Deseret Nursery Perennial Farm

The watering mechanism by which most plants survive and thrive is to water deeply and less often. This is the most basic plant cultural technique, and it comprises the vast portion of the concept of xeriscaping.

Nearly all perennial plants if watered deeply once a week after they have been establisheed, will thrive.  Most will readily go two weeks and many three to four weeks. We consider a plant to be low water usage  at two weeks or longer. 

 After 3-4 weeks without moisture, the plant begins to show negative effects. Going beyond this time frame without watering is really not necessary in the effort to conserve water. Drought tolerant is just that, tolerance.  Going the distance does not mean that the plant is happy, it only means that it is tolerating the circumstances. With some moisture during the four week time frame, plants will be drought happy, and it will open up the garden to a vast array of plants, beauty and color

 Be it lawn, perennials, annuals, vegetables, shrubs and trees, plants do not like stay wet. They like to dry down between waterings. The watering of the home landscape, everyday, every other day or even three times per week, is by far the greatest cause of problems in the landscape in Utah. Whenever we are posed a question about a problem in the landscape by a customer, the first question we always ask them is how frequently do you water, and how long do you water?  Ninety percent of the time they will say everyday, or every other day for 10-15 minutes.

When the garden is watered frequently for 10-15 minutes, two things happen. First, the water only penetrates a few inches. The roots never grow deeper, because there is a lack of water deeper. The sun comes out, the soil dries out, the plants dry out, and so you water again in same manner.  The second scenario, is the soil is staying wet because of the frequent watering.  The roots lack the incentive to grow deep and healthy because they are getting the moisture they need in a short depth.  However, eventually some type of adversity comes along, and the plants take a hit because of the lack of a healthy root system.

When you water deeply less often, you drive the moisture down deep into the cool zone. Then, when you let the soil dry down, but not out between waterings, the roots go looking for the moisture, grow down into the cool zone, and feed off that moisture for days and weeks to come.  A thick layer of mulch around plants will help to conserve that moisture. This is the most important aspect of xeriscaping, and of gardening in general. 

When it comes to saving water, in the overall picture, it does not matter if you use overhead sprinklers or drip irrigation. Our feeling is if drip irrigation is your thing, then do it. If drip irrigation is not your thing, then don't do it. For the purposes of this discussion, we shall be making reference to overhead watering, assuming an average water pressure.

If you are growing perennials and annuals, and you have a lawn in the equation, it is best to water twice a week for 25-30 minutes.  If you are just watering perennials and bushes, then watering once a week for 30 minutes is sufficient. Nearly all perennials, if watered once a week, are happy.

By using low water usage perennials, you can water for 45 minutes every two weeks, while very xeric plants can be watered once a month for 60 minutes. If an automatic sprinkler system is employed, the water period can be broken up into two periods per watering, allowing for 15-30 minutes for the water to soak into the ground.  This is especially desirable on a hilly location. By watering deeper and for a greater length of time, and extending the time between waterings, is how you save water. As the overall amount you use decreases in significant percentages.

In small or out of the way plant areas, a soaker hose can be ideal to deeply water on 2-4 week interverals. We emphasize the need to soak the soil. Soaker hoses purchased from big box mart usually do not last long. We recommend purchasing a heavy duty soaker hose, which can readily be found online.