John C. “Jack” Lowry, a nurseryman and co-owner of Lowry & Co. and a collector of vintage automobiles who made plant deliveries to clients in a black Cadillac hearse, died July 27 of lung cancer at his home in the Phoenix community of Baltimore County. He was 87.

“I was a customer of Jack Lowry’s but he was a vital mentor of mine,” said Chris Snavely, who since 1971 has owned Snavely’s Garden Corner in Chambersburg, Pa. “And because I knew Jack from the very beginning of my business and through all the years, our relationship was not only a valuable business one, but also a valuable personal one. I was 14 when I first got to know him, and that goes way back 50 years.”

John Cathcart Lowry, the son of William Fleming Lowry Jr., an American Car and Foundry salesman, and his wife, Martha Ryan Lowry, a nationally recognized floral designer and author of “Floral Art for America,” was born and raised in Bethel Park, Pa.

He was a 1950 graduate of Bethel Park High School and enlisted in the Army. He served in Korea as a mechanic and officers club bartender, family members said.

After being discharged, he earned a bachelor’s degree in horticulture in 1958 from Penn State, and began his professional career as a horticulturist and garden designer for the Towson Nurseries store in Cockeysville.

In 1958, he married the former Marilyn Jean Bushyager and settled on Sweet Air Road in the Phoenix neighborhood, where they raised three children.

The couple began their business, Lowry & Co. in 1964, and Mrs. Lowry, who was known as Jean, served as secretary-treasurer of the plant and horticultural business, which represented nurseries from coast to coast.

Mr. Lowry, who was president of the firm, was a collector and purveyor of fine trees, and he furnished plants and horticultural products to garden centers, landscape firms and horticultural distribution centers.

In the early days of the business, Mr. Lowry, who had a passion for vintage autos, purchased a 1953 black Cadillac ambulance-hearse, which he converted to transport plant samples to clients.

“My father managed a small garden center in Hagerstown, and Jack Lowry first knocked on the door of the garden center approximately in 1962,” Mr. Snavely remembered. “He pulled up to Dad’s store with a hearse that he had modified for his needs filled to capacity with plants.”

Said Mrs. Lowry in a 2017 biographical sketch: “Jack was known for that hearse and people still ask if we have it.” She reminisced about the early days of the business “when there were no computers or fax machines, and all Jack needed was a pen, an order blank and a car.”

A daughter, Nancy Lowry Moitrier of Annapolis, wrote in a biographical profile of her father: “His successful career as a nursery representative was built brokering nursery materials from the Northwest, the South, the Midwest and the Mid-Atlantic regions of the United States. He supplied plant materials to hundreds of garden centers, nurseries and wholesale distribution centers in the Mid-Atlantic region.

“His knowledge and sales savvy techniques enabled many small boutique growers of exceptional plants to gain a foothold and a wider audience. His connectivity skills helped their businesses grow and prosper. He put little known, good horticultural growers, on the map. With his many horticultural connections, he had the ability to locate and deliver interesting plants in exceptional sizes for special gardens or Landscape projects.”

Said Mr. Snavely: “Jack was a character and that led to a lot of relationships coast to coast.”

A trademark of Mr. Lowry’s was conducting business with a handshake, which to him meant a solid agreement, and out of his business relationships grew lifelong friendships.

Mr. Lowry was active in organizations that promoted horticulture, and he played an important role in the establishment of the Mid-Atlantic Nursery Trade Show, which will celebrate its 50th anniversary next year.

He had served on its board from 1974 to 1979 and was president in 1977.

Mr. Lowry was on the board of the Maryland Nurseryman’s Association from 1967 to 1971, and served two terms as president. In 1984 to 1985, he was on the board of the Landscape Contractors Association of Metropolitan Washington.

He was on the board of the American Horticultural Society, one of the nation’s oldest national gardening organizations, from 2008 to 2010.

Mr. Lowry was still working at his death.

“He loved work, and work was his life,” Ms. Moitrier said in a telephone interview.

Mr. Lowry brought passion to his many collections, his daughter said.

He enjoyed collecting, restoring and showing classic vintage cars from his collection, which included Cadillac limousines, Lincoln-Zephyrs, which were built from 1936 to 1942, Ford Thunderbirds, and Mercedes-Benzes.

One of his outstanding cars was a 1948 Cadillac limousine painted a “beautiful burgundy color,” his daughter said.

During the 1970s, Mr. Lowry was a board member of the Lincoln-Zephyr Club.

His collecting interests ranged from cars to marbles, whiskey decanters and radios, and even clocks, keys and flashlights.

Mr. Lowry also collected plants, and he and his wife’s 1-acre garden was frequently included on tours organized by the Maryland Horticultural Society, the Annapolis Horticultural Society and the Pennsylvania Horticultural Society.

“In a suburban development in Phoenix, Maryland, it’s easy to spot Jack and Jean Lowry’s home. Their acclaimed collection of trees and plants begins curbside,” Baltimore Style magazine reported. “An artistic, year-round tapestry of conifers, Ginkgoes and Japanese maples — highly textured and in a spectrum of yellows, greens and reds — offers the Lowrys screening from the road, and their neighbors a glimpse of a first-class garden more than five decades in the growing.”

Mr. Lowry also enjoyed observing and feeding the birds that visited the garden.

He was a member of the Hillendale Country Club, where he was instrumental in designing and maintenance of the grounds of the clubhouse after it was rebuilt in 1993. He also enjoyed golfing and played in the club’s Men’s Weekly Twilight series for more than 20 years.

A memorial service will be held at 1:30 p.m. Saturday at Chestnut Grove Presbyterian Church, 3701 Sweet Air Road, Phoenix.

Mr. Lowry’s wife died last year.

In addition to his daughter, he is survived by a son, John Ryan Lowry of Finksburg; another daughter, Kim Hultberg of Forest Hill; and four grandchildren.