How to Properly Use Fertilizer
Fertilizing your lawn or garden seems like a no brainer: you just throw it out and the fertilizer works, right? Actually, fertilizing is a bit more complicated. For example, there is a difference between broadcasting fertilizer and incorporating it into the soil. When you broadcast the fertilizer, you spread it on the surface of the plants and soil with a spreader. This is usually done with granular fertilizer. After broadcasting it, you water the lawn or area where the fertilizer was spread. This dissolves the granules and spread the fertilizer down to the root zone where the plants can absorb it.
Broadcasting fertilizer is usually done with a lawn or pasture where there are existing plants that cover the soil. In a garden or flower bed, fertilizer is usually spread before the plants are planted to prepare the soil for them. In this case, the fertilizer is spread over the area and then worked into the soil with a rake until it is evenly distributed throughout the area. Then the seeds or plants are planted and the area is watered. The granules dissolve and fertilize the seeds or plants.
Once a garden or flower bed is planted, fertilizer cannot be worked into the soil directly around the plants without disturbing their roots. In this case, it is placed in the rows or spaces besides the plants and worked into the soil there. This is called side dressing with fertilizer. Again, the fertilizer must be worked into the soil and watered in to fertilize the plants.
Sometimes water soluble fertilizer is sprayed as a solution directly on the plant’s leaves. This is called a foliar spray. Generally, this is done to remedy a specific deficiency in the plant. For example, zinc is often sprayed on pecan trees to prevent or treat a zinc deficiency. Iron is another common foliar spray. It is important to spray the trees or plants as directed so that they can take the nutrient up with their leaves.
Finally, there is liquid fertilizer that is applied to the tree or plant when watering. Sometimes this is done by adding it to the water system at the faucet using a siphon, or by watering individual plants with it in lieu of some of the water it they would normally receive. This type of fertilization is most common with houseplants or with big industrial operations growing too many plants to side dress or fertilize individually.
To summarize, broadcast fertilizer is spread on lawns or fields where plants cover the soil. In gardens, fertilizer is usually worked into the soil prior to planting. After plants have started growing, fertilizer may be spread beside the plants to avoid disturbing their roots while still providing the needed nutrients. All of these fertilizers need to be watered in to function.
Foliar fertilizers are applied to the leaves and stems of plants to allow the nutrients to be absorbed directly by the leaves. Liquid fertilizer can be applied to the roots of the plants through drip irrigation or by using it instead of water for a portion of the plant’s needed liquid while it is growing.
Remember to follow label directions and never apply more fertilizer than recommended. Just as in most things, too much fertilizer can be as harmful as not enough fertilizier.