Emma Klein’’s Christmas tree this year was the same Norway spruce her family has celebrated with every year since 2018. Mr. Sparkles, as her three-year-old daughter calls it, is one of about 1,000 living trees growing in a pot rented by London Christmas Tree Rental each holiday season. Observing piles of spent trunks on the sidewalk in London one January, director and co-founder Jonathan Mearns was inspired to launch the business in 2018, offering 30 live trees. Over the years, it has grown to about 1,000 trees. Living trees can be available for up to eight holiday seasons. Each year in early December, Mearns and his team set up four pick-up points around London. Over the three-and-a-half weeks the trees spend in homes, renters keep them watered and then drop them back off at collection points in early January.