Understand Your Soil
Before planting a new tree, it is important to understand your soil. Your soil type will help determine which tree to plant and how to provide proper care to your tree. Regardless of your soil type, there is a great tree for any situation!
Types of Soil
First, determine which type of soil you have. Soil type can vary widely and the soil in your front yard may be different than the soil in your backyard. It is important to check the soil at your specific planting location.
There are three main categories of soil:
- Clay soil: Drains slowly and feels sticky when wet but very hard when dry. Can be nutrient rich.
- Sandy soil: Drains quickly and feels gritty and light. Has difficulty retaining nutrients.
- Loamy soil: Ideal soil type - nutrient rich, drains well, retains moisture, etc.
To determine the type of soil, use the simple squeeze test.
- Take a small handful of moist soil and squeeze it softly in your fist
- Clay soil: will firmly hold its shape when you open your hand
- Sandy soil: will crumble and fall apart when you open your hand
- Loamy soil: will hold its shape but fall apart loosely when poked
How well your soil drains will determine how often you need to water your new tree. To determine how well your soil drains:
- Dig a hole about one foot deep (width does not matter)
- Fill the hole with water and let it drain out all day and overnight
- The next day, fill the hole to the top with water again
- Place a stick in the center of the hole and mark the water level on the stick.
- Mark the water level on the stick again after 30 minutes and again each hour until the water has fully drained
Poorly draining soils like clay will drain about 1/2 inch per hour.
Moderately draining soils like loam will drain about 1/2 to 1 inch per hour.
Quick draining soil like sand will drain about 1 inch or more per hour.
Clay soil is often mistaken for hardpan as it can be difficult to work with. However, real hardpan is similar to concrete and cannot be softened with water. This means water cannot penetrate the soil to get to tree roots.
Learn more about hardpan.
Rocky soils can also be difficult to work with, but can grow great trees! When planting a tree, remove larger rocks from the soil and add topsoil if necessary to make up for the lost volume. Smaller rocks can be added back into the planting hole to help break up the soil and make spaces for new root growth.
Organic matter like compost can help improve soil conditions, but reusing the original soil to fill the planting hole is best.
Adding a blanket of wood chip mulch on top of the soil around your new tree will provide tremendous benefits and break down to improve soil over time.
Learn more about mulch.
Learn about the specific soil near you by using Soil Web or hire a Certified Arborist to help analyze the soil and make recommendations for your tree.
Soil testing can be done to determine specific soil nutrients and needs.
Learn more detailed information about the importance and different types of soil from the Master Gardeners.