Soil Testing:
How To Test Your Garden Soil pH And Identify Soil Types

hole being dug in the ground to plant a Pop Star hydrangea

There are many different types of soil, but what is the best one for bigleaf hydrangeas, like those in the Endless Summer® collection? Before planting your hydrangeas, it’s important to get an understanding of what soil you’re working with, and the soil your hydrangeas prefer. For bigleaf hydrangeas, the best is loam soil. Loam soil is made up of a pretty even mixture of sand, silt, and clay, giving it a great well-balanced texture. Loam soil has good water retention and has excellent drainage, which provides a healthy environment for hydrangeas to thrive.

How To Test Your Garden Soil

To know whether you have loam soil or not, you will need to test your soil. Whether you’re a seasoned gardener or just starting out, understanding the soil in your landscape is crucial to the success of your hydrangeas. Soil testing can help you identify the type of soil you have and the nutrients it may lack, allowing you to select the right plants for your garden and make any necessary amendments to your soil.

Why is Soil Testing Important?

Soil testing is important for a number of reasons. First, it can help you identify the type of soil you have. There are several different types of soil, including clay, sand, silt, and loam. Each type of soil has different properties that affect the growth of your plants. For example, sandy soil drains quickly, which can lead to dry soil and reduced plant growth. Clay soil, on the other hand, retains water well but can cause standing water, which many plants don’t thrive in.

Soil testing can also help you identify the pH level of your soil. pH is a measure of the acidity or alkalinity of your soil. Most plants prefer a pH level between 6.0 and 7.5. If your soil is too acidic or too alkaline, your plants may not grow as well or may even die. This is also important when working with Endless Summer® hydrangeas as they can change color depending on the soil pH. To learn more about that, be sure to watch our video on the science of soil to learn more about changing the color of your hydrangeas.

In addition to identifying the type of soil and pH level, soil testing can also help you identify any nutrient deficiencies in your soil. Plants need a variety of nutrients to grow, including nitrogen, phosphorus, and potassium.

Summer Crush hydrangeas planted in a row in the landscape

How To Test Your Landscaping Soil

There are a few different methods for testing your soil. Whether you choose to do so at home or have professionals do the testing, testing your soil can be done in a few simple steps.

Soil pH Test Kits

Soil testing kits are a quick and easy way to test your soil at home. They typically include a test tube, a pH test strip, and a color chart to help you interpret the results. These kits are easy to use and find as you can pick them up at your local garden center or home improvement store.

To use a soil testing kit, follow these steps:

  1. Collect a soil sample from your garden or landscape. You’ll want to collect samples from several different areas to get an accurate representation of your soil.
  2. Place the soil sample in the test tube and add water according to the instructions on the kit.
  3. Shake the test tube to mix the soil and water, then let it sit for a few minutes.
  4. Dip the pH test strip into the soil and water mixture and wait for the color to change.
  5. Compare the color of the pH test strip to the color chart provided with the kit to determine your soil’s pH level.
  6. If the kit includes tests for nutrient levels, follow the instructions to test for those as well.
The Jar Soil Test

Another easy, at-home soil test is the jar test. With this one you only need a clear jar, a garden trowel, ruler, and calculator.

To do a jar test, follow these steps:

  1. Fill a clear jar with around two-thirds water
  2. Add enough soil from your yard to just about fill the cup.
  3. Place a lid on the jar and let it sit for a couple of days to let everything settle. Sand will settle to the bottom, silt will settle in the middle, and clay will say on top.
  4. After a few days, and you see those clear layers, it’s time to measure.
    1. Measure the distance from the base of the jar to the top of the three layers
    2. Measure the height of each individual layer
    3. Divide the layer height by the overall height to calculate the percentage of each element in your home soil mix
    4. Use the USDA soil texture calculator to figure out what type of soil you have
Professional Soil Testing

If you prefer someone else do this soil test, contact your local university extension office. Many offer soil testing services where you can drop samples off for testing. These offices will provide you with step-by-step instructions on how to take a soil sample and the process for dropping off that sample for testing.

Types of Soil

Once you’ve completed your soil test and you have an answer for what type you’re working with, it’s time to understand what your soil needs from you.

Sandy Soil

Sandy soil means that water and nutrients may run away from the root system of your plants fairly quickly. But that’s not necessarily a bad thing! Some plants, like First Editions® Groovy Grape Butterfly Bush, Cobalt-n-Gold Hypericum, and other drought-tolerant plants can naturally survive and thrive in sandy soil. If you want to plant hydrangeas in sandy soil, amend your soil with compost to help increase water retention and boost nutrient levels.

Silt Soil

Silt soil is a like the best of both worlds. The silt particles are in between the size of sand and clay, so it can retain moisture and nutrients without being so compact that you don’t have any drainage. This soil is great for plants like First Editions® Neon Burst Dogwood and Fiber Optics® Buttonbush that thrive in well-drained soil, but also can tolerate being in standing water. But, if you want to feature hydrangeas in that same garden, you can add organic material like compost to your soil to help improve the soil structure.

Clay Soil

Clay soil is made up of fine particles which make it heavy and dense, meaning that it’s hard for oxygen and water to move around the soil. Many plants have issues establishing roots when planted in clay soil. There are some plants that can tolerate clay soil, like dogwoods, spirea, and even First Editions® Tianshan® Seven-Son Flower, to name a few. However, if you have clay soil and you want to plant hydrangeas, it’s recommended that you amend your soil with organic material like compost to help improve soil structure, increase drainage, and boost nutrient levels.

Loam Soil

Like we mentioned before, loam is looked at as the ideal type of soil for gardens! You’re in luck if you have loam soil as your hydrangeas will naturally thrive in your space. Remember that loam soil is made up of a pretty even mixture of sand, silt, and clay, giving it a great well-balanced texture. Loam soil has good water retention and has excellent drainage, which provides a healthy environment for hydrangeas to thrive.

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