Homegrown: Is the weather too cold for gardening?

Weather is always a hot topic for gardeners, and this year has given us plenty to talk about — a spring heat wave, a dry autumn, and a cold start to winter.

Our freezing December weather will keep the chatter going for months, as well it should, if only as a reminder merely to keep an eye on plants that appear damaged rather than take action with pruning shears.

That can wait until warmer days in spring after signs of life let us know what tissue is dead and what is not.

When growth doesn't resume at any point, removing a plant is usually the only option.

Trimming away stems and branches now on citrus, sages (Salvia), hebe, angel's trumpet (Brugmansia), and other tender or semi-tender trees and shrubs removes what little protection remains for lower parts of plants.

Russian sage (Perovskia) is a good example of a sub-shrub — a perennial with a woody base — with foliage that dies back in severe cold but is quick to reappear in early spring. Allowing perovskia stems to stand tall during winter has more than one benefit.

Besides insulating the woody base, dead stems turn a ghostly white that is wonderfully attractive against an otherwise dull background.

Ground isn't frozen: Even though some have described our December conditions as frigid weather, these cold days don't approach what colder climes experience. Our soil is cold, but not frozen. We can still put a shovel in the ground, though only bulbs and established plants with good root development can handle movement right now into moistened soil.

Although erosion from rain and runoff isn't a current threat, bare surfaces always benefit from being covered. During dry spells, mulch helps keep the soil moist and protects roots.

Fallen leaves provide a fast and easy solution if you have no other materials on hand, but they come with a downside. Unless watered down to compress and hold them in place, they may look messy before they slowly decompose.

Time for action: Besides gathering up fallen leaves and faded annuals and perennials for mulch and compost, what is there to do in the garden?

Some would say that a busy time awaits as soon as we turn the calendar page. January is typically the beginning of pruning dormant woody plants such as roses and fruit trees and applying dormant sprays. Keep tools sharp as you work and exercise caution with both tools and sprays.

In a normal year, we would limit garden activity to avoid trampling wet ground, but that isn't a worry at this point.

Right now, there is a window for scoping out where we would like to walk in winter but usually cannot. This may be just the opportunity needed for adding hardscape such as a pathway or two where walking is welcome when soil eventually becomes saturated and soggy.

If you already have paths covered with recycled wood chips, this is a good time for building up their depth. A thick layer discourages weeds and slowly breaks down to add nutrients to the surrounding soil, as long as you don't put a barrier cloth underneath.

Watering reminders: Outdoor containers dry out faster than we might suppose on cool, sunny days, but beware of the danger of overwatering that causes root rot. Probing with a trowel to determine moisture in the lower levels of pots is always a good idea.

Because indoor air can be just as dry as that outdoors, houseplants may suffer from lack of humidity, and soil in pots tends to dry out fairly rapidly. If you're tempted to water more frequently, first check the soil.

Like their cool-weather cousins, tropical and sub-tropical indoor potted plants also take a rest in winter. When roots are inactive, excessive moisture in the bottom of the pot can promote root rot that may go unnoticed until the plant begins to look droopy.

When only the soil surface appears dry, we're tempted to water once again, adding to a slow decline in plant health.

Use a probe or a finger to test for moisture and wait to water until you feel dry soil an inch or two below the surface.

(Rosemary McCreary, a Sonoma County gardener, gardening teacher and author, writes the monthly Homegrown column for The Press Democrat. Write to her at P.O. Box 910, Santa Rosa, 95402; or send fax to 664-9476.)