How to Use Fertilizer

Grass nutrients are the key to growing a beautiful and lush lawn. This guide from Briggs & Stratton will help you choose the best fertilizer, set a fertilizer schedule and finally learn how to fertilize your lawn.

How to Read a Fertilizer Label

When you fertilize your lawn, you are applying three key nutrients for plant growth: 
• Nitrogen Fertilizer (first number)
• Phosphorus Fertilizer (second number)
• Potassium Fertilizer (third number)
These fertilizer nutrients will be listed as three numbers on the bag, and always in the same order 20-5-10. This means that there are four parts nitrogen (first number) to one part phosphorus (second number) to two parts potassium (third number).

For an actively growing lawn, the most important fertilizing nutrient is nitrogen. Look for the words "slow release nitrogen" on the fertilizer bag. This type of nitrogen will be released over a period of weeks to continually feed your lawn. Also, you have less chance of burning and damaging your lawn with slow release nitrogen. 

For a new lawn or if you are seeding bare spots, use a starter fertilizer which contains a higher percentage by weight of phosphorous to help develop the seedling roots. 

When to Fertilize

Your lawn should be fertilized at least three times a year. It’s important to only feed your lawn when it’s actively growing, never during a drought. Otherwise it’s safe to set your fertilizer schedule around the holidays:
• Memorial Day
• July 4th
• Labor Day
In the South, where you have warm season grasses, you can slip in an extra feeding in early August, especially if you are watering your lawn. In the northern half of the country, where you have cool season grasses, apply a fourth application in November to have a beautiful lawn the following spring.
During a drought, decrease or stop using fertilizers to reduce the amount of lawn nutrients your grass receives. This will cause the grass to grow slower and eventually go dormant, which is best for a lawn during a drought. That also means watering the lawn less. Reintroduce the fertilization schedule during cooler, wetter months in the fall.

How to Fertilize

Now that you know the best fertilizer to use and how to set a fertilizing schedule, it’s time to learn how to fertilize the lawn: 
• At your local garden center, buy a high quality fertilizer spreader.
• Apply fertilizer on freshly mowed grass when it isn’t windy and there is a light dew still on the ground. This will help the fertilizer spreader evenly distribute, leaving visible tracks of where the fertilizer has been applied.
• Most fertilizer rotary spreaders cover a swatch of grass around 6 to 8 feet wide. For big yards, set surveyor flags to provide reference points. 
• To apply fertilizer evenly, cut the amount used in the rotary spreader in half. Then apply in opposite walking directions. This trick, used by the pros, is the biggest reason why you don't see streaks caused by too much fertilizer in golf course grass or baseball fields.
• For even fertilizer distribution, start walking before turning on the rotary spreader and shut it off before you stop walking. 
• Be sure to wash the fertilizer spreader after use. Because of its salt properties, most fertilizer is very corrosive.
Water the lawn. Improve the fertilizer's efficiency by watering the lawn soon after an application. Better yet, try to apply fertilizer just before it rains.

The Dangers of Over-Fertilization

Besides having to mow the lawn more frequently, there are negative consequences to over-fertilization:
• When your lawn grows quickly after over-fertilizing, it will be more important than ever to follow the one-third rule. Never cut more than a third of the leaf blade off during any single mowing, when using a push mower or riding mower. If scalping occurs, your lawn will be very susceptible to weeds.
• Turfgrass diseases, such as brown patch and pythium: Both of these diseases are fungi born and occur in warm, moist and over-fertilized conditions and require fungicide to control them.
• In extreme over fertilization, five to 10 times the recommended application rate, the grass will turn a straw or tan color and the leaf blades will burn from the tip down. If this occurs, the existing grass cannot be salvaged, but new grass will eventually replace the bleached or burned grass. 

It’s easy to see how fertilizing provides the lawn nutrients needed to promote growing thick & green grass while eliminating weeds and fending off disease. In combination with Lawn Care Tips and Lawn Watering, you will have the most beautiful grass in the neighborhood. 

>> For further tips, visit the Briggs & Stratton Dealer in your neighborhood today!


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