UNION COUNTY — With the freezing temperatures, many of us are probably not thinking about summer gardens. However, now is the time to start thinking about soil nutrition and taking a soil sample. Soil samples should be taken ahead of the gardening season so if lime is needed it will have time to amend the soil. Proper quantities of nutrients, such as Nitrogen, Phosphorus, and Potassium, and pH are essential to optimum plant growth. Let one of these be out of balance and you could experience many different problems.
Soil pH is how acidic or basic your soil is. Most of our vegetable garden plants like the pH to be around 6.5. In general, our soils around here tend to be acidic and it is not uncommon to find pH values ranging from 5.2 to 6.0. If your soil pH is low you could be wasting your time and money applying fertilizer. Soil tends to bind the nutrients tighter as the soil pH declines. In order to correct a low soil pH, one must add lime. Lime will raise the pH but it does take 3-6 months for the lime to raise the pH. There are quick acting limes available, but those typically do not last as long. Plan ahead and save yourself time and money. A soil sample can give you the exact amount of lime you need to add to your garden.
Soil nutrients also play an important role in optimum plant growth in our gardens. Add too much and you could have excessive plant growth with no fruiting, salt burn, and you could be wasting money. Add too little and your plants will show nutrient deficiencies and stress. In order to know how much fertilizer (or nutrients) to add you need to do a soil sample. The report will give you recommendation on how much Nitrogen, Phosphorus, and Potassium to add. Keep in mind that Nitrogen leaches out of the soil quickly, while Phosphorus and Potassium will bind to the soil and hang around for a while. Many times when we build up our Phosphorus and Potassium to sufficient levels we may not have to add them every year.
So, how do we take a soil sample? Take 10-12 core samples from the garden area in random fashion and combine them in a clean bucket. Samples should be taken about 4 inches below the surface of the ground. Care should be taken not to get organic debris or plant material in the sample. I typically use a trowel or shovel to take my samples. If you have areas that you have fertilized or managed differently you will want to do a separate sample for those areas. After collecting your sample, you can drop it off by your local Clemson Extension Office. The cost for a soil sample is $6.
We have soil sample bags in our office that you can pick up or you can bring it in a clean quart storage bag that we can then transfer over to the soil sample bags. Please be sure to bring in about a quart of soil. Reports are mailed back within about 10-12 days. If you have questions on how to read your report your local Clemson Extension Agent should be able to help. Soil sampling a garden is really a quick and easy process. It helps insure that you have healthy soils to optimize plant growth. Fighting the insects and diseases in a garden can be hard enough, let us help you improve your soil so your garden can be productive this year.
Clemson University Cooperative Extension Service offers its programs to people of all ages, regardless of race, color, gender, religion, national origin, disability, political beliefs, sexual orientation, gender identity, marital or family status and is an equal opportunity employer. If you have questions about soil sampling please feel free to contact Jeff Fellers at the Union Clemson Extension Office (864) 427-6259 Ext: 115.
Jeff Fellers is the Clemson University Cooperative Extension Area Forestry Agent.