Lawn Fertilizers Explained

The finer points of applying fertilizer, organic or not, to the lawn are discussed.

To get a lawn to grow well, it must be fertilized. But if it's fertilized incorrectly, the fertilizer can do more harm than good. That's because lawn fertilizers are high in nitrogen, which can burn the grass if applied improperly.

fine textured sifted compost falls to grass roots

fine textured sifted compost falls to grass roots

Fine-textured sifted compost makes an excellent top dressing for an established lawn.

The three numbers (e.g., 10-10-10 or 20-5-10) on the front of any balanced fertilizer package stand for the percentage of nitrogen, phosphorous and potassium in the mix – always in that order. Nitrogen is needed for green leafy top growth, but if too much is applied or if it's applied on a hot summer day without watering it in, the lawn may be damaged.

To apply the proper amount of fertilizer to a turf area, use a broadcast or drop spreader. If there is an overlap when using a broadcast spreader, the lawn will acquire a green striped effect. If that's the case, consider a drop spreader, which makes it much easier to see where fertilizer has already been applied.

Several types of fertilizers are available for lawns. Starter fertilizer is designed for new lawns and has a little less nitrogen and some phosphorous to get the roots off to a good start. Some products are pure turf-grass fertilizers; others incorporate broadleaf weed killer. If there's only a small area to fertilize, mix dry fertilizer with water and apply the solution with a sprayer. This method of fertilizing is called foliar feeding.

Always wash out the sprayer over turf or soil – never over concrete. The fertilizer or herbicide may run off the concrete area and into storm drains, which lead directly to creeks, bays and rivers.

Another option is to feed the lawn with a natural fertilizer – for example, manure tea. To make it, place steer or chicken manure in cheesecloth or an old pair of pantyhose, and soak it overnight in a 5-gallon bucket filled with water. Fill a portable sprayer, watering can or hose-end applicator with the solution, and apply it to the lawn.

Another fine lawn amendment is fine-textured sifted compost. The fine texture allows the particles to fall between the blades of grass and reach the crowns or stolons and roots. Put sifted compost into the drop spreader and apply it to an established lawn as a tonic. Top dressing with compost improves the soil and nourishes the grass at the same time.

Another type of organic lawn fertilizer is Milorganite, made from sterilized sewage sludge. Although it contains only 6 percent nitrogen and 2 percent phosphorous, it works well as a lawn fertilizer but not as quickly as higher-nitrogen products and with much less risk of burning the turf.

Don't overlook the old standby, fish emulsion. Use a hose-end sprayer to apply it to the lawn. Fish emulsion has a distinctive odor.

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