Sample To The Proper Depth:
If the area to be sampled will be rototilled or turned under before planting you want to take a soil sample from the tillage depth. This depth is usually 6-10 inches but could be greater. The tillage depth is important because this is the depth that you will be able to mix in the needed limestone before planting/seeding.
A sample from the top 2-4 inches of soil is satisfactory. Thatch, grass, and other debris should not be included with the soil sample. Please remove this debris before placing soil in the zip-lock bag or container.
Established Tree/Small Fruits, Landscape Trees/Shrubs, Annual, Perennial and Bulb Gardens.
A surface soil sample from the top 8 inches is satisfactory. For deep-rooted trees, shrubs and fruit crops a sub-soil sample taken from the 8-24 inch depth is often taken in addition to the surface sample. Deep-rooted plants depend on soil at these depths for nutrients.
Compost, potting mixtures, topsoil piles.
Each batch of soil/compost should be sampled separately. Be sure compost, potting mixtures or soil has been thoroughly mixed.
Obtain A Representative Sample:
Each soil sample should be a representative sample consisting of the soil from cores taken randomly at several places across the garden, lawn, etc. This should minimize any spot in the area, which is non-uniform to the overall area. Walk diagonally across the area to be sampled and take a core from 10-15 random locations spaced evenly apart over the entire area. Each core taken from the area to be sampled is placed into the clean plastic pail. When all cores are obtained mix them thoroughly then remove two 8-ounce cupfuls of soil and place both of these in a single clean plastic bag/container and identify it with a marker (i.e. #1, letter A, etc.).
How Many Samples Are Needed:
In most cases only one sample is needed for a single lawn, garden, etc. This holds true as long as the soil texture and previous limestone and fertilizer applications have been the same. A separate sample should be taken from areas where this is not true, where problems exists, soil types are different or where plants with different pH requirements are growing or will be grown.
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