Brookside Gardens has been around for 50 years. Phil Normandy has been there for 40 of them. The other day, I tagged along with Phil — plant collections manager at the Wheaton park — as he visited some of the trees he’s had the pleasure of knowing and growing.

“Here’s a rare plant that’s common,” he said, looking up at a tall conifer standing a little beyond the Visitors Center.

Wait. A rare plant that’s common?

Phil told the story of the dawn redwood, or metasequoia, a tree once thought to be extinct, a tree once known only by fossils that preserved in stone its distinctive feathery leaves, a tree that in the 1940s was discovered growing in a valley in China when a Chinese botanist trying to lie low during World War II stumbled across a single example.

“Then he found 22 more in a nearby valley,” Phil said. After the war, the botanist sent seeds around the world.

“Now it’s become a landscaping staple,” said Phil. He planted this particular dawn redwood in 1996. It was about 12 feet tall then. It’s 80 feet now. “They grow like crazy. It’s a great tree story.”

Phil loves great tree stories almost as much as he loves great trees.

We walked farther into the garden. It was morning, so the day’s oppressive heat hadn’t yet descended. Montgomery County opened Brookside Gardens in 1969 after buying a nursery on the site run by a family called the Stadlers.

“Mr. Stadler asked, ‘Why would you want to put a garden in a frost pocket?’ ” Phil said.

The rolling landscape means that some parts of the 35-acre grounds sit in windswept hollows. Of course, that was 50 years ago. Since then, the USDA has adjusted the U.S. plant hardiness zone map to match our warming reality.

“This region has changed zones, from 6B to 7,” Phil said.

Plants that once died in the cold — crepe myrtles, camellias — now do just fine. But the winter-loving birches Phil planted years ago are stressed and dying.

We walked on a shaded path until we came to a tree with waxy leaves growing on wispy branches that cascaded to the ground. It was an inviting display, like a curtain waiting to be parted.

“Look up into this thing,” Phil said. “Isn’t it amazing?”

It was a weeping katsura. Phil has known it since it was a toddler. It came in 1981 directly from Japan. “They like rare things there,” Phil said.

Brookside had secured a permit to import about 20 weeping katsuras, which were little four-foot-sticks then, their roots packed in moss. (No dirt allowed through customs.)

Phil planted the sticks in pots, fussed over them, let them grow strong. Then in 1984 they were big enough to put in the ground. There are two on the property.

“I did not know it was going to look this gorgeous,” said Phil. “I’m very proud of this tree.”

The saying goes that a society grows great when old men plant trees whose shade they know they’ll never sit in. But if you’re Phil Normandy, 67, and you started planting trees when you were a young man, you get that chance.

“I’m very fond of this tree,” Phil said, looking up at a pond cypress. It’s not as tall as it once was. The top half broke off in a storm in 2014. Some people at Brookside wanted to take the tree down.

Phil argued against it.

The tree stayed, its trunk leveled off about 30 feet up. Since then branches have shot up around the scar.

“I have a personal attachment to this tree,” Phil said. It’s the first tree he ever planted at Brookside Gardens.

“Also, it shows homeowners that not all trees are perfect.”

Phil asked, “Do you have time to see the Al Capone cherry tree?”

Well, sure, I said. Is Al Capone buried there?

“No,” Phil said. “I’m pretty sure Jimmy Hoffa’s not buried here, either.”

We walked toward the Japanese-style garden and stopped at a perfectly pleasing, if unexceptional, cherry tree. Phil began to explain where it came from.

After Al Capone was released from Alcatraz, the gangster went to Baltimore hoping the doctors at Johns Hopkins Hospital could do something for the syphilis that riddled his brain. Hopkins declined to admit the mobster, but Union Memorial Hospital had no such qualms.

In gratitude, Capone gave two weeping cherry trees to the hospital. One was cut down in the 1950s to make way for construction, but the other is still there. An arborist in Harford County, Md., took cuttings from it and grew offspring.

He never planned to sell them, Phil said, but just wanted to ensure the future of the Capone tree’s lineage.

“I said to him, ‘You really need to sell me some of those trees,’ ” Phil said.

Phil got his tree. In April, he planted it at Brookside Gardens.

“I just had to have it for the story.”

Twitter: @johnkelly

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