Fertilizing Your Landscape


There are many factors to consider before fertilizing your landscape. The type of landscape, the type of irrigation system, the season and even the soil type will affect which fertilizer you use and how much.

Type of Landscape

Grasses and green lush landscapes use a lot more fertilizer than native or xeric plants. Most landscapes in Las Cruces are xeric and use less fertilizer.  Native landscapes will generally need less fertilizer because they use less water.

Irrigation Systems and Fertilizing

There are all kinds of irrigation system installed in Las Cruces.  Each type changes how you fertilize. Your irrigation system affects the way that you fertilize your plants and lawn.

Many of the systems are drip or slow watering systems. They put water very slowly and let the water penetrate the root zone. Plants watered by these systems work better with liquid fertilizers.

Sprinkler systems that drop water on top of the landscape use solid fertilizers that dissolve when it becomes wet.  It then moves into the soil with the water.

Season and Fertilization

Temperature plays a major role on your landscape reaction to fertilizers.  When it is warm, plants grow more,  plants need more water and fertilizer is used up faster. Too little fertilizer causes growth to slow and may cause discoloration of the leaves.

Warmer temperatures make it easier to burn the plants. Fertilizer is salt and will burn foliage if too much is applied. New landscapes are easier to damage and requires less fertilizer.

During spring roots start to develop even before leaves start growing. Fertilizing during this time will give a jump start for your landscape. This gives the plants a chance to develop roots with less chance of burning.

Plants stop using fertilizer as much in the fall and winter. In some ways it helps to not fertilize when it starts cooling. Not fertilizing in fall and winter slows growth and hardens off the plants, making them less likely to freeze.

For the first year use a limited amount of fertilizer.  Then the next spring select a fertilizer with all three major nutrients.

Know What You Buy

When buying fertilizer look at the three numbers on the package. (16-8-8 for example) These show the amounts of the three major nutrients. This labeling is required by law. If the fertilizer has other nutrients available it will also be listed here. You see iron and zinc in many of our fertilizers because they are often in short supply in Las Cruces soils.

The first number refers to the amount of nitrogen available. In the example, the “16” says that 16 percent of the fertilizer is nitrogen. Nitrogen promotes leaf growth. It is the most needed nutrient in this area. Soils in Las Cruces usually are low in nitrogen.

The source of the nitrogen will also be on the label. Urea is a good source for cheap nitrogen. It is also high salts and can burn plants and lawn quickly. This works great for grasses if you can get enough water on quickly.

Ammonium sulfate or nitrate burns less and you see the results faster. It also does not make the grass grow as fast, so you have to mow it less.

Both of these are solid fertilizers.

The next two numbers (8-8 in the 16-8-8 example) shows the available phosphorus and potassium.  These help cell development and promote fruit and strength of the plant. These nutrients are required only once a year. They stay put in the soil and do not move out like nitrogen.

Nurseries sell fertilizer with all three nutrients year round. But you only need to apply these once in the spring. Applying these more than once a year wastes your money and hurts the environment.

Liquid fertilizer follows the same rules for labels. It usually does not burn plants as easily and can be sprayed on the leaves. These work best for drip systems.

Liquid fertilizer can be sprayed on the foliage and will be absorbed into the plant very quickly.  Liquid fertilizer  cost more, but is easy to put on and has less negative effect on the environment.

Soil and Fertilizer

The type of soil affects how you fertilize. Sandy or rocky soils use more fertilizer than valley soils or clay soils.

Plants  grown in clay of valley soils will develop larger root systems because they have more water available. They will have less trouble with over fertilization.

Conversely, plants in sandy soil will have less root development and can burn easier. It is important to water extra when you fertilize in sandy soils.

If you have questions about which fertilizer to use call Circle R Landscaping. We will help you out.