How to Prepare the Soil
Why is good soil important?
For optimum growth, sod needs just four things (in the proper balance)… sunlight, air, water and nutrients. Reduce any of these, or provide too much of any one and the sod will suffer or die. In the right proportions, turf will flourish, providing beauty to the landscape, a clean and safe place to play, plus many other benefits. Grass obtains three of the four essential factors (air, water and nutrients) from the soil, but many soils are less than ideal for growing grass. Some soils contain too much clay and may be compacted. While compacted soils may be great for roads they are bad for grass. If air and water are not available to the roots, it will inhibit the growth of the grass. Other soils may have too much sand. While sand may be beautiful on a beach, too much sand in the soil will prevent water and nutrients from staying in the root zone long enough for the plant to use them. Another frequently observed problem with many soils is the pH. The pH scale measures how acidic or basic a substance is. If the degree of acidity or alkalinity in the soil is too high or too low, it can affect the availability of nutrients to the plant and prevent optimum growth.
How deep should the soil be?
The absolute minimum depth of a quality top soil for a care-free lawn is 4 inches, however for deeper root penetration and the benefits that they bring, the accepted standard is 6 inches.
Can soils be improved?
Not only can most soils be improved, they usually need to be improved to get maximum results with only minimum effort. The knowledge of what is necessary, the amount and availability of materials, immediate costs and time are all factors that typically deter people from taking steps to improve soil. Proper soil improvement and site preparation before any planting takes place will make it easier for the grass roots to penetrate deeply and evenly. Deep roots will make the lawn more drought resistant, use water and nutrients more efficiently and result in a denser and healthier lawn as new grass plant shoots emerge. A dense lawn crowds out weeds and offers greater resistance to insects and disease.
Step 1: Prepare the Site
- Clear the site of all building materials (wood, cement, bricks, etc.) as well as any buried stumps, rocks, stones or other debris that are any larger than 2 inches in diameter.
- Rough grade the entire area to eliminate any drainage problems on the property. This would include sloping the grade away from building foundations, eliminating or reducing severe slopes and filling low-lying areas. A tractor mounted blade and/or box are most often used for rough grading, but if the area is small, it can be done with hand tools. The rough grading will probably uncover more debris that should be removed.
- Initial tilling to a depth of at least 2 inches should be completed prior to adding any topsoil or soil amendments. This will control most annual weeds, alleviate subsoil compaction, permit a bonding of the topsoil to the subsoil and improve root penetration as well as air exchange and water movement.
- Add topsoil to achieve a total topsoil depth of 4-6 inches after firming.
- Apply Bos Sod – Sod Starter Fertilizer. Apply half the bag to the topsoil before laying down the sod and the other half on top of the sod after installation.
- Finish grade the entire site, maintaining the rough grading contours and slopes, with a tractor mounted box blade for large areas or a heavy duty rake for smaller sites.
- Roll the area with a lawn roller 1/3 full of water to firm and settle the surface. Low spots should be filled to match the surrounding grade surface. If time permits, allow area to settle further by applying irrigation.
Step 2: Sod Installation
- Soil & Site Preparation (Discussed Above)
- Measuring & Ordering – Measure the area of your planned lawn. Include these measurements on a sketch of the lawn area, with the length, width, and any unusual features. Schedule your sod delivery after you have completed your soil and site preparation and are ready to install the sod. Prompt installation on the day of delivery is crucial.
- Sod Installation – Install your lawn immediately upon delivery. In hot weather, protect unlaid sod by placing stacks or rolls in the shade. If possible, cover with a moist cloth, or lightly water the unprotected sod. Begin installing sod along the longest straight line, such as a driveway or sidewalk. Butt and push edges and ends against each other tightly, without stretching. Avoid gaps or overlaps. Stagger joints in each row in a “brick like” fashion, using a large sharp knife to trim corners and edges. Avoid leaving small strips at outer edges as they will not retain moisture. On slopes, place the turf pieces so they run across the slope rather than up the slope. To prevent indentations or air pockets avoid repeated walking or kneeling on the sod while it is being installed or just after watering. After installing the sod, roll the entire area to improve sod/soil contact and remove air pockets.
- Watering – Give your new lawn at least 1 inch of water within a half hour of installation. Water daily or more often, keeping sod moist until it is firmly rooted (about 2 weeks). Then less frequent and deeper watering should begin. Weather conditions will dictate the amount and frequency of watering. Be certain that your new lawn has enough moisture to survive hot, dry or windy periods. Water areas near buildings more often where reflected heat will dry the turf.
Caution: During the first few weeks, avoid heavy or concentrated use of your new lawn. This gives the roots an opportunity to grow into the soil and ensures the turf will remain smooth.