Understanding the Types of Fertilizers
Written by Lee Wyatt (last updated March 23, 2020)
Surprisingly, understanding the types of fertilizers that are available is actually a fairly simple thing. Broadly speaking, there are only two types of fertilizers. The first is called simple (or straight) and the second is called compound or complete fertilizers. While this may be the very broad definition of fertilizers, there are more types that fit within those two definitions that need to be understood. The most common types are listed below, as well as a very simple explanation about each.
- Foliar feeds. Foliar feed fertilizer is a type of fertilizer that you apply directly to the leaves of the plants. This type of fertilizer is the most effective when you are noticing problems where the roots of the plants do not work as they should.
- Phosphate. Phosphate fertilizers are best for younger plants, such as seedlings, that need a lot of phosphate. Most of these kinds of fertilizers are water soluble to some extent, so you will need to reapply them after you water the plants. There are some variants that are slow releasing that don't need to be reapplied as often.
- Potash. These types of fertilizers supply a large amount of potassium to the plants that they are used on. The potassium isn't washed away from the soil very easily, and can be applied well before the plants really need them. In effect, these types of fertilizers are a fairly slow acting one that doesn't get washed away very easily.
- Organic. Organic fertilizers are most often made from some type of...well, organic material. Some examples of this are things like animal manure, soot, compost, and even seaweed. These types of fertilizers are great for improving the overall composition of your soil, and actually contain a variable amount of nutrients that will allow you to customize your mixes easier.
- Nitrogen. Nitrogen based fertilizers are most often used during the spring time when the plants have begun to grow well, and show that they can make use of the nitrogen. There is a major drawback to these types of fertilizers in that they are washed away fairly quickly, and will need to be reapplied often.
- Salt. Surprisingly, if used correctly common table salt can be a hugely beneficial fertilizer. However, if the salt is used incorrectly then you will make the ground unusable for a long time. Do not use more than 1-1/2 ounces to 2 ounces of this agricultural salt per square yard around your root crops. The sodium in the salt will replace the phosphate, and help improve the water and potassium uptake of the plants.