As the dry season begins on the Olympic Peninsula, it’s a good time for gardeners to start thinking seriously about water conservation. While the memory of mid-winter rain might still be fresh, the region’s climate tells a more complex story.

The Olympic rain shadow creates dramatic differences in rainfall across the Peninsula. While the far west can receive well over 100 inches of rain annually, Sequim, sheltered in the rain shadow, averages just 16 inches. As summer sets in and rainfall dwindles, thoughtful water use becomes essential for keeping gardens healthy and sustainable.

After plentiful sun and rich soil, water is the third most essential element in the garden. Yet, it is often the least considered. If vegetable gardens are water stressed, a decrease in vitality and yield may result. Landscape plants that are chronically over- or under-watered perform poorly and are more susceptible to diseases, pests and failure.

To conserve water and to protect the hard work and investment put into a garden, developing a water plan is a smart idea. The plan doesn’t have to be expensive; it can be as simple as attaching a manual timer to a soaker hose. The importance of a timer for any watering method truly can’t be stressed enough.

A few things to keep in mind for summer watering on the North Olympic Peninsula:

• Most plants, even those labeled as drought-tolerant, will need supplemental water during the dry summer months.

• Grouping plants with similar water needs (a practice called hydrozoning) makes watering more efficient and effective.

• Frequent, shallow watering encourages shallow roots, which makes plants more vulnerable to heat stress. Applying water thoroughly is the key to proper watering.

• Watering early in the morning is best as it reduces evaporation and helps prevent disease.

• Overwatering can be just as harmful as under-watering. A timer is a valuable tool to help prevent costly plant and property damage from unattended irrigation.

For any watering plan, it’s helpful to distinguish certain areas of your garden as distinct from other areas based on water needs. For example, a vegetable garden will have very different requirements than a shrub bed. To avoid frustration, each area can be approached individually, as its own manageable project. Different areas may call for different solutions with varying levels of complexity.

Generally, established trees, shrubs, lawns and ground covers only need to be irrigated thoroughly once a week during the dry period (and some established plants might need even less than that). For these areas, a soaker hose or even a sprinkler (on a timer) might be best. Keep in mind that anything newly planted, even those labeled as drought resistant, will need regular water for the first year.

In-ground vegetable gardens and ornamental plantings should be considered separately from raised beds and containers. They typically require less frequent watering because native soil in the ground tends to retain moisture better and allows roots to grow deeper, accessing water stored below the surface.

Containers and raised beds often have faster-draining soil mixes and increased exposure so they tend to dry out more quickly. As a result, potted plants and raised planters usually need more frequent attention, sometimes daily, to maintain consistent moisture levels, especially during hot or windy conditions.

For areas that need frequent watering, there are many good reasons to consider setting up a simple drip system. A drip system can be 90-95% more efficient as compared to hand watering. They save time and labor, even operating automatically while you are on vacation.

A drip system will direct the water only to the root zone of a plant which can conserve water and reduce weeds and disease, making for healthier plants. Using an automatic timer helps provide consistent and adequate moisture during the dry season.

As a DIY project, simple drip irrigation systems are relatively easy to install after a brief learning curve. For beginners, kits are available for small garden areas. There are also plenty of helpful resources and YouTube presentations that help the novice.

That said, more extensive systems can be complex and physically demanding to set up, so hiring an irrigation specialist may be the best option. If you do work with a contractor, be sure to stay involved in the installation and take time to understand how the system works. This knowledge will make future DIY repairs quicker, easier and more affordable.

For more watering advice, see Washington State University’s “Watering Home Gardens and Landscape Plants” (EB1090) available for free at http://pubs.cahnrs.wsu.edu/publications/pubs/eb1090 or the website on Drip Irrigation Techniques and general information (https://foodsystems.wsu.edu/crops/irrigation/).

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Susan Kalmar is a WSU Clallam County Master Gardener.