How to Water-In Fertilizer With Rain

adding fertilizer to garden
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Fertilize your lawn properly, and you’ll be on your way to a healthy, dense stand of turf that maintains a deep green color and gives weeds a run for their money. Nitrogen is every lawn’s most important ingredient, and each type of grass demands different amounts to display peak growth and performance. 


All fertilizers should be watered in and the best way to do it is naturally, with rain. Try to time the application of fertilizers to just before an expected rainfall of at least 1/4 inch.

It can be difficult to achieve adequate coverage and the proper amount of water with lawn sprinklers. Applying fertilizer before rain provides insurance that the product will be washed into the soil and become available to the plant.

An irrigation system can be used to water-in fertilizer but nothing beats the even coverage and natural qualities of a prolonged, steady rain.

Of course, if heavy rains are expected, it's best to not fertilize to avoid washouts and leaching.

Using a Broadcast or Rotary Spreader

A broadcast or rotary spreader works well when you’re fertilizing larger lawn areas. Apply fertilizer around the edge of the lawn first, and then start to move back and forth across in an orderly pattern. Overlap application strips slightly to ensure that you cover the whole lawn evenly with fertilizer.

Using a Drop Spreader

Choose a drop spreader for controlled fertilizer distribution. Overlap slightly on each pass to ensure you have adequate coverage. You’ll typically pay more for a drop spreader, but if you’re tending a typical suburban-size lawn, it’s worth the investment. Water it in well, and do so again a few days later to help move that nitrogen down through the soil and out of the lawn’s root zone.

Using a Handheld Broadcast Spreader

A handheld broadcast spreader works well for fertilizing small lawn areas. Walk evenly and slowly, and be sure to overlap distribution patterns slightly with each pass. A small spreader like this also works really well when you have shady areas in your lawn that require a different fertilizer rate than the sunny sections. Some fertilizers combine a herbicide with the lawn food. These products are sold as weed-and-feed lawn care products and are applied using a lawn spreader.


Grasscycling refers to letting grass clippings lie on the lawn after cutting. These clippings can provide up to 25 percent of your lawn’s fertilizer needs, saving you time and money. One hundred pounds of lawn clippings can yield up to three to four pounds of nitrogen. You don’t need a specialized mulching mower to grasscycle, although you might want to replace your current mower blade with a mulching blade, which cuts grass into smaller pieces that decompose more quickly.

Soil Aeration

If you plan to aerate your lawn, follow up that task with fertilizing. Lawns benefit from soil aeration, which creates literal holes in the soil and exposes the root zone of grass plants. These holes allow water, fertilizer, and air direct access to the roots of the grass.