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Best Fertilizer

The best organic fertilizers for general gardening are a combination of fish ingredients such as fish emulsion or fish meal. Fish emulsion alone provides a solid Nitrogen, Phosphorus, and Potassium (NPK) nutrient factor which makes a terrific fertilizer base. The best fish emulsion fertilizers aren’t cooked but rendered in a cold making process that keeps the vitamins essential to plant growth fully intact. Can certain other organic products be substituted or added to enhance or replicate this formula? Of course, but starting out with a fish emulsion base assures you that your plants will have the essentials for superior growth and health.

The organic fertilizers on this list were selected because they contain the necessary ingredients that every organic fertilizer should have to make your plants lush and bountiful, they’re proven to work based on manufacturers testing, and provide a fertilizing component that will work equally well for both the novice as well as the experienced gardener.

Neptune's Harvest Organic Fish and Seaweed Fertilizer

For the best in a fish emulsion/seaweed organic, nothing beats Neptune's Harvest Organic Fish/Seaweed Fertilizer Blend 2:3:1. This liquid fertilizer is easy to use; just mix 1 tablespoon of fertilizer into a gallon of water for house plants, or mix 1 ounce per gallon for your outdoor garden plants. The cold process fish emulsion used in this mixture means that all essential vitamins and nutrients are retained to be absorbed by your plants for superior growth. Pour this mixture at the base of plants and do this every 3 weeks for maximum growth and blooming. Put a mixture into a spray bottle to feed your plants, and spray the leaves until they are saturated on both the top and the bottom sides.

Although a more expensive process to retain the nutrients, there is no fish emulsion-based organic fertilizer on the market that works better for your plants. This is an Organic Materials Review Institute (OMRI) listed product, meaning it’s been tested and certified by the foremost non-profit and independent organic testing facility. They have been recognized as a leader in organic testing by the USDA National Organic Program.

Milorganite 0636 Organic Nitrogen Fertilizer

For the greenest organic lawn you'll ever have, use Milorganite 0636 Organic Nitrogen Fertilizer. This nitrogen heavy fertilizer, with an NPK rating of 5:2:.3, will make any plant green, lush, and works best for use on lawns. Milorganite meets the EPA's exceptional quality standard, and it is certified by the USDA as a bio-based product. This is the fertilizer that the best national golf courses use, and you'll get the same lush and thick green results that they do.

As far as application goes, aim for four times per year on Memorial Day, July 4th, Labor Day, and Thanksgiving. Apply 36 pounds per 2500 square feet, and your lawn will be growing green and lush all season long. You can even apply Milorganite during dry weather without having to worry about it burning, plus it acts as a natural deer repellant around bushes, trees and gardens that you want to protect.

OMRI Organic Trace Mineral Soil Additive Fertilizer

For the best booster for your fertilizer, get Azomite - OMRI Organic Trace Mineral Soil Additive Fertilizer. It’s contains 67 minerals and trace elements including calcium oxide, manganese oxide, bismuth, copper and a wealth of other nutrients and minerals. It's NPK formula is low, with .15:.15:5, so it’s best used as an additive, although if you apply it often enough it work as a stand-alone fertilizer..

You can use between 40 grams to 120 grams per plant, so just mix in the appropriate amount to your regular organic fertilizer, and you'll be good to go. Give an extra boost to your plants by adding OMRI certified Azomite for the best organically grown garden that you've ever tended.

Espoma PT4 4-Pound Plant-Tone Organic 5-3-3 Plant Food

Since 1929, no one makes a better granular organic fertilizer than Espoma Plant-Tone Organic 5-3-3 Plant Food. At a 5:3:3 NPK formula, it has just about the perfect formulation every plant needs for healthy leaves and heavy fruit production. It can be used in gardens, on lawns, potted plants and on virtually anything else that grows.

Mix it into the soil about 4 inches deep, once per month, at 4 pounds per 100 feet of dirt. Lawns take 20 pounds per 1000 feet, 3 times per year, trees are fed twice per year and indoor potted plants get 1 teaspoon mixed in with the soil, once per month. This easy to use formula combines balanced feeding of 15 essential nutrients with tested and proven results. This is one of the easiest organic fertilizers to use, and the results will be worth it every time.

Jobe's 6528 Organic All Purpose Fertilizer Food Spikes

If you want the easiest organic fertilizer with no muss or fuss, use Jobe's 6528 Organic All Purpose Fertilizer Food Spikes. They are so easy that you simply push them in next to your plants and forget them. Really, that's all there is to it.

These fertilizer spikes get the plant food down where the roots are, making them one of the most efficient methods there is for feeding. Rain water or regular watering releases the nutrients, and your plants are automatically fertilized. Press them in next to a plant, once per year, and that's all there is to it.

They have a balanced NPK of 4:4:4 and they are OMNI certified organic. Sure, many people may scoff at the Jobe's name, but the truth is these are quality organic fertilizer spikes, and if you don't have the time needed to spend on your garden or other plants, this is the fertilizer for you.

Dynamite Magic Plant Food

If you want the best tomato fertilizer with the lowest price on the list, Dynamite Natural and Organic Mater Magic Plant Food is for you. The 8-5-5 NPK rating means not only will you get lush plant growth, but that you'll also get tomato plants which produce big, healthy fruit.This complete tomato plant food comes with essential nutrients such a manganese, zinc, copper and others, in a concentrated formula. You can apply this fertilizer at 1 tablespoon per square foot every 3 months. Once applied, mix it into the soil and water as usual. It’s OMRI certified organic, and although made specifically for tomato plants, it can be used as an organic fertilizer for all of your plants.

Espoma TO8 Tomato-tone 3-4-6

The Espoma Company has been in business for almost 90 years, and they pride themselves on their fertilizers. This is a 3-4-6 fertilizer and those NPK numbers make it the best balanced fertilizer here. The ingredients include poultry manure, bone meal, alfalfa and cocoa meal, as well as potash, calcium and sulfur, being among some of the 15 essential nutrients.

The fertilizers formulation will make it very difficult to burn or over-fertilize your tomatoes, yet provide you with the best growing results possible. You may need to use this fertilize more often, but you’ll get superior results in return. 3 tablespoons of fertilizer per plant gets mixed into the soil, then water as you would normally; do this twice per month during the growing season.

Dr. Earth 704P Organic 5 Tomato, Vegetable & Herb Fertilizer

Dr. Earth 704P Organic 5 Tomato, Vegetable & Herb Fertilizer contains soil microbes that help break down organic material and speed the process of changing fertilizer to food. This 5-7-3 fertilizer also contains ground fish meal and seaweed as its main basic ingredients so your tomato plants will take in more nutrients every single growing day, and they will grow faster and taste better.

Although it’s made to target and feed tomato plants, it’s good enough to use as a whole garden fertilizer. 1 1/2 cups are spread over a 10 square foot area, mixed in with the soil and watered as usual. The NPK ratio makes plants hardier and tougher which would be an ideal fertilizer for more northern climes.

Schultz Tomato Food Fast Acting Water Soluble

If you don't want to grow organic yet desire the best tomato plants you've ever seen, Schultz Tomato Food Fast Acting Water Soluble 17-18-28 is exactly what you need. With this super concentrated fertilizer, you'll sprinkle 1/2 cup around the base of each large tomato plant and water as usual, then feed every 6 weeks during the growing season. In addition to the outstanding NPK rating, this fertilizer also contains essential nutrients such as copper and manganese. This is powerful stuff, so remember to wear gloves during fertilizing with this product and always brush or water wash your plants leaves after application to prevent burning.

Miracle-Gro LiquaFeed Plant Food

If you want the absolutely easiest to feed tomato fertilizer in a non-organic formula, than Miracle-Gro 100440 LiquaFeed Tomato, Fruits and Vegetables Plant Food is the way to go. This is a 9-4-9 NPK ratio fertilizer, so you'll get lush growth with heavy fruit production. It’s fortified with essentials for overall plant health, but who knows where all of the ingredients come from or what they are made of.

Although you can actually measure out 2 teaspoons per gallon bucket of water and use it in a watering can, the best way is to get the special hose handle and sprayer that goes along with this. You literally just pop this bottle into the sprayer handle, then water your garden normally as the fertilizer automatically gets distributed. One bottle covers 400 square feet of garden and it should be used every 7 to 10 days.

Milorganite 0636 Organic Nitrogen Fertilizer

For the greenest organic lawn you'll ever have, use Milorganite 0636 Organic Nitrogen Fertilizer. This nitrogen heavy fertilizer, with an NPK rating of 5:2:.3, will make any plant green, lush, and works best for use on lawns. Milorganite meets the EPA's exceptional quality standard, and it is certified by the USDA as a bio-based product. This is the fertilizer that the best national golf courses use, and you'll get the same lush and thick green results that they do.

As far as application goes, aim for four times per year on Memorial Day, July 4th, Labor Day, and Thanksgiving. Apply 36 pounds per 2500 square feet, and your lawn will be growing green and lush all season long. You can even apply Milorganite during dry weather without having to worry about it burning, plus it acts as a natural deer repellant around bushes, trees and gardens that you want to protect.

Safer Brand 9333 Ringer Lawn Fertilizer

Here’s a fertilizer you may not be familiar with, but it offers you the most bang for the buck on this list. Safer Brand 9333 Ringer Lawn Fertilizer gets it's nitrogen from feather meal and uses bone meal to slowly release it along with soybean as a filler to keep the concentrations even. This slow release formula promotes such thick grass growth your lawn will naturally choke out weeds.

This high nitrogen formula has an NPK ratio of 10-0-6, so it’s made to give you a very green, lush lawn. 25 pounds covers 5000 square feet, and is safe for use around kids and pets. This all plant-based organic formulation works on all types of grass so if you have a lawn that doesn't respond to any other fertilizer, this is the one for you.

Miracle-Gro 1001832 Lawn Food

If you want bragging rights in your neighborhood for the most lush, greenest lawn, then you want Miracle-Gro Water Soluble Lawn Food. The extremely high 36 percent nitrogen content along with 6 percent potassium content will make sure that your lawn is world class in every respect.

This fertilizer is basically steroids for your lawn, feeding it both through the leaves as well as through the roots. Mixing must be precise or you may end up burning your lawn. Kids and pets must also be kept off the grass for 24 hours after use. But you may only need to feed once or twice per year for outstanding results, and one 5 pound box covers 4000 square feet.

Keep in mind this is not an organic fertilizer. Although it’s easy to use and inexpensive, you'll have to schedule a household hazardous waste pick up as it cannot be disposed of in the trash if you end up not using it all.

Scotts Turf Builder All Season Lawn Fertilizer

Perhaps the best known lawn fertilizer in the world is Scotts Turf Builder Lawn Food, and the reason is grass simply thrives on this formula. Scotts has a 32 percent nitrogen content coupled with a 4 percent potassium content and 12 pounds feeds 5000 square feet. Recommended feeding time is between 6-8 weeks during the growing season.

This is one of the least expensive fertilizers on this list, it holds water in the soil to keep your grass hydrated longer and it is available almost anywhere. Although kid and pet friendly, it’s not classified as an organic or natural fertilizer and you'll need to call your local solid waste disposal agency if you discard any unwanted portions.

Espoma Organic Based Lawn Food 15-0-5

From one of the most respected garden fertilizer companies around comes Espoma Organic Based Lawn Food 15-0-5. Espoma has been in business for almost 90 years, so their reputation for quality plant products is second to none Although this is one of the more expensive lawn fertilizers available, it gives a growing performance that rivals any of the other top rated products.

The organic formula features a 15 percent nitrogen content for rapid feeding and slow release greening, with a 5 percent potassium content. This lawn food is safe for kids and pets, and can be applied all season long, feeding at 3.3 pounds per 1000 square feet, and it is fed 4 times per year during the growing season. Simply apply to a dry lawn and water lightly after application.

Buyer's Guide


Fertilizer Buyers Guide

Fertilizer has been used for virtually as long as humans have been growing food crops. In the “new world”, Native Americans taught the colonists how to use fish heads as fertilizer to supplement their corn and other food crops. The fish heads were dried out and then ground up to effectively create the first powdered fertilizer; in this form it could be used anywhere and stored easily. In fact, a derivative called fish meal remains one of the main ingredients found in many fertilizers to this day.

In this modern world, a wealth of manufactured and organic fertilizers are available to choose from. However, different types of plants need different types of nutrients for optimum growth and productivity. This guide only provides the most basic of information so for a more in-depth understanding of fertilizer, contact a certified horticulturist, a home and garden specialist, or an agriculture expert at your local university.

Fertilizer Ingredients

Virtually every fertilizer is classified by the three basic ingredients needed for healthy plant growth. These are nitrogen, potassium and phosphorus, or known as N-P-K numbers.

“N” is for nitrogen.
Nitrogen is one of the basic building blocks in every plant. It affects the health and growing cycle of a plant cells and is naturally derived from organic decomposition. The more nitrogen added to the soil, the taller and more vigorous a plant will grow. Since nitrogen allows a plant to produce more chlorophyll, plants with an abundance of nitrogen will also be a darker green than those that don’t grow in nitrogen rich soil.

“P” is for Phosphorus.
Phosphorus promotes root growth and blooming. This naturally occurring substance comes from both the weathering of rocks and minerals into the ground. The uptake of these minerals occurs from organisms which eat decaying plant matter and then excrete the phosphorus back into the soil.

“K” is for Potassium
Potassium is like a medicine plants need to remain healthy. This compound makes a plant more drought resistant, improves root development, and it makes a plants photosynthesis, (the process that uses sunlight to synthesize food from carbon dioxide and water) more efficient.

Other Ingredients
Although the N-P-K numbers are only used to show the nitrogen, phosphorus, and potassium content, there are generally other nutrients added. These “micro-nutrients” are comprised of such ingredients as iron, manganese, molybdenum, zinc, and copper, among others. Much like people who take a multi-vitamin to ensure they get all of their nutritional needs, adding in these micro-nutrients (plus trace elements like sulfur, calcium, and magnesium) gives plants their own full multi-vitamin nutritional needs.

Fertilizer Types

Manufactured fertilizer is generally inexpensive and will promote stellar plant growth with an abundance of flowers and fruit. It’s usually high in nitrogen and phosphorous which contributes to rapid green plant growth while also promoting flowering and larger fruit yields.

Ammonia and nitric acid are combined to achieve high nitrogen levels in the form of ammonium nitrate. Phosphorus is manufactured by dissolving mineral laden rocks in sulfuric acid, while potassium is made by treating potassium hydroxide with hydrochloric acid. Micro-nutrients and trace elements can then be added to this mix for a more complete fertilizer, such as ground up animal bones for calcium and powdered molybdenum and zinc metals, among others.

Organic fertilizers are made from all natural ingredients with the largest source of organic fertilizers coming from manure, compost, blood meal, and seaweed. For example, manure and blood meal produce both nitrogen and phosphorus while seaweed, compost, and wood ash are great sources of potassium. While micro nutrients and trace elements can be added to these fertilizers, most of the essentials are already present since the plant and animal compounds already contain them naturally.

Synthetic vs. Organic

There’s an ongoing debate about which type of fertilizer is healthier to use for you and your plants. The most comprehensive study to date from the Newcastle University in London, England, has proven that organic foods are healthier and provide more base nutrients and anti-oxidants than commercially grown food.

In general, manufactured fertilizers can be engineered to last longer and require less fertilizing than their organic counterparts. Very high N-P-K numbers can be achieved with manufactured fertilizers, because you can concentrate the ingredients through artificial means. By adding a coating to the fertilizer granules, these types can be made to dissolve slowly over the course of weeks or months. You may only have to feed your plants 2 or 3 times throughout the year to maintain healthy and productive growth.

On the other hand, organic fertilizers break down quickly once spread. They have lower N-P-K numbers and because of this you'll need to fertilize more often, sometimes weekly if your plants are heavy feeders. They are more time consuming to use and require more work to use utilize correctly. However, if you're concerned about chemicals showing up in your edible plants, organic fertilizers are the way to go.

What's Best for You

Lawns, Trees, Shrubs, and Houseplants
These plants are all ornamental for which any good high nitrogen fertilizer will work. Remember, the nitrogen makes plants green and ornamental plants such as lawns and shrubs look the best when they have a vibrant, dark green hue. A high nitrogen content is the most valued fertilizer for these types of plants, but in southern climes or where the weather can be dry over long periods of time, a fertilizer which contains a higher potassium count will help promote deeper root growth.

Flowering Plants and Trees
The most valuable fertilizer for these plants are those with a higher phosphorus content. Certainly, both nitrogen and phosphorus are needed, but a flower garden or ornamental flowering trees will produce a greater amount of larger, longer-lasting flowers if the fertilizer has a higher phosphorus content.

Edible Plants
Fertilizers with a lower nitrogen content with higher phosphorus and potassium contents are the best fertilizers for edible plant gardens. Plants bearing edible fruits and vegetables need to produce more flowers and buds, and this also goes for fruit trees as well. They also need to be hardy and disease free, so both the phosphorus and potassium ingredients should be more prominent for edible plant gardens. In doing so, you'll reap the rewards in the form of more fruit on healthier plants.

Dale Y
Dale Y has been writing about home improvement and Do-It-Yourself projects for more than a decade, using his own hands-on maintenance, construction and facilities management experience as a guide. He has covered the gamut by writing about news and views, home and garden ideas, home and business maintenance, and property management. As an offshoot, he had his own sewing machine and small appliance repair business, and can tell an embroidery stitch from a stretch stitch, all the while cooking the best salmon fillet ever on a countertop grill, while making a smoothie in the latest bullet blender. In this capacity, he has used a wide variety of tools and equipment for every need, worked with products ranging from adhesives to solvents, sewed shirt sleeves with a #14 needle and finished leather appliqué with a #18 needle.
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