Fertilizers for Tomatoes – Dome Grown Farms

Fertilizers for Tomatoes

You might have your favorite fertilizers for your tomatoes, but if you don't let me tell you what we've been feeding the Marianna's Peace seedlings this year (2026).

I ran across a great YouTube channel owned by a guy who is an excellent gardener. He also comes up with some homemade fertilizers for his tomatoes and he shares his recipes and his "Before/After" evidence on his videos.

This year I used one of his recipes. You can see the video by clicking the VIDEO button below:

WATCH THE VIDEO

Want my notes?

Here are my notes from watching the video:

M&M (Microbes & Minerals) Tomato Fertilizer Recipe

This "M&M" formula is designed to boost tomato growth by feeding beneficial soil microbes and providing essential minerals like calcium and magnesium.

Ingredients

  • Buttermilk: 1 cup
  • Black Strap Molasses: 1 tablespoon
  • Eggshell Powder: 1 tablespoon (must be cleaned, dried, and finely ground)
  • NOTE: You can SKIP the grinding of the eggshells by purchasing eggshells already powdered. I found some on Amazon. Here's a link if you want to get some: POWDERED EGGSHELLS ON AMAZON
  • Epsom Salt: 1 teaspoon (plain, fragrance-free magnesium sulfate)
  • Water: 1 gallon total (lukewarm rainwater is highly recommended; if using tap water, let it sit for 24 hours to off-gas chemicals)

Equipment

  • Glass blender or coffee grinder (for the eggshells)
  • Large Mason jar with lid (for shaking/mixing)
  • 1-gallon bucket
  • Paint stick or similar stirring tool

Directions

1. Prepare the Eggshell Powder

Rinse your eggshells to remove residue and let them dry completely in the sun or oven. Once dry, grind them into a fine, baby-powder-like consistency using a blender or mortar and pestle. The finer the powder, the faster the calcium becomes available to the soil.

2. Create the Microbe Booster

Dissolve 1 tablespoon of molasses into 1 to 2 cups of lukewarm rainwater. Pour this mixture into a large Mason jar, add the 1 cup of buttermilk, and shake vigorously to ensure they are completely combined.

3. Create the Mineral Booster

In your 1-gallon bucket, combine 1 tablespoon of eggshell powder and 1 teaspoon of Epsom salt. Add the remaining rainwater to fill the bucket to the 1-gallon mark. Stir this mixture for about 60 seconds with a paint stick.

4. Final Combine

Pour the "Microbe Booster" (the buttermilk/molasses mix) into the bucket with the "Mineral Booster". Stir everything together one last time to ensure a consistent blend.

Application Instructions

  • Method: Use as a soil drench. Do not spray this formula on the plant leaves; apply it only to the soil around the plant.
  • Placement: Avoid pouring the mixture directly on the stem; apply it to the soil surrounding the base.
  • Frequency: Apply twice a week during the early growth stages, then once a week as the plant matures.
  • Dosage by Plant Age:
    • Seedlings: A few drops or a small dropper-full.
    • Young Plants: Gradually increase to 1 ounce.
    • Maturing Plants: Increase to 1/2 cup.
    • Large/Established Plants: Use 1 full cup per application.