An Array of Organic Fertilizer Options for Your Plants (2024)

Updated October 13, 2022

Jobe’s Organics All-Purpose Granular Plant Food tops our list of organic fertilizers because it’s recommended for use on vegetables, flowers, shrubs, and trees. It can even be used for seed starting. It’s ideal if you only want to keep just one type of fertilizer on hand.

This balanced NPK ratio of 4-4-4 can be worked into the soil at planting or applied to existing plants at the drip line. It includes beneficial bacteria, fungi, and other microorganisms to boost the long-term health of your soil. However, smell can linger indoors, so it may be best for outdoor and well-ventilated spaces. It's backed by a manufacturer guarantee.

If you’re planting seeds or moving transplants into the garden or containers, consider using a starter fertilizer. With a NPK of 2-4-2, the slightly higher ratio of phosphorus contributes to root establishment.

Dr. Earth, which has been creating organic products since its founding in 1991, composts food grade waste instead of letting it end up in landfills. The company is also a sponsor of the Sustainable Food Trade Association, which promotes socially responsible business practices for the organic food trade.

Worm castings are the digested “soil” produced by worm farming or vermicomposting. They provide some macronutrients for leaf growth; in this case, its NPK ratio is 1-0-0. But they also contain micronutrients and beneficial microbes, and improve drainage and soil structure.

Best of all, if you’re sensitive to odors (or have pets who like to nibble!), earthworm castings don’t have a strong aroma like other organic fertilizers. They smell like rich, black garden soil. You can use these castings by adding them to the bottom and sides of the holes you dig for planting seeds or transplants, and as side dressing throughout the season.

This fertilizer has a NPK ratio of 2-3-1, so it’s a good all-purpose product that many gardeners prefer for its ease of use (you mix it up in a watering can). The company, which started as a wholesale fish distributor in 1965, worked with the state of Massachusetts and local universities to devise a way to utilize fish by-products from the fillet process, rather than allowing the remains to be dumped back into the ocean.

As you probably guessed, the product smells strongly of fish, but it dissipates within a day—faster than many other organic products. There’s also nothing for pets to dig up and eat, though they still may nose around the application area.

With a NPK ratio of 5-7-10, this product is specifically designed to promote heavy blooms and overall plant health. The bottle is made from 25% recycled plastic, and the company launched the Parks for Pollinators program in 2017 to expand pollinator habitats in parks across the country.

Work the granules into the soil when planting, or shake on to existing plants. The shaker canister delivers an even amount over the soil surface.

Heavy feeders such as tomatoes use nitrogen quickly, and this product is formulated to supply plenty, with NPK at a 5-7-3 ratio, as well as calcium to fend off blossom end rot. Blossom end rot is a nutrient deficiency which causes your tomatoes look perfect on top, but then turn ugly black on the bottom.

Beneficial fungi also is included to help build healthy soil. Use the granules in containers or in-ground plantings.

Overfeeding houseplants can cause them to develop spindly growth or become more vulnerable to pests and diseases. These pre-measured spikes, with a balanced 4-4-4 formula, make it easy to fertilize properly without having to mix anything.

Stick one in the soil of your houseplant's pot (or several for larger pots) for no-mess feeding. The odor is almost non-existent, which makes them a better choice for indoor fertilizing. You’ll use them every eight weeks during the active growing season, which is spring to fall for most houseplants.

Although succulent plants typically don’t need to be coddled, which is why so many people love them, they can benefit from feeding during their active growth period in the spring or summer. This applicator bottle doses out just what you need to use when watering.

While the 1-2-2 NPK formula is on the stinky side, the odor doesn’t linger long. The company’s products are approved for organic use by the California Department of Food and Agriculture (CDFA), and its factory is 100% solar powered with an emphasis on zero waste manufacturing.

Here at Treehugger, we're big fans of lawn alternatives, but if you do have grass to feed, this organic fertilizer will do the trick. With a balanced 7-0-7 ratio of NPK, this granular food is designed for summer fertilization and is pelletized for easy application. It’s safe for pets and kids to walk on immediately after applying, and it greens up lawn without burning grass.

Registered with OMRI, the ingredients include soy meal, potash, and humic acid for healthy soil. It does not contain any animal by-products or waste products.

Final Verdict

Treehugger Tips

There are also many things in your kitchen that can serve double-duty as plant fertilizer, from eggshells to banana peels. But before you start dumping coffee grounds onto the closest plant, but you’ll need to learn about the kinds of nutrients the plant species in your garden need and what different kitchen cast-offs offer. Check out our guide to making homemade plant food.

Frequently Asked Questions

• Do you have to buy organic fertilizer?

  Not necessarily.Composting is a great way to make your own fertilizer. It does take some time and effort, but composting offers huge environmental benefits in terms of building soil, reducing landfill, and even preventing planet-heating greenhouse gas pollution. It can even be done for free.

  Learn More: How to Compost at Home
  

• What is the best natural fertilizer for vegetable gardens?

  Our choice for vegetables and tomatoes is Happy Frog Tomato & Vegetable Fertilizer. However, you can also use a good all-purpose fertilizer for most vegetables, like Jobe’s Organics All Purpose (Treehugger’s top overall pick).

  If you also compost, working some mature compost into your soil is also a great natural way to fertilize a vegetable garden.

• Can I make my own liquid organic fertilizer?

  Yes! Liquid fertilizers can help plants get nutrients quickly. If you already compost, then making compost tea is one of the easiest liquid fertilizers to make yourself. Simply add compost to water and let it sit for a couple of weeks. Then strain out any particles (they can go back in the compost pile) and apply the liquid to plants. This mix is best used on mature plants, and is not ideal for tender seedlings.

  Learn More: How to Make Organic Liquid Fertilizers

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