A soaker hose is a porous device that delivers water directly into the soil along its entire length, distinguishing it from a sprinkler that sprays water overhead. This design allows moisture to “weep” slowly and consistently, minimizing water lost to evaporation and surface runoff. The purpose of this method is to achieve deep, infrequent watering, which encourages plants to develop extensive, drought-resistant root systems.
Determining the Initial Watering Duration
The initial duration for running a soaker hose is set by aiming to deliver the guideline of one inch of water to the garden each week. A general starting point for an average garden with loam soil is a run time between 30 and 90 minutes, two to three times per week. This range allows water to soak deeply without causing surface runoff. Plants with shallow root systems, such as annual flowers and vegetables, require moisture penetration of about six to eight inches. Deeper-rooted plants, including established shrubs and trees, benefit from a longer, sustained soak to drive the moisture down to 10 to 18 inches. This initial duration is simply a test period, as the actual time needed depends heavily on the surrounding environment and the physical limitations of the equipment. Adjust the frequency in response to weather conditions, as hot, dry periods necessitate more frequent watering than cooler weeks.
How Soil Type and Climate Affect Run Time
The composition of the soil is a factor in how long a soaker hose needs to run to achieve adequate depth. Sandy soils drain water quickly, requiring shorter, more frequent watering sessions to keep the root zone consistently moist. Conversely, heavy clay soils absorb water slowly. Watering clay soil requires a much longer run time at a slow pace to allow for deep penetration and prevent surface runoff. If water is applied too quickly to clay, it flows away before it can soak in. Loam soil, a balanced mix of sand, silt, and clay, absorbs water at a moderate rate. Climate also dictates adjustments because high temperatures, low humidity, and wind increase evapotranspiration. Evapotranspiration is the process where water is lost from the soil surface and the plants’ leaves. During periods of high heat and wind, the run time or frequency must be increased to compensate for the accelerated rate of moisture loss.
Verifying Water Penetration: The Soak Test
Relying solely on a timer is insufficient; the only reliable way to determine if watering is effective is to verify the depth of the soak using the “Soak Test.” The test involves running the soaker hose for the initial determined duration, such as 60 minutes, and then immediately checking the soil moisture. To perform the check, use a trowel or a small garden spade to dig a hole six to twelve inches deep near the hose line and the base of a plant. The goal is to physically observe the depth to which the soil has been saturated. For most garden vegetables and annuals, the target depth of moist soil should be at least six inches. If the soil is only moist three or four inches down, the run time must be increased during the next session. If the soil is saturated deeper than necessary, or if water is pooling on the surface, the run time can be shortened or the water flow reduced. Repeating this test a few times ensures that the established run time consistently meets the specific root zone needs of the plants.
The Role of Water Pressure and Hose Length
Soaker hoses are engineered to operate at low water pressure to facilitate the slow, weeping action. The optimal pressure for most systems is between 10 and 20 pounds per square inch (PSI). Higher pressure can cause the hose to spray rather than seep, wasting water and potentially damaging the hose structure. For this reason, a pressure regulator is often necessary to attach to the spigot to ensure the water flow is reduced to the ideal range. The physical length of the hose also affects water distribution and run time. Soaker hoses lose pressure over distance, meaning the end of a long run will emit less water than the beginning. Most manufacturers suggest a maximum effective length of 100 feet for a single run to maintain uniform water delivery. If the hose length exceeds this, the run time must be increased, or the system should be split into multiple shorter runs to ensure consistent coverage.