Some ornamentals and other plants are sold with their roots in a ball of dirt held together with burlap. But David Robson of the University of Illinois Extension says more and more plants are grown in containers. They are easier to ship that way.

However, the roots may become encircled by growing around and around in the pot. So his advice is to pull the plant out of the container, then cut the bottom half of the root ball into four parts.

This process is known as "butterflying." The bottom of the root ball will look something like the spread-open wings of a butterfly. David Robson says planting the root ball this way will improve growth.

DAVID ROBSON: "It is amazing on a tree or shrub how much faster growth you will get. But you do have to remember by butterflying, you are cutting down the overall height of that root ball. So maybe butterfly it first and then measure how tall your root ball is. Then dig your hole. Make sure you do not dig it too deep so the plant is sitting below the soil line."

He also advises against letting shrubs grow taller than four and a half meters.

DAVID ROBSON: "[If] some shrubs get too tall, you start losing their ability to produce good flowers."

In that case, your ornamental plant might not be so ornamental.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. For more gardening advice, and a link to captioned videos of our reports, go to voaspecialenglish.com. I’m Bob Doughty.