Why Are There Brown Spots and Uneven Growth In My Landscape?

Improper Irrigation Causing Brown Spots
There are many causes for unsightly brown spots  and uneven plant growth. In this article, we’re only going to look at your automated irrigation system and the ways it may be involved. Your system may be causing these problems due to damaged or clogged sprinkler heads, improper installation, or head placement. You should check all of these possibilities and fix them if they exist. Sometimes, poor sprinkler coverage doesn’t show until severe hot, dry weather when your lawn is not receiving any supplemental water from rainfall. You can also discover problem areas with new plantings because they haven’t developed mature root systems and more clearly show the effects of under-watering.

Incorrect Sprinkler Height

One of the most common causes of irrigation system-related brown spots and poor plant growth is incorrect sprinkler height. This can also lead to damage of your system. When looking at sprinkler height problems, they can be either too low, too high, or there may have been significant plant growth or natural change in soil levels.

Too Low

Sprinkler heads that are too low can’t rise far enough above the ground or turf level to adequately water the surrounding area. It’s also possible that they can’t rise above the level of the plants growing near them. In either case, coverage gaps and flooding around the sprinkler head results, and you end up with uneven plant growth and brown spots in your landscape. In addition, dirt can get in the components of the sprinkler head causing mechanism failures and retraction problems.

Too High

When sprinkler heads are installed too high they can cause trip hazards and risk to lawnmowers and other landscaping equipment. Of course, the heads themselves can be damaged by people tripping over them or by being run over by equipment. If you inadvertently damage a sprinkler head, that zone may not be adequately watered, resulting in brown patches and uneven plant growth.

The simplest way to fix a sprinkler head that was installed too high is to dig around the head, disconnect it, and then reconnect it using a swing joint or Funny Pipe which you can position to the correct height.

Plant Growth

Your sprinkler heads may be installed at the perfect height, however the plants they’ve been watering may have grown since the system was installed. For example, sprinkler heads near shrubs might need to be adjusted as the shrubs grow. The same applies to sprinkler heads watering groundcover plants.

Ground Level Changes may be installed at the exact

Ground levels raise or lower as time passes. Rain and flooding can wash away soil, lowering the ground level and decomposing grass clippings, leaf matter, and other organic materials can build up the ground level. These natural changes can raise or lower your sprinkler head height. The easiest way to fix this is to dig out the head, disconnect it, and reconnect it using a swing joint or Funny Pipe.

You should make a habit of periodically checking sprinkler heights to prevent uneven plant growth, brown spots, and potential injury to people or equipment.

Helpful Tip

It’s best to trim the grass around your sprinkler heads by hand, rather than using a weed eater. However, if that’s not possible, make sure you clean up all of the grass clippings around the sprinkler heads to prevent build-up. Never dig around the heads unless you removing them for repairs.

Clogged Sprinkler Nozzles

Dirt and debris can work their way into the sprinkler heads. When that happens, it can prevent the sprinkler heads from spraying properly which causes gaps in the spray pattern and leaves you with brown patches in your lawn.

The best way to diagnose lawn sprinkler heads is to watch the system while it’s watering. You can observe each sprinkler head to determine if it’s broken, being blocked by overgrown plants, or if there is an internal disruption of the spray pattern.

Note: Don’t attempt to remove the sprinkler nozzle by prying with a screwdriver! Sprinkler heads are easy to remove, but you must be careful when you’re doing it to prevent damage.

Incorrect Sprinkler Head Spacing

Another way your irrigation system can cause brown spots is through improper sprinkler head spacing. The system may be operating at peak efficiency; however, there may be gaps in the spray pattern. It’s important to plan proper spacing when you’re designing your system, as it’s much easier to place the heads correctly at installation then it is to move the master.

Proper sprinkler placement requires the spray from one sprinkler head to reach the next closest sprinkler head and so on. This is called “head-to-head” coverage it ensures optimum watering overlap which compensates for any spray pattern imperfections.