Best Fertilizers for Your Garden

A good fertilizer can be the difference between stunning, sellable flowers and sad, floppy stems. It can be the difference between a bountiful harvest of corn and, frankly, no harvest at all (trust me, I know from experience!).

I’ve used several different fertilizers over the years and have finally figured out the perfect mix of soil enhancers and compost teas for my vegetable garden and flower farm. In this short blog post, I’ll share my six favourite fertilizers for regular-season gardening and why they make the list!

A collection of gardening products and flowers displayed on a white table outdoors. Products include liquid fertilizers and plant enhancers. Surrounding the products are various flowers, including sunflowers and zinnias, with a green, leafy backdrop in sunlight.

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The Best Fertilizers for Your Garden

E.P.S.I.

E.P.S.I. (essential probiotic soil inoculant) is a fertilizer from Lily Plain Gardens that I started using in 2023. It’s made right here in Saskatoon and is a shelf-stable, chemical-free compost tea that fertilizes and fixes your soil. It comes highly recommended to me by Dave Kearnsy of Kearnsy Consulting. If Dave is passionate about something, I usually go get it and use it without question.

When first using it, I noticed a difference applying it to my plants that look like they need some help. The plants in the first half of my high tunnel were doing well, and the back half was struggling. We’ve since used the E.P.S.I. to continue to help our struggling plants and have noticed a huge difference!

In the rows where the soil is quite poor, it has improved the soil health significantly, as well. Case in point, in 2023, I had a good chunk of my dahlias in a row with very poor soil, but I got them late in the season and had nowhere to put them. I was fully expecting them to do poorly. While using the E.P.S.I., they might not be my best set of dahlias, but they have far exceeded my expectations!

A garden with two neatly organized rows of blooming flowers surrounded by lush greenery. The left row has tall, colorful snapdragons in shades of pink, white, and yellow, and the right row features smaller yellow and orange zinnias. A forested area is in the background.

Fish Emulsion

Many flower farmers use fish emulsion to increase blooms. I don’t know if I’m a fan of it, though, as it’s stinky both for indoor and outdoor use. I used it as a flower feed in 2022, and it might have helped, but I feel like the jury’s out on this one. Maybe I didn’t use it often enough? Many people I know swear by it, so I thought I would include it. My favourite mix is the Falling Leaf Westcoast Fish Fertilizer, which I purchase locally from Early’s Farm and Garden Centre.

H-Start Yard & Garden Probiotic Soil Enhancer

2025 is my first year using H-Start, and I’ll never garden without it again.

I used it during seed starting and planting, and I noticed a big difference—most of my seedlings were noticeably bigger than in previous years, even though the timing was the same. The roots were healthier and stronger, and it was so simple to use. You just sprinkle it on, and when you water, it breaks down and works its way into the soil. It works well for both flowers and vegetables and continues to be a game-changer for me in the garden.

Check out my seed starting results below:

Lazy Person’s Compost Tea

This happened accidentally when I wanted to collect water from our high tunnel. I set up a bunch of Rubbermaid totes along the side of the tunnel to collect the rainwater (pictured below), and in one of those totes, I had some leftover manure. I didn’t get time to empty it because it was raining as I was setting up the totes. I didn’t use the rainwater from that collection until a few days later. Any plants that got the water with the manure were significantly further along than those in the high tunnel that didn’t get the “lazy person’s compost tea.”

If you want to make your own quick compost tea, add some manure or worm casings to the bottom of a tote, collect rainwater, leave it for a few days, water your plants, and watch them flourish. See the step-by-step of how I do it in this reel!

A row of plastic containers filled with water and organic matter is lined up next to a greenhouse covered in transparent plastic. The ground is black and there is dense greenery in the background. The scene appears to be part of an outdoor gardening or farming setup.

Related: How to Fertilize Your Seedlings for Healthier Plants

Marphyl

I started using Marpyhl when West Coast Seeds gave it to us as part of our brand ambassador package, and I love it for seed starting. It’s often difficult to find a natural fertilizer that’s strong enough for seed starting, but Marphyl seems to work quite well. Even though it’s an organic marine phytoplankton soil enhancer, it doesn’t have the unpleasant odour associated with fish emulsions. You can also use it on all your plants once the regular gardening season starts.

Slow Release Flower & Vegetable Mix

A normal person would probably mix this granular fertilizer with their soil at the beginning of the season. However, I’m not a normal person. I always forget to purchase it, and I always forget to mix it in, even if I do have it at the beginning of the season. I usually broadcast it on top of the soil at the beginning of the season, in the middle of July, and in the middle of August.

In 2021, I used GardenPro Veggie & Flower (10-15-19+ Micros) with very good results. I couldn’t find it the following year, so I didn’t use it at all. I noticed my plants starting to struggle from the middle of July on, as it seemed the fish emulsion I was using didn’t do enough to help my plants without it.

If you’re in the phase of gardening where if it’s not bought at a big box store it’s not to be bought at all, this fertilizer is the one for you! Of the options in this list, it is the only chemical (non-natural) option easily found in big box stores and online.

Side note: If I were more on top of making compost tea (esp. the lazy person method I outlined above), I have a feeling using that would replace my need for this.

A woman with long hair stands in a greenhouse, smiling and holding a white watering can. She is wearing a light blue dress and an apron with a colorful pattern. Around her are various green plants and trays of seedlings. Strings of lights hang overhead.

What do you think of this list? Do you have any favourite fertilizers? Let me know below!

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