Fertilizers must often be used to help the soil reach its peak potential. There are 13 soil nutrients that are needed for a successful garden. Not all of those are always present, but fortunately there's a way to fix deficiencies. Fertilizers are often the answer to fixing any kind of nutrient deficiencies, and it's important to know what you need and what fertilizers can supply it.
Animal manure is one of the ultimate organic fertilizers, and and home gardeners and landscapers often overlook it. Manure from cows and horses is especially good for soils that are lacking in phosphorus. Phosphorus is released into the soil as the manure slowly decays, acting as a time-release additive. It's also good for areas of land that have irrigation systems, as manure has a unique property that increases the rate as which water passes through the soil.
Manure does have its drawbacks, though. Those include a possibility to cause problems in the garden because of weeds and foreign matter not digested by the animal the manure came from. If applied incorrectly, manure can get on fruits and vegetables destined for human consumption and cause bacterial infections.
Slow-release fertilizers have the advantage of being able to be applied once and last for an entire season. These fertilizers are made of hard material that dissolves slowly in the ground, releasing the nutrients a little bit at a time.
The fertilizer is coated in a resin that regulates how fast the nutrients are released and contains nitrogen in a form that is easily processed by plants.
The drawback to slow-release fertilizers is that if they are applied too late in the season, they may keep the plant's growing season going too far into the cold weather and damage the plant.
Complete fertilizer is a broadly used name that can describe both organic and inorganic compounds.
What makes a fertilizer complete is that it contains each of the three main nutrients needed by all plants: nitrogen, phosphorus and potassium. Complete fertilizers only need to be used when soil tests show that all three are missing.
Chemical fertilizers are those that are mixed by man. They are often the most affordable of fertilizers and among the most commonly used today.
Quickly absorbed into the soil and therefore into the plant, chemical fertilizers are often diluted to the proper strength. Failing to consider the strength of the fertilizer can end in burning or otherwise injuring the plants. The chemicals must be applied evenly and carefully to minimize this risk.