Soil Testing

Those interested in having their soil tested may do so through Virginia Tech.  There are soil test kits available from the public libraries in Loudoun County.  Basically, the kit consists of a small cardboard box and instructions.  You only need one kit per parcel of land, the idea is to take samples from different parts of your property and mix them together, dry the soil and send to Blacksburg for testing.  The program is run through the VA Cooperative extension in partnership with Virginia Tech.

Soil testing is useful for obtaining information on what is going on with your soil, especially prior to undertaking a large planting or establishing a vegetable garden.  The soil is alive, it contains micro and macro organisms, water, and minerals.  Organic gardeners focus on feeding and building their soil, which in turn provides nutrients for plants within their micro-habitat.

I mainly wanted to test for how much organic matter was in my soil, especially since I will emplace a raised bed garden in Spring of 2019.  I took four soil samples from different parts of my parcel of land, digging down several inches and placing the freshly dug soil in a bucket.  All four samples went in the same bucket.  It is better to use a bucket that has not contained organic matter or fertilizer in order to not skew the results.  Then, allow the soil to air dry over a period of days.  Since this is Virginia clay soil, it takes longer to dry than you would expect.  After the soil air dries completely, follow the shipping instructions to send the sample off to VA Tech.  

A copy of my soil report is below.  Two things jump out: my soil is low in potassium and I need more organic matter.  I was actually surprised and pleased with the range of the ph level and calcium level, the report in general shows that my soil is not in the dire shape I thought it would be following the recent (12 months) home construction.  After studying the report, I have taken two active steps: continue to add organic matter-I would like to reach levels of five pct organic matter within 36 months.  Also, I have made a concerted effort to compost more banana peels to boost the potassium (K) level.  Info on interpreting soil test reports can be found here.  

Understanding pH and NPK

Quick shorthand for understanding pH...it is essentially a scale of acidity (sourness) and alkalinity (sweetness).  The scale is from 0 (highly acidic) to 14 (highly alkaline).  On such a scale, what is the optimum range for plants?  Of course, around 7.0-plants enjoy balance, like most organisms in nature. 

The major nutrients for plant growth are nitrogen (N), phosphorous (P), and potassium (K).  Plants contain a lot of nitrogen, it is essential to their leaf and stem growth.  Phosphorous fuels root and flower growth, while potassium strengthens plant tissue and helps plants fight disease.