Penn State Master Gardeners Bonnie Gardner and Ginny Mowery entertained questions and offered insight to gardening problems Monday night at the third of four garden tip programs offered at the Shippensburg Public Library.

Backyard gardeners asked for advice about rhubarb, Concord grape vines and the branch of a shrub bearing lovely yellow flowers that a man brought with him.

While searching their own memory banks and consulting a variety of references in books and Penn State Extension printouts, the teachers digress to share vexing problems they struggle with at their homes.

Monday’s session was the third of three monthly programs that culminate at 6:30 p.m. Aug. 13. Weather permitting; the classes are outdoors, but shift inside if weather demands.

Monday’s garden info clinic benefited from the ample shade and fresh breeze that stirred after days of sultry conditions.

Cindy Mathes approached Mowery about Concord grape vines she transplanted from her father’s backyard after he was unable to tend them. She said tendrils of the vines stubbornly refuse to climb chain link fence and lattice she provided and asked what to do.

Mowery said manual manipulation is the key.

“You just have to take the vines and gently place them on the lattice,” Mowery said. “If they continue to spread on the ground, they’ll just rot.”

Mathes also learned that her inclination to water the grapes is ill-advised.

“Grapes like it dry,” Mowery said. “They get sweeter that way.”

That will mean less work for Mathes.

“I’ve been lugging water out there every day,” she said.

Mowery also covered some rudimentary pruning tips for the grape vines, telling Mathes to prune in February.

“If you wait too long to prune the vines will bleed heavily,” she said.

Mathes says she wants to turn her grape crop into juice or jelly.

Wayne Schopf came to the garden advice center toting a small branch of a shrub. He wanted to know what the plant was.

“I wanted to paint the porch last year and I had to cut this all the way to the ground to do it,” Schopf told Gardner. “It grew back this year, and I want to know what it is. It was little yellow flowers, but I know it’s not forsythia.”

Gardner indentified the twig as kerria japonica, a deciduous plant of the rose family that’s native to Japan.

Gardner says the shrub bears delightful bright yellow flowers, but colonizes and spreads if not tended. Schopf left happy with his newfound information.

Diana Shaw clearly had something on her mind as she advanced across the library parking lot.

“Could I borrow you guys for about a month to work in my backyard,” she asked as an intro.

She suggested she has several challenges in her yard, but focused on the red rhubarb plants that “won’t turn red.”

Shaw said, “We bought this house from a guy who said there were red rhubarb plants in the backyard. You can see he planted stuff for years, but the rhubarb won’t turn red.”

Mowery told Shaw the answer is probably simple but unsatisfying.

“It’s probably green rhubarb,” Mowery said.

The news wasn’t what Shaw wanted to hear.

“I can’t bring myself to eat green rhubarb,” she said. “It’s not what you use in strawberry pie.”

In the course of their discussion, Shaw and Mowery touched on the unwelcome milkweed that grows in the backyard.

Mowery said there is one great benefit to milkweed.

“It’s the only place a Monarch butterfly will lay its egg, so you’re doing your part for Monarchs,” Mowery said.

Gardner says she identifies with the problems and concerns that backyard gardeners contend with in trying to create a lovely setting.

“I have Queen Anne’s lace invading my yard from one side and wild garlic from the other,” Gardner says. “It’s a constant struggle, but what we urge people to do is stay away from strong chemicals. You just have to keep picking and pulling, and even then you’ll always get a stray seed blowing in.”