How to Get Your Soil Ready for Planting

Soil is often overlooked. Many of us simply pick a flower, dig a hole, place it in, and hope for the best. This approach can work if the soil is already in great condition, but for most of us, some adjustments are necessary to create the ideal environment for plants to thrive.

So, how can you improve your soil? The first and most crucial step is conducting a soil test to determine exactly what your soil needs. Thankfully, this article will guide you through the soil testing process and all the steps you need to take afterward to improve your soil. Here’s what you’ll find in this article:

• Understanding Soil Discover the fundamentals of the soil we work with. You'll learn how to conduct a soil test and interpret the results. Whether your soil is nutrient-deficient sand, dense clay, or something in between, this section will provide tips on adjusting your soil’s nutrients and pH for maximum fertility. Additional tests such as texture and drainage checks will help determine how effectively your soil absorbs and drains water.
• Amending Soil Explore the best ways to amend your soil, including the use of both inorganic and organic fertilizers along with other methods like composting. You'll also learn about the three primary nutrients in most chemical fertilizers—nitrogen, phosphorus, and potassium (N, P, K)—and how to read NPK labels on fertilizer packaging. If you prefer organic solutions, you’ll find tips for making your own compost and other non-chemical ways to improve soil conditions.
• Soil Preparation Techniques Find out how to prepare your garden bed for planting, including options like rototilling and hand-digging. This section also covers the importance of installing a mowing strip around garden beds to prevent grass from growing into your flowers. You’ll also find tips on advanced soil preparation techniques such as double-digging for high-performance garden beds, like those for roses, and building raised beds in areas with poor soil.
• Mulching Almost every garden can benefit from mulching. It helps retain moisture, suppresses weeds, and often gives a polished appearance to your garden. This section will guide you on how to apply mulch correctly (not too thick!) and how to achieve the look you desire with different types of mulch.

Even if you’re fortunate enough to have healthy, nutrient-rich soil, the tips and techniques in this article can still help you get even better results. Don’t risk it—get a soil test and start optimizing your garden’s soil today.

Understanding Soil

Soil types range from the extremes of arid, nutrient-deficient sand to rocky, nearly soil-free mixtures, and on to dense, wet clay that forms a sticky, shoe-grabbing mass when wet but hardens to a brick-like texture once dry. Fortunately, most soils fall somewhere between these extremes. However, very few homeowners have that perfect ‘rich garden loam’ to work with.

Soils can be amended by adding sand to loosen and dry them, or clay to make them firmer and more moisture-retentive. You can also enrich them with organic materials such as decomposed leaves, twigs, manure, and lawn clippings to improve both texture and structure. Organic matter nourishes any soil type, resulting in better plant growth overall.

Discover how to make the most of the soil in your area by following these helpful tips. The first step is to assess your garden conditions by getting a soil test done.

Soil Testing

Have your soil tested or perform your own tests to determine whether your soil is light and sandy, moderately productive, or heavy with clay. It’s important to test your soil before adding any fertilizers or amendments. This is in line with the old saying, 'If it ain't broke, don’t fix it.' Over-tampering with the nutrients or acidity can sometimes cause more harm than good.

Soil tests provide insight into the nutrient levels of your soil, similar to the nutritional labels on packaged food. They also measure pH levels and organic content—two crucial factors for ensuring healthy plant growth from the ground up.

To get your soil tested, reach out to your local Cooperative Extension Service, which is usually listed under state or county government in the phone book. Ask them how to obtain a soil-testing kit, which includes a soil collection bag and detailed instructions. Be sure to follow the instructions carefully for accurate results. The results may be displayed in a chart filled with numbers, which can appear intimidating at first. However, by focusing on the following details, you can begin to make sense of these numbers:

Only add the nutrients that your soil test indicates are necessary. More is not always better when it comes to plant nutrients. Resist the temptation to add a little extra fertilizer that claims amazing results. Too much of any one nutrient can be harmful, causing toxicity or even plant disease. Purchase and apply only what your soil truly needs, and save the extra money for more worthwhile investments, like additional plants.

Determining pH Levels

It’s always best to choose plants that thrive in the pH of your current soil. If you need to adjust the pH, follow the recommendations below.

• To raise the pH of acidic soils, use ground limestone. Limestone acts as a natural soil sweetener, neutralizing overly acidic soils. For best results, apply limestone in the fall to give it time to dissolve and take effect. The amount you’ll need varies based on your soil conditions. A simple home test kit or a professional test can help determine your soil's pH. Avoid randomly applying limestone, as overuse can be harmful. Always follow the guidelines on the limestone packaging or those provided by a soil test.
• To reduce alkalinity and increase fertility in limey soils or soils with very high pH, incorporate cottonseed meal, sulfur, pine bark, compost, or pine needles. These amendments will gradually acidify the soil and improve its texture. Garden sulfur, when applied according to a soil test, is a reliable option. It slowly acidifies the soil as microbes break down the sulfur into sulfuric acid and other compounds.
• Maintaining your new, improved pH is an ongoing task. Test the soil's pH every year and add amendments as necessary.

Texture Checkup

To assess your soil's texture, perform a simple test using a jar of water. This at-home method is straightforward and provides valuable insights into the composition of your soil.

Collect soil from your garden, taking samples from near the surface to a depth of 8 inches. If you have dry clay, break it up into small particles and mix it well. Place about 1 inch (a bit over a cup) of this soil into a quart-sized glass jar with 1/4 teaspoon of powdered dishwasher detergent. (The detergent won’t foam.) Fill the jar about two-thirds full with water. Shake it for one minute, turning it upside down if needed to fully separate the soil, then leave it undisturbed on a flat surface.

After one minute, use a crayon or wax pencil to mark the level of settled particles—this is the sand. Five minutes later, mark the level of the silt that has settled. Over the next hour, the clay will slowly settle, allowing you to take the final measurement. These marks will indicate the proportions of sand, silt, and clay, revealing the texture of your soil.

Soil with a high sand content (70% or more) is well-drained and ready for planting earlier in the spring. However, it tends to require more frequent watering and fertilization compared to denser soils.

Soil containing 35% or more clay holds moisture well, meaning it takes longer to dry out in spring and generally needs less watering during summer. It can be richer and more likely to support healthy growth with just compost and occasional fertilizer. Compost is essential for loosening clay soil, improving aeration and preventing it from becoming too dense.

Soil that has nearly equal proportions of sand, silt, and clay tends to exhibit balanced characteristics, making it generally ideal for gardening.

Test your soil’s drainage by digging a hole, filling it with water, and observing how quickly the water drains away. This simple test can provide more useful information than any other soil test, revealing how fast moisture moves through the soil and whether it is likely to be too dry or too wet, both of which can be problematic.

If there has been no rain for a week or more and the soil is dry, dig a few holes about 1 foot deep and 2 feet wide. Fill these with water and note how long it takes for the water to disappear. Compare the results with the following scale:

Soil tests may seem like a lot of effort for minimal payoff, but when your soil is functioning at its optimum level, your plants will thrive and bloom beautifully.

Now that you’ve discovered all there is to know about your soil, head to the next section to learn how to prepare it for planting.

Preparing Soil

Fertilizers

If your soil test reveals deficiencies in specific nutrients, follow the recommendations from the testing service to amend the soil. For minor imbalances, organic fertilizers are a good option.

Organic fertilizers typically have a low concentration of nutrients that are released gradually into the soil. While beneficial in the long run, they are not ideal when rapid results are needed or when there's a significant nutrient deficiency. In such cases, synthetic fertilizers are a more effective option.

A blend of both organic and synthetic fertilizers can strike a good balance: Use the fast-acting commercial fertilizers initially, then continue with the slow-releasing organic options in the following years.

Chemical fertilizers are usually formulated with a mix of three key nutrients: nitrogen, phosphorus, and potassium — often abbreviated as N, P, and K. The numbers on fertilizer bags indicate the percentage of each nutrient in the mixture. For example, a 5-10-5 formulation contains 5% nitrogen (N), 10% phosphorus (P), and 5% potassium (K).

The NPK ratio is also displayed on each container of organic fertilizers. Organic fertilizers have lower percentages of each nutrient compared to their inorganic counterparts, meaning that you'll need to use larger quantities to achieve similar results.

You can also buy fertilizers individually instead of in a three-in-one mix. These are useful when you need to address a specific nutrient deficiency. If you're uncertain about how to solve such issues, consult your Cooperative Extension office or the experts at your local garden center.

Other Methods to Enhance Soil

While fertilizers are generally foolproof and convenient, there are other ways to optimize your soil. Check out these helpful tips to improve your garden soil.

• Check with your city or town hall service department for local compost. Often made from leaves and grass clippings, this compost may be free or available at a reasonable price to residents. If you're looking for more options, try the nearest Cooperative Extension Service, which can provide current information, or check with local landscapers and nurseries who may offer composted materials for their clients. Bulk soil suppliers may also sell straight compost or premium topsoil mixed with compost. Don't give up — composting yard scraps is banned in many American landfills, so someone near you may be composting these materials.
• Plan ahead for large quantities of organic amendments like compost, manure, and leaves that may be added in wheelbarrow loads to improve the soil. This will raise the soil level temporarily, but as the organic matter breaks down, the soil level will lower.
• If organic-rich soil settles and exposes the roots of newly planted shrubs or trees, add more soil or organic material to keep the roots covered.
• If your garden is near a building or fence, keep the soil level low enough to avoid contact with untreated wood siding or fencing, which may rot over time.
• When planting around existing trees, shrubs, or perennial flowers, avoid covering the crown — where the stems emerge from the ground — with organic material, as this could lead to disease problems.
• Spade or till a thick layer of compost into moist (but not wet) soil before planting a new garden. If your soil is hard and compacted, break it up first by spading the area. Remove weed roots and other unwanted vegetation before using a rototiller to break the soil into smaller pieces. After the first pass, go over it again in a crosswise direction. While well-tilled soil may look great at first, silt or clay soils may harden and crust after heavy rain. To keep the soil light and loose, regularly add organic matter. Spread a 4- to 6-inch-deep layer of compost (more if the soil is very poor) and mix it in to a depth of 10 to 12 inches. Your soil will appear darker, moister, and more spongy — a dramatic transformation. Since organic matter decays over time, continue adding compost, mulch, or shredded leaves to maintain the texture.
• Consider using spading or no-till systems to preserve the texture and organic content of healthy soils. Once your soil is loose, light, and rich, minimal disturbance helps retain the levels of organic matter. Avoid excessive tilling, which can break up healthy soil clumps and speed up decomposition. Instead of tilling, gently loosen the soil before planting using a shovel, and break it apart by striking it with the back of the shovel. For very loose soil, prepare it for direct seeding by combing it with a hoe or cultivator.

The most crucial step is to assess the soil texture by feel, both before and after any amendments, so you can gauge the changes. Take a small amount of slightly moist soil from several inches below the surface, squeeze it into a ball, and observe what happens as you release your fingers.

Sandy soils, which often have a gritty texture, will break apart easily. To improve sandy soil, spread a few inches of compost and possibly one or two inches of clay, then test again. When the soil improves, the ball of soil will hold together more effectively.

Clay soils, with their smooth and slippery texture, will form a dense ball that is tough to break. To loosen clay soil, add extra compost and coarse sand. Once the soil is lightened, the ball will break apart easily with just a tap of your finger.

Soil Techniques

Preparing a Garden Bed

To properly set up a planting bed, outline the garden's boundaries with pegs and string for straight lines, or use a garden hose for curved shapes. Slice through the sod along your outlined borders with a spade. Then, remove the sod from the entire area. If the ground is rocky, be sure to remove as many stones as you can while digging.

If the soil is sandy or loamy, you might opt for a rototiller instead of turning the soil by hand. For clay and rocky soils, however, it's best to dig by hand first. For smaller planting areas, use a spade to break up and turn the soil manually.

Once the soil has been turned, using a rototiller becomes easier. You can rent a rototiller for the day or hire someone to do the tilling by the hour if you don’t own one yourself.

Next, spread the required fertilizer, soil enhancers, and any pH-balancing chemicals across the area. Once the soil is turned, tilling becomes easier. On the second pass, aim to till more deeply, ideally loosening and improving the soil to a depth of over 6 inches.

If the area is small and doesn't require a rototiller, turn and loosen the soil by hand using a spade. After the initial treatment, apply fertilizers, soil conditioners, and pH-adjusting chemicals at various times throughout the year for optimal results.

Now is the ideal time to add a mowing strip around your garden bed. You can use patio squares or slate pieces placed end-to-end at ground level to prevent grass and flowers from mixing. Other options include landscape logs, poured concrete strips, or bricks arranged side-by-side on a sand or concrete base. The mowing strip should be deep and wide enough to block grass roots from growing underneath or spreading across to the flower bed, and the top of the strip should remain level with the surrounding lawn.

If possible, let the soil remain unplanted for a week or more. Every three to four days, use a scuffle hoe or cultivator to stir the surface 1 to 2 inches deep, eliminating fast-germinating weeds. This will make your weeding tasks much easier throughout the season.

Double-Digging

Double-digging garden beds to create optimal conditions for deep-rooted plants like roses and perennials is a common practice in many renowned British gardens. While a standard rototiller only works 8 or 10 inches deep and can't break up compacted soil beneath the surface, double-digging can.

Double-digging is no easy feat, requiring quite a bit of effort and manual labor. Take it slow to avoid overexertion, or consider hiring a professional landscaper if you have any health concerns.

Start with bare soil, free from grass and other plants. Begin at one end of the garden, removing a strip of soil the depth and width of a spade. Place this soil into a wheelbarrow. Then, use your shovel to turn the soil underneath, which can be one of the toughest parts of the job, and break it up.

An alternative (and sometimes easier) method is to use a garden fork (a large pitchfork-like tool) to jab into the compacted soil, rocking it around until the soil breaks up. If organic matter is needed, this is the right time to add it to the lower layer.

Proceed with the second strip of soil beside the first. Turn the topsoil from this strip into the first trench, adding organic matter if desired. Then loosen and amend the exposed subsurface soil. Continue filling each trench from the adjacent row while loosening the soil beneath. Finally, fill the last strip with soil from the wheelbarrow.

Raised Beds

Raised beds are an excellent option when the soil is of poor quality or completely absent. Made from pressure-treated wood, reinforced concrete, or mortared brick, stone, or blocks, these beds can be any length, but should have a minimum soil depth of 6 inches to ensure proper root development.

By filling some beds with a nutrient-rich loam mixture and others with a lighter, well-drained sandy mix, you can create the ideal soil conditions for a wide variety of plants. Although this may seem like an expensive solution initially, the durability of these beds makes them a worthwhile investment over time.

For vegetable gardens, simply mound the planting rows to a height of 6 to 8 inches and width of 2 to 3 feet. (You can walk in the paths between the rows without compressing the raised soil.) Permanent and decorative gardens can be created in beautiful raised-bed frames made from timbers, logs, stones, or bricks, ranging from 4 inches to 4 feet in height. If you have large building projects, don’t hesitate to seek professional assistance for strong, durable structures.

If using pressure-treated wood, avoid growing herbs or vegetables in your raised beds as it may contain harmful toxins.

Regardless of the garden bed type, adding mulch serves not only as an attractive feature but also as an effective way to prevent weeds and retain moisture. See the following page for more tips.

Mulching

Don't be discouraged by tough soil. With some effort and the right soil amendments, you'll be able to create a flourishing garden filled with your favorite blooms.

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