Different plants from different environments thrive best in different soils. But how can you determine the most suitable soil composition based on those that you own? Blow, I introduce an excel spreadsheet that will help you do exactly that!

Interface

Below, you can see the interface on the first sheet of the workbook. In order for it to work, you will need to trust the file and enable macro’s (this is required for the button’s click-functionality).

You can select either a plant type or, when you are not sure about the plant type, the environment in which it typically grows. Click the checkbox for which option you would like the calculator for work, and use the drop-down under ‘type’ to select your choice.

For example, below, I selected ‘climate/habitat’ for the selection category, and then ‘desert’ for type.

Once you’ve done that, you will see that a graph has appeared in the box on the right. This graph shows your ideal soil composition, considering six criteria:

1. the ratio organic/inorganic material,
2. the soil aeration (how easily oxygen can make it to the roots),
3. water retention capacity (how much water can the soil absorb),
4. drainage (how easily water can pass through),
5. nutrient content, and
6. pH-level.

Except for the organic/inorganic share, where the ratio is a value between 0 and 1, each criterion ranges from low (1) to high (5).

Now, on the left, you see a number of soil components. Using the up and down buttons beside the input cells, you can add or remove ‘one part’ (i.e. one cup, one shovel) of that particular type of soil.

When you do that, you will see another (dashed) line appear in the graph. This line resembles the characteristics of your current soil composition.

By adding and removing parts of soil that you have access to, you can try to get as close to the ‘ideal’ line with your own unique composition.

Taking our ‘desert-type’ example, I see that I can get pretty close to the ideal soil composition by adding equal parts of sand, perlite, and potting soil.