What's the Difference Between Natural and Synthetic Fertilizers?

A gloved hand holds fertilizer pellets
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Fertilizing is important in gardening. Whether you're growing vegetables and want a good yield, enjoy seeing maximum blooms in your beds, or you just want healthy plants, fertilizer plays a key role in achieving your gardening goals. Fertilizer provides the key nutrients plants need to grow, thrive, and produce. What's in Fertilizers? There are three main nutrients that all basic fertilizers provide: nitrogen, phosphorous, and potassium. Nitrogen is important for growth, but too much of it can cause plants to become deficient in other nutrients. Phosphorus stimulates the growth of roots and seeds, and sets the buds and flowers. Potassium helps plants process the food they make. In lesser amounts, plants also need calcium, magnesium, and sulfur. Different types of fertilizers have these nutrients in varying ratios. Synthetic Fertilizers A synthetic fertilizer is one that is made from chemicals developed in a fertilizer manufacturing plant. These fertilizers are made from chemicals, including ammonia, natural gas, nitrogen from the atmosphere, phosphate minerals, and potash. You can buy this kind of fertilizer in any garden store or nursery, and you'll find it in a variety of ratios, typically with all three main nutrients. For instance, a 10-10-10 N-P-K fertilizer contains ten percent each of nitrogen (N), phosphorous (P), and potassium (K). Fertilizers for Organic Gardening Organic gardeners prefer fertilizers that are whole substances and mixtures derived from plants and animals. Examples include manure, bone meal, and fish meal. While synthetic fertilizers contain concentrated amounts of a few nutrients, these fertilizers often have a wider variety of nutrients in lower concentrations. Why Synthetic Isn't the Best Choice There are several reasons a gardener may want to avoid synthetic fertilizers, which offer an intense blast of nutrients. Plants will take up the nutrients from synthetic fertilizers very quickly, but it is possible to overdo it and damage them. The fertilizers used by organic gardeners are usually more varied in their content, which slows nutrient absorption and encourages microbe development. Synthetic fertilizers pose a real problem for the microbes, which may actually be depleted as a result of using synthetic fertilizer. Synthetic fertilizers can also be damaging to the environment. They are often highly water soluble and leach into groundwater, streams, and ponds. Once there, they stimulate plant growth, causing an overgrowth of algae and other green plants. The OMRI Listed® Option Organic gardeners have an alternative to using synthetic fertilizers. By looking for products with the OMRI Listed® seal, gardeners can rest assured they're buying supplies that are compliant for use in organic gardening. This seal indicates a successful review by the Organic Materials Review Institute (OMRI), which inspects these products to make sure they meet organic standards developed by the USDA National Organic Program. Using OMRI Listed® materials is one step toward allowing a farm or processing facility to sell, label and represent their products as organic. Importance of OMRI Listed® Nutrients for Hydroponic Gardening Hydroponic gardening, or growing plants without soil, can still provide a good yield. That said, getting the right balance of nutrients is even more important when gardening without soil. For a hydroponic garden, liquid fertilizers are used to deliver the nutrients the plants need. The easiest way to get your hydroponics their nutrients is to look for kits and fertilizers specifically designed for creating and maintaining a hydroponic growing medium. When choosing fertilizers for your organic garden, whether hydroponic or in the soil, consider the important differences between OMRI Listed® and synthetic options. Companies such as Safer® Brand, which has a line of OMRI Listed® fertilizers, can help you choose the right products for your organic garden. You can even order online and get your fertilizers shipped directly to your home or business. And for those of you trying your hand at liquid fertilizers for the first time, you can even sample their full nutrient line without having to make a full-scale investment. The Safer® Brand Nutrient Kit provides samples of all the fertilizers necessary to grow one plant from start to finish.

Mary Ellen Ellis

Mary Ellen Ellis has been gardening for over 20 years. With degrees in Chemistry and Biology, Mary Ellen's specialties are flowers, native plants, and herbs.