New Roses, Compost and Grasshoppers

Epazote, Gotu Kola and St. John's Wort

How to help out the Birds

Central Texas Fall Planting Guide

How to order Funeral Flowers

Gardening for Birds and Butterflies

How to grow Apples in Central Texas

How to grow Azaleas

How to grow big Onions

How to grow Pecan Trees

How to grow Salvia

Problems growing Tomatoes in hot weather

Herbs and Late Spring Gardening Tips

How to buy Fresh Flowers

Lawns and Hanging Baskets

Organic vs. Chemical Fertilizers

Organic fertilizers are derived from plant and animal sources. They add ingredients to the soil that make the soil healthy so plants can thrive. As organic fertilizers slowly break down in the soil, they release nitrogen, phosphorus and potassium as well as trace minerals like calcium, magnesium and boron. These elements are taken up by the roots of the plant and become the building blocks which the plant uses for growth and flower production, much like vitamins provide the conditions for a strong cellular structure in humans. Most people don't understand that organic gardening is really about creating healthy soil and not just withholding pesticides. 

Chemical fertilizers, on the other hand,  are best  used to correct a specific deficiency in a plant that shows up in uneven growth or yellowing leaves, for example. An organic fertilizer that works slowly cannot provide things like phosphorous in a way that a plant can consume quickly, so a chemical fertilizer containing only the missing nutrient such as nitrogen, phosphorous or potassium is given to the plant. However, there are  organic fertilizers for specific applications such as blood meal for nitrogen and bone meal for phosphorous that are available. But these organic fertilizers, although they release a certain nutrient, are difficult to apply and regulate when a specific amount is required.  

Each of the elements listed on the fertilizer container, such as 13-13-13, represents the main or most important elements in the fertilizer mixture. These ratios represent the Nitrogen-Phosphorous and Potassium ratio per pound of product. The reason it is lower on organic fertilizers, such as 4-2-3, is because the elements are released slower than with a chemical fertilizer and the organic fertilizer contains other soil building items, such as molasses and manure. However, the elements, no matter where they come from, are the same on a molecular level and are used the same way by the plants. Nitrogen, for example, is a part of the enzymes and amino acids that the plant needs to grow and make new cells. Potassium is an important element because it increases the strength of cellular walls so they cannot burst in extreme temperatures. Phosphorous is important for flower, leaf and fruit production.

Fertilizers are not "plant food" but provide what the plant needs on a molecular level in order for the plant to manufacture food for growth as well as flower and seed production. Fertilizers can affect different plants in different ways. For example, a tomato plant needs nitrogen throughout the fruiting process where a potato plant cannot produce tubers, or potatoes, if too much nitrogen is applied because nitrogen accelerates top green growth at the expense of the tubers.  The best way to find out how much and what fertilizer or nutrients to apply to a lawn or vegetable garden is to get a soil test to find out exactly what you need for best production. There is a list of county extension offices with links at the bottom of this page. Your county extension office can assist you in taking and interpreting a soil sample.

Subscribe to our on-line Newsletter by sending us your E-mail address here.

- Privacy Policy

What are the lastest Landscaping Trends

Tree Recommendations

How to Plant Fruit and Nut Trees

Blossom End Rot

How to grow Bougainvilleas

How to buy Land

Monarch Butterflies

How to grow Camellias

How to care for Holiday Plants

How to care for Mother's Day Gifts

Great Tomato Horn Worm

What are common Shrub Diseases

Container Gardening

Plants for Hot Weather

December Gardening Tips