Also referred to as organic fertilizers, natural fertilizers for vegetables have the same key ingredients as inorganic fertilizers--nitrogen, phosphorus and potassium--but they aren't derived from chemical sources. These elements, commonly referred to as the NPK rating, are posted on fertilizer containers and represent the percentage of each nutrient that is in the fertilizer. For example, if the rating reads 1-1-4, then the product is 1 percent nitrogen, 1 percent phosphorus and 4 percent potassium . Most organic vegetable fertilizers are broad spectrum, but there are some specialty products for tomatoes. Organic fertilizers are readily available and easy to apply.
A high-nitrogen fertilizer, bat guano has long been a popular fertilizing option--and not just for those seeking organic alternatives. Bat guano, which comes straight from bats is completely organic and helps to build strong soil as well as fertilize plants. Used by farmers for centuries, bat guano is available in granular form, and may be mixed with existing soil. Though high in nitrogen, bat guano products are available in different NPK ratings, depending on other nutrients that have been added.
Beet-Root Tomato Fertilizer
Though this fertilizer was developed with the idea of producing hearty, healthy tomatoes, it will nurture the rest of your vegetable garden, too. Made from sugar beet roots, beet-root tomato fertilizer has an NPK rating of 1-1-4. This fertilizer, which can be mixed with water and applied with a watering can, works by stimulating microbial activity and providing your plants with important nutrients.
Organic Vegetable Fertilizers
Sold under many different trade names, including Vegetables Alive! (NPK 4-3-1) or Espoma Garen-Tone (NPK 4-6-6), organic vegetable fertilizers are generally broad-spectrum products that are designed to help vegetables root well early and grow strong. These products, which are available at some retailers and online, may be in liquid or granular versions and should be added to your vegetable bed about a month prior to planting and then twice during the planting season.