Garden Soil Preparation
Soil preparation is the foundation of your garden and needs to be fertile, well-drained, and have the right combination of soil ingredients. Great soil does not just happen and it does not happen overnight. You need to plan, test, and make changes to existing soil if needed.
There are a few types of soil which gardeners have to work with. There is very sandy, sticky clay (what I have), and others are rocky and shallow. Sandy soils do not hold enough water and in the wind, blowing sand can injure delicate vegetables. Clay soils hold too much water and do not allow enough air to enter the soil. Both clay and sand soils must be modified with peat moss, compost, or other available organic materials. I have had to amend my soil with organic material which can be purchased at most nurseries. If you compost, you are all set with organic material.
Plants need many different nutrients to grow well. If you have gardened for a few years, your plants will tell you what nutrient is in short supply.
Nutrients plants need from the soil include:
- Water and Air
- Boron
- Nitrogen
- Copper
- Phosphorus
- Iron
- Potassium
- Manganese
- Calcium
- Zinc
- Magnesium
- Sulfur
These nutrients are important and the vegetable plant will give you a clue as to which nutrients is in short supply. Plants will show signs of deficiency or excess which will give you direction as to the soil amendments needed.
Before you break ground on a new garden bed, it is a good idea to take a soil test.
To accurately evaluate your soil before you plant, a soil test or have it tested is beneficial. There are kits which are easy to use and inexpensive. Home kits can be purchased at nurseries and garden centers. Soil tests can be done at state Extension Service centers which are generally less expensive that a private lab. These results are typically not available instantly so planning ahead is key. Soil testing is only as good as the sample. Be sure to follow the test kit manufacturer’s instructions or directions from the lab you are using.
Soil test results include recommendations for adding specific amendments. Most extension office will help you interpret and understand the recommendations. The best time to take a soil test are in the spring and fall.
Soil pH is probably the most important factor to assess. It tells you how acidic or alkaline your soil is. The pH range for a garden is from 1-14 with the neutral number being 7. pH below 7 is acidic, and above 7 is alkaline. There are ideal pH ranges for plants so you can imagine if you plant a vegetable which require a pH of 5.5-7 in soil with a pH of 9-10 the outcome will not be favorable. Generally speaking most vegetables require a pH between 4.5-8.0 with 7 being the neutral point. The margin for a good pH is narrow.
Based on your result of the soil test, soil amendments can be added to change your soil pH and nutrient content if necessary.
Tilling
Plants do best when the soil is loose and stays areated. Roots continue to grow during the season and do not stop. Roots and the root hairs do most of the absorption of nutrients for the plant. (I am always amazed at the length of roots I see when it is time for garden clean up in the fall.) There are a couple thoughts on tilling some say yes some say no. I personally till my soil each fall after the growing season. I have a clay type soil and tilling does help loosen the soil. I will also do my soil 
amendments at this time with organic material if needed. Air pockets are created with deep tilling of the soil which facilitates air and water penetration for good plant growth. Air penetration is also important to the microorganisms in the soil that perform all kinds of tasks in creating nutrients for the plants. Once the plants are established I do any loosening (cultivation) of soil by hand.
There are thoughtS about tilling which is not seen favorable by some. Tilling is seen as compacting the soil deep at the end of the rototiller and disrupting the soil bacteria and microorganisms. If you have any worms tilling will also drive them away if they are not killed. If you have soil that is loose and stays that way, tilling disrupts the good worm welcoming environment that already exist and is not recommended. Some gardeners just do not like disturbing the building if micro-organisms and earthworms naturally.
When preparing a new garden tilling is necessary.
Soil Amendments
Almost all garden soils can be improved by adding organic matter to make the soil more workable. Clay type soil which I have needs work every year. Organic matter will loosen clay soil, helps sand hold more water, makes soil easier to dig, and adds nutrients. I learned the hard way by initially adding little organic matter early in my gardening years. My vegetables did not do well mainly because the soil stayed so compact and during heavy rains the water did not drain well. It was only after working in organic matter did my garden begin to flourish.
Some common types of organic additives include:
Plant materials – This included leaves, straw, and grass clippings. Working material into the soil several months before planting will allow time for the matter to decompose. I usually do this in February. I do use a tiller to incorporate the material.
Manure – Composted manure is used and incorporated into the soil well ahead of planting. Fresh manure is not to be used as it will damage the plant and could introduce disease into the soil. I add manure in the fall to make sure plenty of time has passed before spring planting season.
Compost – Compost consists of plant material which has decayed and broken down. I have a compost pile and most serious gardeners will want to have one.
Do not add more than a 4 inch layer of organic material.
Most heavy clay soils benefit from gypsum which helps loosen the clay and makes it more workable. I have a clay soil and it has taken at least every other year amendments to keep the soil workable and has improved the texture, structure, water retention, and beneficial organisms.
Amendments can be added to adjust the soil pH. As mentioned before, the pH of the soil needs to be within a range that will allow plants to access the nutrients in the soil. Once you know the pH of your soil, the addition of lime for soil that is too acidic or sulfur for soil that is too alkaline can be done.
Garden soil is in a state of flux from year to year therefore, ongoing adjustments will need to be done. Plants can deplete the nutrients in the soil, rain washes them away, and eventually the soil will revert back to its natural state. Best practice is using organic matter in your garden whenever you can and the easiest way is to develop your own compost pile. Not all nutrients can be obtained from a compost pile but it is a good start to keeping the pH in check and improving the texture and drainage of the soil.
After completing the steps to properly prepare your soil for planting, gardening might seem anything but easy, but it should get easier each year with proper ongoing soil preparation.
If you missed the first post of this series: establishing a location, check it out here.
“And forget not that the earth delights to feel your bare feet and the winds long to play with your hair.” Khalil Gibran
