We use “Mel’s mix” recipe from the All New Square Foot Gardening book for our raised beds. Because we were concerned about lead (it’s very common in New England soils) we wanted to build raised beds and put in fresh soil for our vegetables.

ingredients

I used a combination of composted cow manure, lobster compost, and bulk compost from the city (composted yard waste). This will provide organic matter and food for our plants.

Vermiculite

Followed by equal parts of agricultural grade vermiculite and peat moss. Vermiculite, a natural mineral (mica rock), holds a tremedous amount of water because it’s flaky and has a lot of crevices. Mel Bartholomew recommends a looser, coarser grade vermiculite to make the soil more friable. I found this grade of vermiculite in bulk (6 cubic foot bags) at a specialty greenhouse store; it is not normally sold at nurseries and garden centers. Peat moss, which is made of decomposed plant material, is supposed to make the soil lighter and more water retentive.

mixed together

I mixed my three ingredients together and generously sprinkled with water. The vermiculite and peat moss, which started out very dry and dusty, soaked up water like sponges. Each bed took in about 40 gallons of water - over a gallon of water per square foot. Good thing I used water from our rainbarrels (which consequently got emptied real fast).

My soil mix is now very loose and crumbly, a big improvement from the rocky and clay soil originally in our front yard. I can’t wait to start planting!