More than 50 are known to be perennial and winter-hardy.

Add in a few winter-hardy herbs to your autumn-sowing programme.

It will make wines from winter-hardy fruits rather than grapes.

So much for the winter-hardy Christmas trees that must be planted outdoors eventually.

The species thrives in warm temperatures but is most often winter-hardy.

Sometimes the seed is winter-hardy, nature's way of perpetuating a species.

Winter gardens are dependent upon the cultivation of winter-hardy plants.

Winter-hardy plants grow during the winter, or at least remain healthy and dormant.

The effective growing season can be extended by autumn sowing with varieties that are winter-hardy.

Plants are winter-hardy and heat-tolerant throughout most of the United States.

They brought seeds of winter-hardy Russian wheat that became the major farm crop in this area.

The result of this process was the first truly winter-hardy alfalfa in North America.

The shrub is winter-hardy, but has little tolerance for shade, drought, or fire.

Large containers are the answer, since they provide secure year-round homes for winter-hardy small shrubs and trees.

However, not all geranium species are winter-hardy (see below).

Being winter-hardy, they are increasingly grown in Northern Europe.

Yucca elata and its subspecies are winter-hardy in central Europe.

"If it mutates ever so slightly and becomes more winter-hardy," he said, "that could be a concern."

Zantedeschia are relatively hardy plants, but some are more winter-hardy than others.

He says that bench-grafted trees are less winter-hardy.

The white fly is not a winter-hardy insect; it is killed by the first frosts.

Winter-hardy cactuses seem especially attractive at a time when drought plagues the Northeast.

A. So long as the soil is not frozen, it's possible to continue planting winter-hardy species right through Thanksgiving.

Although it could hardly be called invasive, this winter-hardy perennial will self-sow with relative ease.

When he started, he said, he found only two suppliers of winter-hardy cactus in the entire country.