Watering in the winter can be a bit tricky here in Los Angeles. Since temperatures are cooler and most plants are dormant or semi-dormant, the soil needs to be watered less frequently than in warmer months even when there is no rain. Consider that when it rains there is a light to medium spattering of water onto the surface of the ground over hours of time – as compared with the heavy deluge of sprinklers splashed out for minutes at a time. As a result, water has a chance to penetrate more deeply over a longer period with rain. Even when the winds blow and dry out the surface, the lower layers remain moist in the winter far longer than in the warmer, dry months.
To imitate nature’s watering, it is best to water several times with small amounts of water early in the morning to minimize evaporation. On Los Angeles county hillsides, this is especially true as any quantity of water is likely to simply run off rather than sink in. With lawns, multiple short waterings in succession is likely to allow the water to penetrate soil layers and encourage the roots to burrow down in order to follow the moisture. Although many landscapers suggest watering once in the morning and once in the afternoon, this practice is likely to encourage roots to stay on the surface, leaving them vulnerable to any radical weather change, insect infestation or soil damage Grouped water applications work well on a daily basis in the hottest of seasons. In the winter, if we have a good rain, we can often go up to two weeks without additional water. Even during this prolonged winter dry spell, watering daily or even every few days at this time of year will waste water. Try using the multiple watering-in-succession habit every 5 to 7 days.
Most plants are dormant and use little water in the winter. California natives, some imported drought tolerant plants, vegetables and winter annuals are the exception. They need water at this time of year – though the natives and drought-tolerants are more forgiving than the vegetables and annuals. If it continues dry, watering every few days for vegetables and annuals, and once a week with the above plan should keep all your garden denizens happy. It should also keep your water bill reasonable. Watering wisely is likely to become ever more important as this area continues to grow. Even in a year of good rainfall, I expect the cost of water is likely to grow progressively higher over the Los Angeles area. Overbuilding this fragile environment may cause a serious water shortage in future years. Consider planting your water-wise plants now so they establish themselves in coming years, and try out some water-saving programs and irrigation systems on the rest of the garden. We can always find somewhere else to spend any money saved!
Related article:
Smart Array Irrigation Controllers
