How do I Choose the Best Starter Fertilizer?

Starter fertilizer is a liquid or solid that is placed near seeds or seedlings to help begin and establish root growth. The primary difference with starter fertilizer is a higher concentration of phosphorus as compared to non-starter fertilizer. Thus, ensuring the proper mix of nitrogen, phosphorus, and potassium, commonly designated as N-P-K, is the most important consideration. A quality fertilizer will also condition the soil for root growth and water retention. Using an organic starter fertilizer or the choice of a solid or liquid variety will depend upon your needs and preference.

Fertilizers available to consumers use the N-P-K designation to label the percentages of nutrients it contains per application pound (0.45 kg). For example, a 20 pound (9.07 kg) application of a 5-10-5 fertilizer designation would indicate that 1 pound (0.45 kg) of nitrogen, 2 pounds (0.9 kg) of phosphorus, and 1 pound (0.45 kg) of potassium would be added during of the application. Application rates are usually designated as pounds per 1,000 square feet (92.9 square meters).

Phosphorus is the key element needed to establish root growth as a seed begins to sprout. The benefits of using a starter fertilizer with an ideal amount of phosphorus are many. The phosphorus in the soil aids new roots by causing them to grow quickly. It also enhances a plant's ability to flower. There is debate about the need for phosphorus if soil tests indicate adequate levels are already present, but most starter fertilizers contain a higher concentration of phosphorus to make it readily accessible to new roots.

Nitrogen is used to increase a plant's ability to produce chlorophyll. Chlorophyll allows plants to use sunlight and change carbon dioxide and water into glucose and oxygen. Too much nitrogen can be harmful to tender plants, so many manufactures use slow-release nitrogen to prevent overwhelming seedlings.

Potassium is the third ingredient in the N-P-K designation. It is used to stave off the effects of cold weather and fight off disease. It also contributes to the process of photosynthesis.

Choosing a liquid or solid starter fertilizer is mainly a matter of convenience. Using a liquid fertilizer allows you to have a little more application control, whereas solid starter fertilizer may be more difficult to apply evenly. Too much unevenly applied fertilizer can damage plants.

Organic starter fertilizers contain different ingredients than do non-organic varieties. The organic varieties typically contain less phosphorus because of potential health and environmental concerns. Should a soil test indicate phosphorus is needed, bone meal is a good source available in many organic fertilizers available on the market. Organic starter fertilizers also contain micronutrients and bacteria that are beneficial to the soil.