Drip irrigation is a highly effective way to water your plants and garden. But with any irrigation system, it’s important to strike the right balance between ensuring that your plants get enough water without wasting it or flooding the soil. So, how long should you run your drip irrigation system?
Trees that need a lot of water may need about 90 minutes twice a month and the water should reach a depth of 12”. A flower bed may need watering for 60 minutes twice a week. Watering time for drip irrigation depends on the emitters being used and the plants being watered.
Drip irrigation is a more targeted approach than traditional sprinklers, as the water is delivered directly to the base of the plants, reducing the risk of overwatering and promoting deeper root growth. Keep reading to learn how you can optimize your drip irrigation watering times below.
Benefits of Drip Irrigation
Before we dive into specific recommendations for different plants, let’s take a quick look at the benefits of drip irrigation:
- Water efficiency: Because drip irrigation delivers water directly to the plant’s roots, less water is lost to evaporation and runoff. Most drip systems are between 85% and 90% efficient. This makes it a more efficient way to water your garden, especially in dry or hot climates.
- Plant health: As mentioned, drip irrigation promotes deep root growth, which is essential for the overall health of your plants. Deep roots help plants to withstand drought conditions and recover more quickly from dry spells.
- Pest control: Using drip irrigation can also help to reduce the risk of certain pests and diseases. For example, wet leaves are more susceptible to fungal infections, and standing water can attract mosquitoes and other pests. By watering at the base of the plants, you reduce these risks.
Drip Irrigation Time for Different Plants
Now that we’ve covered the general benefits of drip irrigation, let’s look at how long you should run it for different kinds of plants:
- Annuals and perennials: Flowers typically require more frequent watering, as they have shallow root systems. As a general rule, aim to water these plants once or twice a week, depending on the weather and soil conditions. These flowers need approximately an inch of water or 5 gallons per square yard. You need to make the calculations for your situation, but if you’re using a dripline with ½ gallon/hour emitters, You’ll want to water your flowers about 60 minutes twice a week.
- Trees and shrubs: These plants have deeper root systems and are more drought-tolerant, so they can typically go longer between waterings. Aim to water these plants once or twice a month for about 90 minutes or when the water has reached over 12” deep, depending on the weather and soil conditions. When planning the irrigation for a tree make sure that your irrigation is on the outside half between the edge of the canopy and the trunk. Having the irrigation too close to the trunk will not lead to healthy root growth.
- Vegetables: Vegetables have different water needs depending on the type of plant and the stage of growth. For example, young seedlings and fast-growing plants like tomatoes and cucumbers may require more frequent watering, while root plants like potatoes and carrots can go longer between waterings. The time depends on the plants you plant but 60 minutes twice a week is a good starting point.
- Lawns: Drip irrigation is not typically used for lawns. Since a normal drip system can’t be completely buried without getting clogged, it has to be on top of the surface in the grass which would make the lawn unpleasant to walk on and could potentially be damaged during lawn maintenance or if anyone drives onto the grass. That said your grass needs about 1” of water per week, so if you’re irrigating with a correctly installed drip system you’ll want to run your system for about an hour every other day.
For a more exact calculation of watering times, check out this equation for calculating water time with drip irrigation from the Utah State University Forestry Extension.
How Does Soil Composition Affect Watering Times?
Different Soil Types have different watering requirements and will affect how long you need to water your beds.
Clay-like soils have very fine particles and tend to be very dense soil. This soil can take a long time to absorb the water, but it will stay moist for longer. Water will also spread out more in clay soils, which makes it so you can spread out that your emitters can be spaced further apart. Generally, you’ll need to water the area longer than in other soils, but not as often.
On the other end of the spectrum, there are sandy soils. This soil has larger particles and is less dense. This means that it doesn’t hold water very well, so it needs to be watered more frequently, but it doesn’t need to be watered for as long each time.
How Does Rain Affect Watering Times?
Getting rain is almost always a good thing for your garden and trees and means that you don’t have to run your system as long during the week. It also means that you can save water which is good for the environment and saves you money.
When it rains during the week, you’ll want to look up how much it rained and then you can subtract that from the amount you need to water during the week. Doing this will ensure that you are as efficient as possible and don’t overwater your plant.
Some irrigation systems, like Rainbird, have smart controllers which can connect to wifi and will adjust your watering schedule automatically based on rainfall.
If you’d like to upgrade your system, Sprinkler Master can help you find one that will work for you.
Hire a Professional
Drip irrigation is a highly efficient and effective way to water your plants and garden. By following the guidelines outlined above, you can ensure that your plants get the water they need to thrive.
If you have questions about drip irrigation or need help with sprinkler repair, don’t hesitate to contact Sprinkler Master. We’re here to help keep your irrigation system running smoothly and efficiently.
“Drip Irrigation.” URI HomeASyst, University of Rhode Island, 5 Aug. 2014, https://web.uri.edu/safewater/protecting-water-quality-at-home/sustainable-landscaping/drip-irrigation/.
Goldy, Ron. “Soil Type Influences Irrigation Strategy.” MSU Extension, Michigan State University, 21 Jan. 2022, https://www.canr.msu.edu/news/soil_type_influences_irrigation_strategy.
Kuhns, Mike. “Drip Irrigation for Trees.” Utah State University- Forestry Extension, Utah State University, https://forestry.usu.edu/trees-cities-towns/tree-care/drip-irrigation. “Tree Watering Guidelines.” Canopy, Canopy, 28 Oct. 2016, https://canopy.org/tree-info/caring-for-trees/trees-and-water/watering-guidelines/.