And the winner is...

When you're choosing plants, it's always good to have the advice of someone else who has grown them -- particularly when it's a plant you're making an investment in, such as a shrub or tree. That's one big benefit of nonprofit groups that rigorously test various plants and give awards to those that are outstanding.

For 30 years, the Pennsylvania Horticultural Society has tested trees, shrubs, vines, and other woody plants to determine which thrive in the mid-Atlantic region -- from New York to Washington, D.C. Its Gold Medal Plants program has recognized more than 100 outstanding specimens during that time.

For 2009, five more plants have been added to the list: one tree, two shrubs, one ground cover, and one plant that can be a shrub or a tree, depending on where you grow it and how your prune it.

Here's a quick run-down of the winners, all of which prefer full sun but will tolerate partial sun and four of which are deer-resistant:

Gardeners know that good garden plants with true-blue flowers are hard to find. And that goes doubly for shrubs and trees. But Vitex agnus-castus 'Shoal Creek' (chaste tree) not only has excellent blue flower spikes but blooms all summer, has disease-resistant leaves, and attracts butterflies. Penn. Hort. says it's "highly deer-resistant" in the mid-Atlantic region (deer-resistance varies by region). It's for hardiness Zones 6 to 9.

Privet honeysuckle (Lonicera pileata) is a low-growing shrub that forms an evergreen ground cover on difficult slopes. As a bonus, it's also deer-resistant and produces violet-colored fruit for wildlife. Zones 6 to 8.

There's something neat-looking about a shrub that grows in a pyramidal shape . Spicebush (Lindera glauca var. salicifolia) not only does that but provides four seasons of interest in your landscape -- foliage that's emerald-green in spring and summer, yellow-orange in the fall, and tan hanging on long into the winter, plus black fruit in fall. Zones 5 to 7.

A native ground cover -- fragrant sumac (Rhus aromatica 'Gro-Low') is another highly deer-resistant winner (at least in the mid-Atlantic). It also attracts wildlife with its fuzzy red berries and shines in autumn with bright red and orange foliage. It's also drought-tolerant and good for urban areas. Zones 3 to 9.

A weeping katsura (Cercidipyllum japonicum 'Morioka Weeping') is a graceful tree with blue-green foliage that's also deer-resistant. It will grow about 25 feet tall in 10 years or so, but eventually reach its full height of 40 feet. Zones 4 to 8.

Are these plants for you? You'll probably want to ask at your favorite nursery before deciding. But especially if you live in the mid-Atlantic states, they're certainly worth serious consideration.