The dormant season does not have an official beginning to mark on a calendar, but depends on a combination of factors, beginning with the individual plant’s biological clock, with which the plant responds to day-lengths.
Another important environmental factor is temperature: lower temperatures trigger dormancy, and higher temperatures can stimulate growth. Climate change has modified the annual cycles and geographic distribution of many plants, and will continue such changes. Phenology is the study of periodic plant and animal life cycle events
Rather than delving into the science of dormancy, let’s consider seasonal projects for the gardener. There are many priorities to schedule over the next few months.
As the leaves fall, and the “bones” of your trees and shrubs are exposed, look for ways to improve them through pruning. In general, use sharp tools, begin by removing branches that are broken or diseased, and don’t remove more than one-third of the canopy in one year. As is often true in gardening, there are exceptions: for some shrubs, severe or renewal pruning is appropriate. Extensive pruning of roses, for example, stimulates new growth and abundant blossoms. Several other multi-branched shrubs, e.g., salvias, can be cut to their primary structure or to near the ground before spring growth emerges.
Many gardeners are hesitant about pruning, concerned that they could hurt their plants. Pruning can be done badly so a little time with a pruning book would be instructive. The positive perspective is that pruning improves a plant’s form and stimulates new growth.
The photo is from the University of California publication, Pruning Small Trees and Shrubs, which is available free online.
A good approach includes observing pruning’s effects during the early spring.
- Walk through the garden with a critical eye, to spot opportunities for improvement.
- Transplant or give away plants that have grown too large, or not working in the landscape.
- Install new plants now, to let the rains irrigate them as they establish roots.
- Add mulch to cover any bare ground between plants.
- Plant a cover crop in any fallow planting area.
- Force a bulbous plant to bloom indoors. Paperwhites (Narcissus papyraceus) are popular, but are so strongly fragrant that restraint can be prudent, i.e., don’t grow a lot.
- Sharpen your garden tools, or have them sharpened professionally.
Mark your Calendar for the New Year
January 8, 9 & 10 — The 42nd Annual Santa Cruz Fungus Fair, at Loudon Nelson Community Center, Santa Cruz
January 10 — Annual Scion Exchange, Monterey Bay Chapter, California Rare Fruit Growers, at Cabrillo College, Aptos
Late News: Broom versus Leaf Blower Challenge!
The broom versus leaf blower challenge between Ken Foster (on the broom) and Brent Adams (on the leaf blower) will take place Friday December 11th at high noon next to the Westside New Leaf Community Market, at the corner of Fair Avenue and Ingalls Street in Santa Cruz.
Gasoline-powered leaf blowers pollute our environment, disturb our peace, and change our climate. They might be justified for their seeming efficiency, but that too has been questioned. The Broom versus Leaf Blower Challenge, designed as a fair completion, is worth witnessing (sorry about the late announcement). I’ll report the results in next week’s column.