Soil

To improve drainage in your soil, fill the bottom layer with lava rocks to a depth of 3-4 inches. To support moisture retention, fill your refrigerator compartment 1/3 full with sticks and leaves. 

Fill your refrigerator with quality raised garden bed soil until the soil level is 2 inches from the top of the refrigerator. Use the information below to help you choose a soil blend.

If you are DIY-ing a refrigerator garden or need to replace the soil in your garden here is an option for a very good store-bought blend of soil.

Our preferred store-bought soil mix is:

  • 1/3 Niu Organic Hawaiian Soil 

  • 1/3 Vermiculite

  • 1/3 Organic Raised Bed & Potting Mix

Bag of NIU Organic Garden Soil featuring a farm scene with a barn, trees, and a tractor.
Bag of Vigoro Vermiculite with yellow and red label
Bag of Kellogg's Raised Bed & Potting Mix with organic plus label, showing children planting in a garden.

If this soil mix is not available to you, you can use this chart to help you create your own soil blend. Start with an organic garden soil that has been amended with worm castings, bat guano, bone meal, fish emulsion, oyster shells or other quality amendments.

Then pick one item from each column to add to your soil blend. You can opt to use just organic garden soil, but depending on your rain and the vegetables you want to grow, it may not be as suitable.

Table comparing peat moss, cococoir, vermiculite, peralite, commercial compost, and commercial cow manure.

We also recommend adding an organic 10/10/10 fertilizer to your soil blend. The numbers on a fertilizer bag represent the percentage of three key nutrients: Nitrogen (N), Phosphorus (P), and Potassium (K), in that order.