Lop it off. That was the advice repeated frequently at a recent class on All About Pruning.

While pruning might not be a gardener’s favorite task, about 70 people spent a chilly Saturday morning at a free, information-packed class offered at the Natural Gardener to learn more about the ins and outs of this essential job. The class covered a broad range of pruning-related topics.

For starters, Stacie Primeaux, a co-presenter and horticulturist with the garden center, said there are four reasons to prune: to train or shape; to maintain plant health; to improve quality of flowers, fruit, foliage and stems; and to restrict growth.

Many people are “afraid to prune,” worried that they will hurt or kill the plant, Primeaux said. But class members were encouraged to be fearless.

Citing a gardening axiom, Primeaux said that “people heal; plants seal.”

“Plants seal any wounds they incur,” said Linda Wall, a co-presenter and horticulturist, after the class.

“It’s always good to prune the dead off anything,” Primeaux said. Pruning is best done at the time of year that is going to damage the plant the least, she said. It varies depending on the plant, she said.

“Get to know your plant," she said. “There are different indicators. It wants to be shaped.”

For example, Wall said, roses love to get pruned. They should be cut to resemble an upside-down umbrella, which helps increase airflow, she said.

Gardeners should keep in mind their objective, such as restricting or encouraging growth, Wall said.

Perhaps counterintuitively, “The more you cut, the more blooms you’re going to get (later),” Wall said.

“In spring the plant uses the energy in its roots to rebuild itself. In fall it sequesters that energy back into its roots to preserve it from being damaged by the cold, by the winter. … Whenever you prune in the winter, you are not cutting that much off. It has plenty of energy still to regrow itself,” Wall said later.

In general for pruning plants, “You want to cut at a 45-degree angle away from a node … the little bump sticking out,” said Primeaux, because “when the rain comes, we want the rain to fall away.”

“The rain should easily fall off the cut end,” Wall said later.

Also, “We want to get a nice, clean cut,” Primeaux said.

Overall, Wall said, it is wise to prune out anything where the branches are growing crosswise with other branches or those that are growing toward the middle. This too will increase airflow, she said.

“Anything that looks like it is crowding, cut it,” Primeaux said.

Don’t just lop off the top, also. Showing an example of grasses, “When someone just cuts across the top, (it) looks like sticks across the top,” Primeaux said. “I want it to look like it wasn’t pruned.”

When to prune

As a guideline, prune about two-thirds of a plant during winter and one-third during growing season, and then “stand back and look at it,” Wall said. “You can always cut more, but it’s really hard to put it back.”

In the “flip-flop weather” Central Texas has experienced lately, Wall recommended in general to “wait until after a couple of freezes.”

“Don’t cut before a hard freeze,” Primeaux also cautioned. That’s just “invigorating them to put out new growth and then the freeze comes” and hurts them, she said.

Of course, she added, “We all have our murder stories.”

Wall and Primeaux stressed the importance of using quality tools and keeping them well-maintained. According to a handout given at the class, some of the most beneficial tools include small hand shears, bypass pruners, loppers, pruning saw, shears and pole pruners (for hard-to-reach branches).

Pruning gloves are also helpful, especially if cutting anything sharp or thorny, Primeaux said.

Regarding upkeep, “Once you sharpen your pruners, it’s like you bought a brand-new tool,” Primeaux said.

A sharpening stone “is a great friend,” Wall said, as well as pruning oil if tools are sticking.

For sterilizing tools and not spreading disease, Primeaux suggested washing tools with a solution that is 1 part bleach to 9 parts water.

For general cleaning, you can use dish soap and water, Wall said.

When pruning, class members were encouraged to visualize “what you want it to look like” and then experiment, Wall said. “See what happens,” she said. “See if you like it. If you don’t,” lop it off, she said.

For pruning of trees, however, Wall said calling a professional could be needed because trees “are a big part of the value of your land.”

For additional information, including a calendar on the best time of year to prune certain plants, they recommended a Grow Green guide about pruning. (Grow Green “is a partnership between the City of Austin Watershed Protection Department and Texas A&M AgriLife Extension,” according to a guide. More information can be found at www.growgreen.org.)

In the audience, Bobbie Nehman, 76, who describes herself as a “garden junkie,” nonetheless said, “Pruning is definitely a puzzle.” After the class, she said she realized that she had a lot of pruning to do in her garden.