Garden, landscape and lawn soil testing
When to sample
From the perspective of nutrient availability, soil can be sampled any time of the year as nutrient levels vary only slightly from season to season. A small decrease in exchangeable potassium may occur following a productive harvest, yet difference is unlikely to affect fertilizer recommendations.
Ideally, garden soil is sampled between crops such that corrective fertilizer and lime applications an be made before the next season. Although most people take samples in spring, this is the time when our laboratories and county offices are overloaded with samples. A delay in the return of results may occur. Fall or winter sampling leaves more time for planning and corrective fertilizer management.
How to take garden and lawn samples
Sample from uniform areas. Avoid known soil differences (soil color, texture, slope, limestone, fertilizer, manure) in composite samples — sample them separately. Mix samples to obtain one composite sample in a clean plastic pail (metal pails contaminate the soil with micronutrients) and retain one pint.
- Garden or landscape soil
0 to 7 inches
8 to 10 separate cores samples
- Lawn soil
4 to 6 inches
6 to 10 random subsamples
Plants for which recommendations are given
Fertilizer and lime recommendations are provided according to the following groups:
- Annual flowers and vegetables
- Cool season turf grasses (bluegrass, fescue or rye)
- Warm season grasses (zoysiagrass, bermudagrass or buffalo grass)
For both groups of turf grasses, either a moderate or high maintenance fertilizer program may be chosen.
If you want recommendations for an individual plant (perennials, vegetables, flowers, fruits or landscape plants), check "other" on the horticulture form and write the name of the plant in the blank provided.