If you’ve ever wandered down the nursery soil aisle, you know there’s a bewildering array of soils for just about every application you can think of; roses, vegetables, grass. It’s a tribute to the marketing departments of fertilizer giants like Scott that the average consumer can be so overwhelmed by their choice of dirt.
We field a lot of questions from people about what type of soil is best for what application. Is there a difference? Many people are skeptical. But yes, there is a difference. Is the difference all that important? Maybe, maybe not.
When Dirt is Not Just Dirt
Dirt isn’t just dirt. Dirt is dead. It’s just bits of rock ground up very small. Soil is alive, chock full of microorganisms and the minerals plants love. Soil contains dirt, but it also contains small bits of organic matter (decaying plant material) which is where most of the microorganisms make their home.
The best soil combines dirt (not too clay-y and not too sandy, also known as loam) plus at least the same amount of compost. Soil can also be fertilized with an organic fertilizer, usually manure. Manure has a lot of nitrogen, which the microorganisms love, which means they create more of the waste products that plants like.
It sounds more complicated than it is, really.
Soil For Different Applications
If you were starting from scratch, say with a raised bed garden or in new construction, you would get this “perfect soil” blend that we mentioned above. The most common name for it is “garden soil.” This is everything the average plant needs to thrive.
Notice we said “the average plant.” If you only ever bought this type of soil, you would be fine, and you’d never have to read another word on soil. (Except pots. Don’t use this soil in pots.)
But if you have a specific plant in mind, you can mix and match garden soil components to get a blend that your specific plant will like better, especially if you already have some soil in place and you will be mixing with it.
The components are: dirt, compost, and manure. The dirt is either sand (big grains) or loam (medium grains). Small grains make clay, and you do NOT want clay.
Now, think about the plants you want and the soil that’s already in the spot you are adding to.
Grass seed in an existing lawn = dirt (sand) + compost. Why? The sand is for good drainage and letting the seeds root into the existing lawn. The compost is for healthy, sustainable growth.
Vegetables, roses, and flowering annuals into existing garden soil = compost + manure. Why? You already have decent soil, so the compost will maintain that balance and the manure will fertilize it, giving an extra growth boost to ensure good yield.
Top-dressing perennial beds = compost. Why? Growing anything in one spot for a long period of time is going to lead to depletion of the soil unless you add compost to make up for it. You can also add manure, but it’s really better to amend with manure (dig up the soil and mix it in) or you’ll encourage a nice big crop of weeds on top.
With this primer, you’ll be well on your way to choosing the right soil for the right application. But of course, you can always ask us, JK Enterprise. We’re always happy to help.