tightly, making a sheltered environment for the cuttings. There’s enough moisture to furnish humidity and no watering is needed until I see new growth. I have furnished the rooting cuttings with a version of a Wardian case, 21st-century-style.

Thank you, Dr. Ward!