To help you maintain your “sense of humus” here are a couple ways to test your soil’s texture and structure.
Your soil texture is the proportion of particle sizes (sand vs. silt vs. clay) and the percentage content of each. “Loams” are the best type of soils with around 40% sand, 35% silt and 25% clay. Before you start adding organic material and compost, test the “parent” soil (existing soil) for the percentage mix of these particles. Fill a clear jar a little more than 1/2 full with clean water. Collect soil samples and add enough soil to the water to fill the jar with a little space left at the top. Put on the lid and shake vigorously until the soil is suspended in the water. After a few minutes mark the jar with a sharpie marker for what initially settles at the bottom, this is the sand. Let the jar sit for 24 hours, the next layer will be silt, mark the jar. After another 24 hours, revisit the jar to mark the final layer which is clay. Now calculate the % of sand to silt to clay and compare to the “loam” percentages above.
The physical condition of the soil is the structure. Are there good pore spaces in your soil? Compacted clay soils do not have good pore spaces as an example and have poor structure for root growth, drainage and plant health. Amendments to your “parent” soil will be necessary. Try this……work a coffee can with no top or bottom pushed firmly into the soil about 1 inch deep. Mark the inside of the can every inch from soil level to the top with a sharpie marker. Fill the can with water and wait 10 minutes. If the can drains out before 10 minutes, fill it again until 10 minutes is over. Add the total inches of water that drained during the test and divide by ten to find the infiltration rate per minute. This will give you an idea how quickly or slowly your soil drains and will help you guage the amount of aerating and amending work needed. You want your soil to drain well, yet have moisture and nutrient retention capability…..it’s the old “moist but well drained soil” instruction for healthy plants and turf…..the foundation of horticultural success…..don’t “heave loam with out it!”