This is the VOA Special English Agriculture Report.

Trees and plants are called ornamentals if their main job is to add beauty and interest to a garden. Dogwood trees, for example, are a popular ornamental in some areas because of their white or pink blooms in the spring. Cherry and plum trees can also add beauty to landscaping even if they never produce fruit.

Ornamental trees and bushes or shrubs can serve other useful purposes besides just looking good. Some also smell good and can be used to make scented oils -- for example, lavender and lilac.

Ornamentals can be used to mark the border of a property or to provide privacy from neighbors. They can be used to hide trash cans and storage sheds.

Most ornamentals have the same needs as other plants -- water, mulch, pruning for shape and inspection for pests. But master gardener Bob Orazi says, "Most of them take care of themselves after the first six months."

Bob Orazi is a horticultural adviser in Howard County, Maryland. Years of experience have shown him that people often decide to plant an ornamental bush when they see one in bloom. They might see the yellow blooms on a forsythia bush -- one of the first signs of spring -- and decide to plant one. But he says most ornamentals are better to plant just before their leaves open.

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 4.5 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.

mulch: material, for example, decaying leaves, that you put around a plant to protect its base and its roots, to improve the quality of the soil or to stop weeds growing 覆蓋物，護(hù)根（用以保護(hù)植物根基、改善土質(zhì)或防止雜草生長）

forsythia: a bush that has small bright yellow flowers in the early spring 連翹，金鐘花（灌木，早春開小黃花）

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（來源：VOA 編輯：崔旭燕）