When is the best time to take soil samples?
Take a soil sample a few months before embarking upon any new garden work – starting a vegetable garden, putting in a flower bed, or planting perennials. Sampling well in advance of planting will allow time for applied soil amendments to begin making the desired adjustments in soil pH or nutrient levels.
Sample established areas – lawns, trees, shrubbery, and other perennials – at any time of year; however, an ideal time to take samples is when the garden season has ended in the late summer to early fall. Sampling in the fall allows time for corrective pH and nutrient management before new growth starts in the spring. Fall sampling also avoids a sometimes busy spring period at the Soil Testing Laboratory, thus avoiding delays in getting your soil test results.
If an established area shows abnormal growth or plant discoloration, take a soil sample right away. For areas recently limed or fertilized, delay sampling at least six to eight weeks, otherwise your sample will not reflect the changes you are making.
Can samples be taken when soils are wet?
Soil moisture does not affect the test results since samples are dried before they are analyzed. However, extremely wet soils are difficult to collect and mix. Therefore, allow soils to drain before sampling. Soils too dry are normally hard to get to the right depth.
A soil sample is a composite of numerous sub-samples, so a soil that is too wet will be impossible to mix together. As a rule, if the soil is too wet to work, it is too wet to sample. Another way to judge is to squeeze soil into a ball. If it easily breaks apart, then the soil can be sampled.
How often should a soil be tested?
A soil test should be conducted if fertilizer is going to be applied or when problems occur during the growing season. Once every year is recommended when nitrogen fertilizer is applied, and at least once every three years if P and K are concerned.
Buy your own soil testing products.
Before we go on, let’s see what you learned about when to take a soil sample!