If You Keep Killing Your Plants, It Might Be Time to Pick Up This Fertilizer

Best Plant Fertilizers

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Do you have a hard time keeping your plants alive? You certainly aren’t alone!

While there could be dozens of variables contributing to your lack of a green thumb (over-watering, under-watering, giving plants too much sunlight, not giving them enough light), keeping your plants well-fed doesn’t have to be one of them.

By incorporating a trusted fertilizer into your day, week or even monthly watering routine, you can help give your house plants and garden the nutrients and minerals they need to thrive. The best plant fertilizers keep every part of a plant healthy, from the roots to the fruits. Great for houseplants, lawns, succulents and basically any and every plant you can think of, fertilizers are a must for anyone with a plant in or around their home.

Let’s explore the wonderful world of fertilizers. In this article, we’ll discuss the components of fertilizer formulas, the types of fertilizer applications and the best fertilizers you can order online.

Understanding Popular Fertilizer Formulas

All fertilizers are made up of some combination of nitrogen (N), phosphorus (P) and potassium (K). One of those elements is always present, and the percentage of each in the fertilizer formula is represented on every bag as a three-part number, N-P-K. For example, a fertilizer for blooms might read 5-50-17 (5% nitrogen, 50% phosphate and 17% potassium) or a fertilizer for the lawn might be 32-0-4 (32% nitrogen, 0% phosphate and 4% potassium). Read on to learn about the key roles of each of these elements in your fertilizer.

Nitrogen (N)

Often nitrogen holds the largest percentage in a fertilizer formula. That’s because it’s thought to be the most important of the three, and plants absorb massive amounts of nitrogen, whether that’s provided through fertilizer or naturally. Nitrogen helps plants grow big and strong as it encourages the production of protein. The protein, in turn, becomes plant tissue, thus providing the essential building blocks of the plant itself. 

Phosphorus (P)

Phosphorus is vital to the process of photosynthesis. The element helps plants produce, store and use energy in order to grow and develop. While nitrogen provides the building blocks to a plant, phosphorus helps the plant to keep growing big and strong throughout its life cycle.

Potassium (K)

Finally, potassium, sometimes called potash, creates disease resistance in plants and also increases crop yields. This means that plants treated with a fertilizer high in potassium will have more blooms or grow more fruit/vegetables. The crops will also be of a higher quality, often resulting in bigger fruits or more luscious blooms. Finally, potassium can also protect a plant during adverse weather conditions by strengthening the root system.

Types of Fertilizer Application

The type of fertilizer you buy will determine how you apply it to your plants. While other application types do exist, the four most popular are:

  • Liquid Soil Application: Many liquid fertilizers can be sprayed on the soil surrounding a plant once diluted. These fertilizers work to break down dirt, extracting extra nutrients to feed the treated plants.
  • Foliar Application: Some liquid fertilizers are meant to be sprayed on the leaves of your plants. These fertilizers provide nutrients directly into the plant through the pores on the foliage. This allows for quicker absorption rates and fast results.
  • Pellets: Quite a few fertilizers come as a solid in the form of pellets. These are usually spread around plants and can have a continuous release formula for treatment over a long period of time.
  • Spikes: Probably the least popular type of fertilizer application, spikes are useful for indoor plants as well as trees and shrubs. These spikes are driven into the ground surrounding plants. They then release nutrients into the soil over a lengthy period of time. Some fertilizer spikes can treat plants for up to six months.

Now that you know a bit more about how the best fertilizers work, check out some of our favorite products. These top-rated fertilizers will help your plants grow and thrive.


1. Miracle-Gro Water Soluble All Purpose Plant Food


The go-to fertilizer for years, Miracle-Gro’s all-purpose plant food is easily the best and most popular fertilizer on the market. Made to help cover up to 600 square feet, this powerful fertilizer is meant to be attached directly to your hose and sprayed anywhere and everywhere you think your plants need extra nutrients. You can also add a tablespoon to your watering can to help feed your flowers. For best results, Miracle-Gro suggests using this fertilizer every 7 to 14 days.

best fertilizer miracle gro water soluble Image courtesy of Amazon


2. Miracle-Gro Continuous Release Plant Food


Everyone dreams of having their very own vegetable garden, but sometimes getting your garden up and running is easier said than done. This Miracle-Gro plant food formula is designed for everyday fruits and vegetables and contains natural ingredients to help enrich your soil and give your veggies and fruits the nutrients they need to grow. Each spray is built to last up to three months.

best fertilizer miracle gro continuous release Image courtesy of Amazon


3. Miracle-Gro Succulent Plant Food


Succulents are a tricky bunch. Sure, they’re designed to be more resistant than other houseplants, but the slightest change in environment can have a dramatic impact on their health. Fortunately, Miracle-Gro is a helpful spray fertilizer that can help promote growth and keep your succulents looking well cared for. Simply apply to the soil or mix it with your plant’s water once every two weeks.

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4. Miracle-Gro Tree & Shrub Plant Food Spikes


Although you might not think about fertilizing the trees and shrubs in your yard, your bigger plants need love, too. The Miracle-Gro Tree & Shrub Plant Food Spikes are an easy way to feed these plants in the spring and the fall. Simply drive the stakes into the ground to provide extra nutrients to above and below the surface. In turn, your trees and shrubs will display vibrant color and dense foliage throughout the year.

best fertilizer miracle gro tree shrub Image courtesy of Amazon


5. Proven Winners Continuous Release Plant Fertilizer


Fortified with 15% nitrogen for foliage growth, 7% phosphate for flower product and 15% potassium for disease resistance, the Proven Winners Continuous Release Fertilizer is a great low-cost option for your flowering plants. Designed to feed your plants up to six blooms, the smart-release pellets are meant to be sprinkled over your plants for months-long nourishment. Great for both potted and natural plants, this is an easy way to help add some nutrients without breaking the bank. Don’t forget to keep watering.

best fertilizer proven winners Image courtesy of Amazon

6. Houseplant Resource Center Indoor Plant Food


Have a few fussy houseplants that need a little extra TLC? This all-purpose liquid plant fertilizer includes nitrogen and phosphorus that are essential to plant health. Simply add one teaspoon for every two cups of water for a little extra love. Made with natural ingredients, this fertilizer is best used with indoor plants and should (hopefully) help remove brown spots and put an end to those brittle yellow leaves.

best fertilizer houseplant resource center Image courtesy of Amazon

7. JR Peters Jack’s Classic Tomato Feed


There’s nothing better than eating a fresh tomato directly from the vine at the end of a sunny, hot summer. Make sure you have plenty of opportunities to do so by feeding your tomato plants with JR Peters Jack’s Classic Tomato Feed. The optimal combination of nutrients, including a healthy dose of potassium, will help your vine plants produce a good crop. In addition, this fertilizer will also help your plants to create strong vines and vibrant, green leaves. Just keep in mind that this is not an organic fertilizer, so it will not produce organic tomatoes.

best fertilizer jr peters jacks tomato Image courtesy of Amazon

8. Simple Lawn Solutions Natural Liquid Fertilizer


A smart blend of crucial ingredients for your lawn, this fertilizer features no harmful chemicals and includes nitrogen, phosphorus and potassium nutrients to keep your grass healthy and green. It’s great for Bermuda, St. Augustine, Zoysia, Buffalo, Centipede, Florida Palmetto, Bahia, Fescue, Ryegrass & Kentucky Bluegrass. This 32-ounce spray is sure to help support your grass’s growth.

best fertilizer simple lawn solutions Image courtesy of Amazon

9. Osmocote Plus Smart-Release Plant Food


Made for both indoor and outdoor plants, this Osmocote fertilizer features a smart-release filtration system that’s designed to control the release of nutrients—meaning it continues to work over time. Packed with 11 vital nutrients for all types of plants, one pack is designed to feed your plants up to six months. Best of all, it works with virtually any type of plant, regardless of whether it’s potted or not.

best fertilizer osmocote plus smart Image courtesy of Amazon

10. Grow More Hawaiian Bud and Bloom


Everyone who has flowering plants, whether they are tropical or not, knows that a healthier plant creates more blooms. So, to maximize your bloom count, you must fertilize your plants, and a fertilizer that’s high in potassium is most recommended. That’s because potassium is the part of a fertilizer that creates a high yield (or bountiful crop). Luckily, the Grow More Hawaiian Bud and Bloom Fertilizer has 17% potassium in its formula along with 50% phosphate for healthy roots and 5% nitrogen for better foliage. It’s also urea-free and recommended for use on all orchids, bromeliads, guzmanias, tropical succulents and xerophytes.

best fertilizer grow more hawaiian bud Image courtesy of Amazon

11. GS Plant Foods Organic Kelp Fertilizer Concentrate


When you think of fertilizer, seaweed, or kelp, may not be the first thing that springs to mind. However, just as the natural product of the sea has become a superfood, it can be considered a superfood for plants, too. Using kelp on plants massively improves their root systems, because kelp contains large levels of cytokinin which promotes cell division. This, in turn, encourages new root production and improves photosynthesis. If you’re ready to try kelp on your plants, grab a bottle of GS Plant Foods Organic Liquid Kelp Fertilizer Concentrate. Dilute the liquid in water and spray it on your plants’ leaves every one to two weeks.

best fertilizer gs plant foods organic Image courtesy of Amazon

12. Dr. Earth Premium Gold All Purpose Fertilizer


This Non-GMO verified fertilizer comes in a variety of different sizes and is safe for people, pets and, of course, plants. Enriched with minerals, nutrients and more, this fertilizer includes no synthetic chemicals and is consistently tested for the highest levels of purity and transparency. Great for both indoor and outdoor plants, Dr. Earth works with veggies, potted plants, shrubs, annuals, perennials and more.

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13. Jobe’s Organics Purpose Granular Plant Fertilizer


If you want one fertilizer to work for all your plants, you’ll need to choose an all-purpose formula. Remember back to when we discussed the nitrogen, phosphate and potassium percentages in fertilizers. Where a fertilizer for a specific purpose will have more of one than the other two, an all-purpose fertilizer tends to have the same amount of all three. For example, this Jobe’s Organics Purpose Granular Fertilizer has an N-P-K rating of 4-4-4. The pellets, which contain a powerful biozome, can be mixed with your soil at various stages in your plants’ lives to break down the dirt into plant nutrients. In this way, it gives plants of any type more food for growing big and strong.

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14. Fox Farm Liquid Nutrient Trio Soil Formula


Different fertilizers work best at different points in the growing cycle, so Fox Farm developed a three-pack of its best soil formula fertilizers for all stages in a plant’s life. First, Grow Big can be used from planting for abundant shoot and foliage growth. Once you see the first sign of bud set or flowering, switch to Tiger Bloom, which is an ultra-potent, high-phosphorus fertilizer. Finally, use Big Bloom once flowers or fruits develop in order to provide the nutrients the plants’ root systems need to continue to survive. Together, these three fertilizers pack a powerful punch.

best fertilizer fox farm liquid nutrient Image courtesy of Amazon


15. Scotts Turf Builder Lawn Fertilizer


One of the top reasons people buy fertilizers is to build luscious, green lawns. Grass benefits greatly from fertilizers like Scotts Turf Builder Lawn Food. When used every six to eight weeks, this fertilizer helps grass build deep, strong roots that help protect the grass shoots from heat and drought. Plus, Scotts has developed the My Lawn App, which tells you exactly how much fertilizer you need to buy based on the square footage of your yard. Furthermore, this fertilizer can be applied to any grass type in any season, making it one of the most versatile lawn foods on the market.

best fertilizer scotts turf builder Image courtesy of Amazon