The kind of soil in your garden can help you determine the best plants to grow, according to experts.
With a unique blend of minerals, organic and inorganic matter, soils fall into one of four general types — clay, sandy, loamy and silty — based on the combination of those ingredients. All four soil types are found in Maine.
Matching soil type to seeds gives you a head start when it comes to growing flowers, vegetables or trees. Each soil type provides the conditions favorable to certain plants and what does well in one type will refuse to grow in another.
“It can be very site specific,” said Gary Fish, horticulturist with the Maine Department of Agriculture, Conservation and Forestry. “There are tools out there to help you match a plant with what will work in your soil.”
The first thing that needs to happen is a soil test, so you know what you are working with.
Soil testing kits are available from any county office of University of Maine Cooperative Extension.
The kits come with instructions on how to take the sample, how to pack it up and where to send it. There is a $20 fee for each sample submitted and it can take around two weeks to get results.
If you don’t want to send soil out for testing, Fish said soil survey maps are available from state soil and water conservation districts, the Natural Resource Conservation Service at the United States Department of Agriculture or from the University of Maine.
Here are the four soil types and what grows best in each.
Clay
It’s hard to confuse clay soil with anything else. It’s lumpy and sticky when wet and hard as concrete when dry. It has poor drainage and can be difficult to cultivate. But it’s not all bad. Clay soil is often rich in nutrients.
Fruit trees, ornamental trees and shrubs thrive on clay soil. Maine summer crops like corn, melons, tomatoes, beans, peppers and zucchini can also do well in clay soil.
Sandy
It’s not going to feel like walking on a beach, but sandy soil is gritty. It drains quickly and easily and what nutrients it does contain can be washed away during periods of rain. To give the soil some help, it’s a good idea to add organic amendments like compost or peat moss and mulch after planting to help it retain moisture.
Root crops like carrots, parsnips and potatoes like sandy soil. So do above ground crops including strawberries, peppers, corn, squash and tomatoes. Flowers grown from bulbs and shrubs are also good choices if your soil is sandy.
Silty
It can be enjoyable to hold silty soil in your hands. It is often described as feeling soft and soapy. It’s full of nutrients but does not always drain well. Mixing in some compost can help it drain.
Most vegetables do well in silty soil. Good choices are shallow-rooted crops like lettuce, onions or broccoli. Peas and beans also do well and, since they naturally add nitrogen to the soil, will help build that soil up. Moistures loving trees like willows, birch and dogwood do well in silty soils.
Loamy
If you have loamy soil on your property, you have won the soil lottery. It’s the equal mix of sand, silt and clay and it’s ideal for growing crops. It’s going to feel finely textured and slightly damp in your hands.
Loamy soil has good drainage, retains moisture and is full of nutrients. Most vegetable and berry crops are going to do well in loamy soil.
It’s a good idea to rotate fruit or vegetable crops, mulch, add compost and plant green manure crops like clover, beans or buckwheat to keep the soil healthy and not deplete it.
“It’s likely you will only have one type of soil where you are planting,” Fish said. “But if you have a [larger] garden you may have variable conditions so you want to take a look for any obvious differences before planting anything.“
