Guide to Soil Types
Maine soils vary widely from sandy to clay-like with every combination in between. This can make choosing the right plants for your location challenging. First, try to be realistic as to whether you want to work at preparing your soil to accept a wider array of plants or seek out plants that would tolerate the soil you have. Most gardeners we encounter at Estabrook's choose to amend their soils with organic matter or other natural ingredients to provide drainage, aeration and nutrients, thus widening the palette of plants they can grow.
To determine what kind of soil you have, remove a tennis ball sized amount of soil and place it in the palm of your hand. Squeeze tightly and then gradually release your grip. If the soil stays in a clump without breaking apart, chances are you have a clay based soil. If the soil starts as a clump but begins to gradually break apart you probably have a sand or clay based soil high in organic matter. If the soil immediately starts to crumble you probably have a soil made up of mostly sand.
Remember this is a general test and be sure to test different areas. Soil types can vary greatly due to home construction and other outside influences. Please contact us if you think you need more specific advice.
Whatever your soil type, an application of organic matter is a good idea at anytime, since these amendments are depleted by time and absorption from plant roots. Below you will find a few tips to help you make the most of the soil nature has "dealt" you.
The primary concern with sandy soils is their inability to hold water and nutrients, causing them to dry out quickly and for plants to grow weakly. The following items are commonly added to improve these deficiencies. After each is a rough application rate and preparation tips.
- Peat Moss - Apply 2-4" in the spring and again in the fall, working it into the first six inches of soil with a fork, spade, or rototiller. Since peat moss is a dry amendment that first resists water before absorption, make sure to water the amended soil well before planting.
- Compost - Follow the same directions as peat moss. Compost is in some ways easier and better to work with since the product is usually already moist, is a more renewable resource, and doesn't tend to acidify the soil as much as peat.
- Dehydrated Manure - We recommend that this product should be used in conjunction with either of the previously mentioned amendments since it may have a tendency to burn plant roots in its pure form. A good ratio is 1 part manure to 2 parts compost or peat to 6 or more parts of the original soil. Top dressing within the first 2" of soil can also be done in the spring or fall. Follow the instructions above for incorporating into the soil.
- Composted Manure - See the above instructions for ratios and incorporation into your soil. Composted manure does not have a tendency to burn plant roots like dehydrated manure, but Estabrook's still recommends using it in combination with other amendments. It can be a very rich amendment and used in its pure form, can cause plant growth problems.
The biggest concern with clay soils is their tendency to shed water when dry and to provide too little aeration to plant roots when moist. Dry clay soils will make plant root penetration difficult, while wet clay soils will suffocate plants and encourage certain diseases that thrive in low oxygen soils. Adding amendments will counteract these tendencies and also add the capacity to hold more nutrients. The following list, although very similar to the one for a sandy soil, provides different benefits in clay.
- Peat Moss - Work into the soil at roughly the same rate as you would for sandy soils. In clay, peat moss provides organic matter and helps to create a more porous or "friable" soil.
- Compost - Again, application is very much the same as for peat moss. Compost provides more immediate nutrient levels than peat and is easier to incorporate.
- Dehydrated Manure - See above under sandy soils.
- Composted Manure - See above under sandy soils.
- Gypsum - Gypsum is a natural agent that works chemically with your soil to improve water and air penetration. It is probably best used in combination with one of the other amendments mentioned above. A rough application rate would be 5 lbs to 25 square feet.