Your mix would be about 60% peat, which is similar to many bagged mixes, but it would have less perlite than they do, so it would hold a lot of water. You could do it, but I think you'd be better off using half or less of the peat. With that much peat, you could get very compacted soil if you expose them to a lot of rain. What do you want to plant in the mix?

Not necessarily. Ultimately, the density (compaction) of the soil will depend on: particle size distribution (sand - silt - clay) + organic matter content + foot traffic and probably some other factors. tn is right about mixing sand and clay directly, but you didn't say you were adding anything to existing soil, but instead looking for a recipe for raised beds. I am curious what your native soil is like that you'll be building on top of. I think your blend sounds OK. I generally avoid peat moss and vermiculite but only because in my area it's imported from somewhere else and I'd rather use local materials. OTOH my garden isn't the most fabulous, maybe I should use 'em. :-]

The way the particle size distribution of the gritty mix is supposed to work ensures good water retention, but with no or negligible volumes of perched water to affect root health/function. It's important that the small particles be removed to accomplish this lest they filter in between the large particles, rendering the soil supportive of perched water and eliminating one of the most significant advantages of the mix. Another significant advantage is the aeration inherent in a well-made gritty mix, which would also be a casualty of neglecting to ensure the sizes of the particles are appropriate. If you don't screen the particles, what you end up with is a mix that will perform like a lot of other mixes, and whose only essential variance from most other mixes would be its structural stability, a derivative of the fact that it has a 2/3 mineral component and the organic fraction (bark) breaks down very slowly. This is one of the less significant attributes of the soil though, because inevitably a plant needs repotting long before there would be even a hint there was a hint the soil had structurally degraded. In fact, with a 2/3 mineral fraction, even if the entire bark fraction was to break down or gas off, the soil would still be perfectly servicable. I don't think I've ever really listed the attributes of the gritty mix, so: A) No or very little perched water - the most important (root health) B) Excellent aeration (root health) C) Extremely forgiving and easy to grow in D) Adjustable for water retention E) Serviceable indefinitely - won't collapse (root health) F) Easy to make, once ingredients are located & you're set up to screen I love to see people using it, but I have to be honest. If you can't find the ingredients or suitable substitutes, or don't want to screen them, I don't think it's a good investment of time/effort to make something that will perform similar to a from the bag mix. More important than a recipe, is the concept. The gritty mix is simply the best way I've found to implement the concept described in the thread I'll link to below. I honestly feel that an understanding of the information in the thread represents the largest forward step a container gardener can take at any one time. Root health is often overlooked or given short shrift; but it's very important to realize that a healthy plant is impossible w/o a healthy root system. Roots are indeed the heart of the plant, so it pays to keep them happy. ;-) Best luck. Have fun at the party! Al Here is a link that might be useful: Learn about soils .....

It replaces peat in the mix. It purportedly is more "sustainable" than peat. Dan