A Beginner’s Guide to Fertilizer

Choosing fertilizers may seem daunting but it doesn’t have to be. This post will help you gain more confidence in choosing a fertilizer that is right for you and your plants.

What Is Fertilizer?

Fertilizing is a practice that can be traced back thousands of years. Egyptians, Romans, and Babylonians all have records of fertilizing practices to boost soil fertility and productivity of their farms. They would use minerals and manure to do this and the same holds true till today.

Fertilizers are made to enhance the growth of your plants in several different ways and come down to three macronutrients, Nitrogen (N), Phosphorus (P), and Potassium (K) in this order. These nutrients are vital in the growth of plants. Aside from N-P-K, fertilizers may also contain other important minerals, mirconutirents, and bacteria, to boost soil and plant health.

Why Fertilize?

When you think about plants in an outdoor forest or jungle setting, these plants obtain energy not only from the sun but from the lush forest floor. Falling debris, bacteria, and fungi all do their part in creating enriched soil for those plants to thrive in. In an indoor setting and some outdoor settings, your plants won’t have as much bacteria or organic debris to help enrich it’s soil so you will have to help it along. Depending on the conditions of your soil in your surrounding area, you may also need to fertilize your plants to keep them going.

Depending on the type of plant and the desired effect, you will need to fertilize accordingly. Nitrogen is necessary for leaf growth, Phosphorus is necessary for the development of flowers, fruits, seeds, and roots, and Potassium is necessary for the overall wellness of the plant, such as stem growth and movement of water through the plant. Once this is understood, choosing a fertilizer can become easier. For example, most fertilizers for lawns and grass will have a higher first number, or Nitrogen, to ensure the grass looks greener and produces more leaves.

Types Of Fertilizers

There are so many different types of fertilizers out on the market today. Some are water soluble, some are granular, some come in the form of sticks, and some come as foliar spray. All of the above are fine choices. It really comes down to the levels of each N-P-K, what your specific plant needs are, and what amount of time your lifestyle allows. Some individuals prefer using water soluble fertilizers and some love granular and sticks because they last over a longer period of time. Fertilizers can also be classified as organic or synthetic.

Organic fertilizers are made from a natural source such as seaweed and tend to have smaller numbers in N-P-K. They are not as concentrated as synthetic fertilizers and are considered to be gentler. With lower N-P-K numbers, you won’t have to worry about over fertilizing like you would with synthetic fertilzers. They also take a bit longer to absorb since they tend to enrich the soil that then boosts the plant.

Synthetic fertilizers are synthesized in a lab and tend to have much higher numbers, such as a 17-8-22, and are much more concentrated. They can be absorbed by the plant quickly, but because they are so concentrated, being careful to not over fertilize is important as you may damage or kill your plant from over fertilizing.

Amendments are great to add to your soil along with some fertilizers. Coffee grounds and egg shells are considered amendments and are beneficial to your soil and plant health. Using manure such as chicken, bat, or steer are great ways to organically amend and fertilize your plants and soil since they add in beneficial bacteria and nutrients. These cannot be classified as fertilizers technically, since they cannot guarantee the amount of N-P-K within it.

Breaking Down The Numbers

This may be the most confusing part about fertilizing. What do these numbers mean? On most fertilizers you will see three numbers separated by dashes, such as 2-2-2. Each number represents a macronutrient. Nitrogen (N) is the first number, Phosphorus (P) is the second, and Potassium (K) is the third. These numbers represent the percentage by weight within the package. So a fertilizer of 2-2-2 contains 2 percent of Nitrogen, Phosphorus, and Potassium within the package. A fertilizer of 2-2-2 also means that this is a balanced fertilizer, since no N,P, or K is higher within the product. Aside from the N-P-K, fertilizers may contain filler and or other micronutrients and bacteria that may be beneficial to the soil your plant is in.

To make things easier for myself I remember the numbers this way, first number means green, second number means flowers, and last number is overall health. So depending on what you want or what your plant may need, you can look for product with higher or lower numbers for specific needs. For example, if I want my plant to create more buds or flowers, I may choose a fertilizer that has a higher middle number (P) to help boost my plant in bud production.

How To Use Fertilizer?

Always read the instructions and recommended usage for each fertilizer you purchase! Below is a brief guide and will help give you an idea on how to use it.

  • Water Soluble – Can come packaged as liquid or granular. Add fertilizer to a jug, bucket or watering can in the proper dosage. Mix with water and then thoroughly water your plants with the fertilizer water. Use only once every 2-3 weeks. Cut down dosage if concentrated.
  • Granular Fertilizer – Sprinkle around trunk/stalk of plant without getting too close to the trunk or stalk of plant. Water in thoroughly. Use only once every 3-6 months or as recommended. Cut down dosage if concentrated.
  • Stick Fertilizer – Stick fertilizer into soil making sure it isn’t too close to base of plant. Water in thoroughly. Will slowly dissolve and release fertilizer into soil with every watering.
  • Foliar Fertilizer – Great for plants such as air plants and orchids. Fill a sink or basin with water and soak air plants before spraying with foliar fertilizer. Spray exposed roots and leaves of orchids with foliar fertilizer once every 2-3 weeks.

Plants Use What They Need

It is important to note that just because a fertilizers’ numbers are very high, doesn’t necessarily mean they’re more effective. A plant will only be able to use what they need and any left over macro/micro nutrients and salts in the fertilizers will build up in the soil over time. This can be extremely damaging to the soil your plant is in, killing many beneficial bacteria and fungi your plant needs to thrive.

Heavily concentrated fertilizers also tend to leach out of pots, lawns, and gardens and can accumulate in lakes, rivers, and oceans causing terrible algae bloom. Algae blooms deplete water of its oxygen causing many fish and marine life to perish.

Please be sure to keep this in mind and use fertilizers responsibly. Use your best judgement in the amounts that you are using and in the purpose of using it. Fertilizers are great and at times necessary, but like with most things, too much of anything can be a bad thing.

Key Points To Remember When Purchasing Fertilizer

What are your plants’ needs? Are my plants looking less green, not producing enough fruit, or prone to disease? Each of these ailments have a solution. Plants lacking in green foliage and leaf growth will need a bit more Nitrogen, first number. If you want your plant to produce more fruit, vegetables, or flowers it will require more Phosphorus, or second number. Boosting more root growth also requires more Phosporus. If you have a plant that is prone to disease or is overall just not looking its best, it may need more Potassium, or the last number. If you think your plant would benefit from all the above, a balanced fertilizer would be best.

Do you want an Organic or Synthetic fertilizer? If you have a plant that produces food for consumption I would recommend an organic fertilizer. Organic fertilizes tend to include more beneficial bacteria as well to help boost soil. Synthetic fertilizers are more concentrated and don’t need to be used very often since a little can go a long way. Although this is a plus to synthetic fertilizers, they can be very easily abused. Over fertilizing is very easy to do with concentrated fertilizers. If you are using a synthetic you can cut the recommended dosage in half to prevent over fertilizing.

When and how often should you fertilize? Those who experience a change in seasons should only fertilize within the growing months (Spring to Fall), as this is when your plants will need a boost of macro and micronutrients to sustain growth. Those living in locations that don’t experience much seasonal change can fertilize all year round. Fertilizer should be used sparingly pertaining to type and strength of the fertilizer. For water soluble fertilizers, I recommend only fertilizing once every 2-3 weeks, cut down in dosage if needed. Granular fertilizers can be used every 3-6 months, cut down dosage if needed.

When NOT to Fertilize. It’s important to understand your plant before fertilizing. Fertilizing should be thought of as a vitamin for your plants and not a magic cure all. Do your plants look less than perfect due to its living conditions, such as light and watering schedule? If so, I would suggest improving those areas first before fertilizing. I also recommend not fertilizing during your plants dormant period (Winter). Plants in dormancy aren’t using nutrients for growth since the plant isn’t actively growing during this time.


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