Soil is alive. If you just fill your raised beds with cheap "topsoil" from a bulk yard, it will likely turn into a brick of mud after the first rain. You need structure and nutrients.
The Magic 50/30/20 Formula
For best results without spending a fortune, aim for this mix:
- 50% Topsoil: Provides bulk and mineral structure. Cheap.
- 30% Compost: Provides nutrients and water retention. Use mushroom compost or leaf gro.
- 20% Aeration: Perlite, Vermiculite, or even just coarse sand. Keeps the soil fluffy for roots.
What about Peat Moss?
Peat is great for holding water, but it's acidic. If you use a lot of peat moss, be sure to add garden lime to balance the pH, otherwise your tomatoes will struggle.
Calculate Bed Volume
Find out how many cubic yards you need to fill your boxes.
Open Soil Calculator