These fertilizers are also useful to supplement granular fertilizers for potted plants because frequent watering of containers leaches nutrients. They are great as a starter solution and for a quick boost during the growing season. The advantage of liquid fertilizers is that they are quickly absorbed, so plants get their benefits soon after you apply them. The liquid nutrients generally last 1 to 2 weeks, so you need to reapply often. They usually require a hose-end sprayer or watering can. Liquid fertilizers, such as Miracle-Gro® Water Soluble Tomato Plant Food and Miracle-Gro® LiquaFeed® Tomato, Fruits & Vegetables Plant Food, are water-soluble powders or liquid concentrates that mix with water to make a fertilizer solution. Typically, a gardener might overload the soil in spring, when it is cold, but won't know it until summer warms things up and the tomatoes are all leaf with no fruit! Liquid Therefore, you have to be careful about applying too much organic fertilizer, because if microbial activity releases more nutrients than the plants take up and the soil can hold, the excess can wash away.

Microbes aren't very active when the soil is colder than 50 degrees, and according the USDA, a rule of thumb is that for every 18-degree increase in soil temperature, the microbial activity doubles. Organic fertilizers tend to encourage soil microbes, earthworms, and other flora more than synthetic fertilizers do, because most organic fertilizers don't add excess salts and acid to the soil. Organic fertilizers depend on the microbes in the soil to break them down into digestible bits for plants. These are considered okay for organic gardening because they are not synthesized, but come from natural mineral-rich deposits in the earth. There are also some natural fertilizers that are not organic, such as Greensand, which contains potassium, iron, calcium, and other nutrients. Organic fertilizer comes from an organic source such as manure, blood meal, cottonseed meal, feather meal, crab meal, or others, as opposed to synthetic sources. Miracle-Gro® Shake 'n Feed® Tomato, Fruit & Vegetable Plant Food is a continous-release granular fertilizer developed especially for edibles. When applied at the right rate and in places where they don't wash away, these high-tech products are more environmentally sound because they are less likely to contribute excess nutrients to any runoff that ends up in local streams. Little is wasted and they last longer, so even though their price is higher, they are actually more economical than uncoated, farm-grade types. The nice thing about coated granular fertilizers is that you apply them only once or twice during the growing season and they gradually release nutrients in tiny doses as roots can take them up. They depend on moisture and temperature for release. They are coated to control the rate of release typically from 2 to 9 months, depending on the formula, whereas uncoated (and cheaper) farm grades last only 2 to 4 weeks. Miracle-Gro® Shake ‘n Feed® Tomato, Fruit & Vegetable Plant Food, have 'slow-release,' 'timed-release,' or 'controlled-release' properties, synonymous terms meaning that they release their nutrients slowly over a period of time. You may be familiar with common granular farm-grade fertilizers such as 8-8-8 and 10-10-10. It's often good to work them into the ground before planting. Because they must first break down before releasing nutrients, it usually takes a watering and a few days to begin to see their results. They last 1 to 9 months, depending on the type.

These are meant to be worked into the soil or sprinkled around plants. Plants quickly take up most water-soluble fertilizers, while granular fertilizers need a while to dissolve or decompose before plants can access their nutrients. Granular fertilizers are solid granules, while liquid fertilizers are made from water soluble powders or liquid concentrates that mix with water to form a liquid fertilizer solution. What is the difference between granular and liquid fertilizer? Then read below for more about the different forms of fertilizer. What are the differences among the many forms of fertilizer that you see on shopping aisles? What is a granular fertilizer? What about water-soluble? What are slow-release, timed-release, and controlled-release? What is an organic fertilizer? If you have questions about the numbers on the bag, read What's in a Package of Fertilizer? first.

Solid and liquid fertilizers