Watering a hill can be a little bit of a challenge. With the force of gravity pulling water down the hill, plants near the top of the hill can be left with not enough water and plants at the bottom can receive too much. Gardeners need to be able to control runoff to ensure that plants get the water they need. Read on for ideas on how you can grow successfully on a slope.
Irrigation for Slopes
When watering plants on a slope, being able to control runoff is going to be a gardener’s most challenging obstacle, especially if the soil doesn’t drain well. Runoff is water that does not get absorbed into the soil, but instead flows to an area where water is collected (often the bottom of a hill). To be able to prevent runoff you have to make sure that the soil has time to absorb the water. There are a few options to make sure your slope can absorb water and the option you pick will have to do with the types of plants that are growing on the hill.
Watering a Hill of Grass
If your hill is mostly composed of grass then sprinklers might be your best option. On a slope you can’t use the sprinklers the same way that you use them on a flatter surface. For example, your sprinklers need to be on a timed system that runs and then shuts off at shorter intervals. This is important because you have to give the soil time to absorb the water.
If it only takes 20 minutes of watering before water starts to run down the hill, then your timer needs to shutoff after 20 minutes. However if your plants need an hour of watering then the timer needs to be able to kick back on after a certain amount of time to continue watering.
Another option to consider is getting a sprinkler system that delivers water at a lower rate than other conventional sprinklers. There are several companies that design sprinklers to dispense water at a lower rate specifically for the purpose of watering hills.
Watering a Hill of Groundcover, Shrubs, and Trees
Drip irrigation is the probably the best option for watering a hillside that features plants besides grass. You can place the drip emitters by the plants you need to water and not waste water on empty areas. With drip irrigation you can also better control the amount of water you give each individual plant. For example, if you have a shrub that requires more water than surrounding plants you can just place more drip emitters around that specific shrub.
For drip irrigation you won’t need to use a timer that shuts on and shuts off. Because a drip system irrigates so slowly the soil should have plenty of time to absorb the water. If you do want a timer for drip irrigation you might want to pick one that can stay on for over three hours, especially if you want less frequent but deeper soakings.