Ideal Garden Soil Mix

While there are many companies that sell garden soil and pre-made soil mixes for your garden, the best blend is always the one you make yourself. The ideal garden soil mix is made up of three main components compost, peat moss and vermiculite.

The Master Gardener who popularized the Square Foot Gardening method, Mel Bartholomew recommends a ratio of one-third of each ingredient mixed well. He calls this mixture, “Mel’s Mix” and it is truly an excellent blend of soil for vegetables of all types. You can get Mel’s book at amazon.com: All New Square Foot Gardening, Second Edition: The Revolutionary Way to Grow More In Less Space

Peat moss aids in helping your garden soil become lighter allowing for greater root function and aids in water retention as well. One of the first things you should know about peat moss is that it is sold in compressed bales that double in size when opened and mixed. So if your calculations for your garden size requires four cubic feet of peat moss in the mix, one 3.9 will give you close to eight cubic feet.

Calculate your measurements based on the amount of material in the bags, not on the number of bags used. Be careful in pouring it as peat moss is dusty and can easily blow away in the slightest breeze.

Vermiculite is a white almost Styrofoam like material that will help your soil in the same way the peat moss does in keeping it light and airy. Vermiculite will also aid in water retention. Some people use Perlite instead of vermiculite. The drawback to perlite is that it will float to the surface of the mix when it rains or when you water your garden. When it does dry up, it will blow away. Vermiculite stays in the mixture. And, like peat moss, it is dusty and will easily blow away.

Compost is the foundation of all soil mixtures. It is from compost that your vegetables will get 100% of their nutrients. The peat moss and vermiculite, though helpful in the blend, have no nutritional value. You have to be aware of what components make up the compost in the bags you are purchasing. Ideally, there should be five different types of composting materials in the bag. Many stores will sell compost made up of two or three components.

You want compost from five (or more) different sources so that your vegetables have the greatest chance at getting the combination of nutrients they need. Note, these are from five different sources, not five different companies making compost from the same sources. Check the side of the bag for a description of the contents or make you own compost.

Excellent sources of compost include:

 

One rule of thumb for using animal manure for compost is that if the animals eat meat, do not use their manure. All five (or more) of these compost blends should be mixed together to come up with the one-third part of your garden soil mix.

A word of caution about using local municipality compost: There are many cities that take your land waste and compost it, then sell it back to you dirt cheap. (Pardon the pun.) While the cost is reasonable you never know what kinds of weed seeds or chemicals from treated lawns have leached into that compost. Avoid it if you can. Mix the three components together on the ground, use a tarp to keep it all, with a rake or a hoe and fill your garden with it.