By T. Eric Nightingale
They have been waiting patiently, and now their time has come. Creatures that love the wet weather are finally able to come out and do what they do best: make you miserable.
For many Napa Valley gardeners, this time of year can be frustrating. We have been watching our plants prosper under relatively consistent conditions for months, then the weather shifts. It starts to rain, and if we're lucky, it rains a lot.
The wet weather is a game-changer. Having grown up in the damp Pacific Northwest, I know this game well. Particularly familiar to me is the battle against mold, mildew and other fungi.
These plagues seem to come from nowhere and not reveal their presence until they are such a problem as to make you question your commitment to gardening. Only the truly devoted (or crazy) will find themselves scraping white, stringy fungus from a clogged planter box on a dark and rainy afternoon.
However, there are steps you can take to minimize these winter challenges.
If you have plants in containers, check the drainage. A container that was perfect a few weeks ago may now be draining too slowly. It is disheartening to see a formerly healthy plant succumb to root rot from standing water. Remove any debris that may be preventing drainage, or move the container to a location shielded from the rain.
Inspect your irrigation system and be sure you are not overwatering. Watering schedules probably need to be adjusted to avoid flooding the lawn.
Plants suffering from overwatering can look deceptively similar to those suffering from under-watering. I have made this mistake before and spent a good deal of time angry with myself for drowning an already saturated plant. Investigate the cause of the damage you see before applying a remedy.
Do a detailed inspection of landscape plants, especially deciduous trees and shrubs. The lack of foliage will make any pests and damage much easier to locate and identify.
Some pests, such as scale, will soon be in their dormant, over-wintering, phase. During this stage they are more vulnerable to applications of horticultural oil. They are not breeding either, so you need not worry about missing their offspring when you spray.
Many plants have well-known pests, and an experienced gardener will recognize the culprit from the damage. The University of California's Integrated Pest Management website (http://ipm.ucanr.edu/) is a useful resource. You can enter the name of a plant and see a list of possible pests and diseases, often with photos. Should you see damage that you can't identify, take a photo and email it to the Master Gardener Help Desk (information below). You can also bring the damaged plant parts to the Help Desk and a Master Gardener will help you identify and manage the problem.
At this time of year, many people have unwanted visitors in their homes, and I don't mean the in-laws. The best way to manage rodents and ants in your home is to deny them access. Inspect the exterior of your home for possible entry points that may have developed over the summer.
Just because you haven't had problems in recent months does not guarantee future security. A small hole that pests ignored while they were comfortable outside can quickly become a superhighway during cold and wet weather. Fill holes with wire mesh or other strong materials that pests cannot chew or dig through.
If you are unable to seal a hole used by small insects, try blocking them with a line of diatomaceous earth. A powder made of ground silica, this product is safe for use around the home and has a high success rate. When it comes to your in-laws, however, I have no advice. You will have to figure that out for yourself.
Workshop: U. C. Master Gardeners of Napa County will host a workshop on “Rose Pruning” on Saturday, January 7, from 10 a.m. to noon, at University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Certified rosarian Lynne Andresen and other Master Gardener rose enthusiasts will demonstrate and explain proper pruning techniques and review rose types, common rose disorders and routine maintenance. Online registration (credit card only); Mail-in registration (check only or drop off cash payment).
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
Source: ucanr.edu