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Aug 162012
 

New home site being prepared for seeding. Note the rock and debris piles to be removed.

Remove rocks and debris from area to be seeded.

Large pieces of leftover construction lumber or tree stumps that are covered with soil will eventually decompose leaving depressions in the lawn and can also lead to the fungus that causes fairy ring. Grade the area sloping away from house foundation at a minimum of 2% (¼ inch fall for every 12 inch run) to allow for adequate drainage of water. At this point in the process is a good time to install an underground irrigation system. However, before installing the system, be sure you know where your landscape features such as trees and flowerbeds will be located so the trees will not later interfere with the irrigation system or the flowerbeds will be properly watered. Before planting a lawn is also a good time to control deep-rooted perennial weeds such as quackgrass, Canada thistle and field bindweed.

After properly grading the subsoil, top soil should be added if not already in adequate amounts on the site (minimum of 6 inches). The final topsoil grade should match the contour of the underlying subgrade.

Seedbed Preparation

Add soil amendments such as compost if the soil is low in organic matter. A soil test will tell you whether the soil requires organic matter or other nutrients. Incorporate the fertilizer and soil amendments to a depth of at least 6 inches.

After the tillage operation, smooth the surface with a rake for smaller areas or drag a piece of chain-link fence behind a riding mower or four-wheeler for larger areas. The final seedbed should be moist, slightly firm leaving a one-quarter inch footprint. During this final raking operation, spread a starter fertilizer and rake into the area. A general rule of thumb is to add a starter fertilizer with adequate phosphorus at a rate of 1 lb nitrogen per 1000 ft².

Seeding

Seed the area in two directions to ensure adequate coverage, then rake lightly to place the seed at about a one-quarter inch depth. A metal leaf rake works well. Lightly roll the entire area to ensure good seed-to-soil contact using a lightweight roller. Apply a straw mulch, especially on sloped areas, to prevent erosion and help retain moisture as well as buffer temperatures while the seedlings are emerging. It is not necessary to rake away the mulch after emergence if it was applied at the proper rate.

Post Planting Care

Irrigate the area lightly and frequently to keep the surface moist during the germination process. This may require two to three light waterings each day especially during periods of hot, dry weather. A mid morning irrigation and one at mid afternoon may be enough to keep the surface moist, but an additional irrigation may be needed in the early evening as well. Once the seedlings have grown to a height of 1 inch, the irrigations can become less frequent and the amount of water applied can be increased.

The first mowing should be when the seedlings reach just past the desired mowing height. Do not apply any herbicide to the new seeding until the grass has been mowed at least four times. If seeding was done in the fall, a herbicide application could be skipped since all annual weeds will die during the winter. If perennial broadleaf weeds are seen in the fall, they should be controlled, but still wait the minimum 4 mowings before applying a herbicide.

Sodding

The seedbed should be prepared the same way for sod as for seed. It is also very important that the soil be moist (not wet) at the time of installation to encourage root growth. Sod that is placed on dry soil will have a difficult time growing new roots. Lay sod pieces in a brick-like pattern with edges placed tightly against each other. On sloped areas, place the sod horizontally across the slope and use stakes for steep areas to avoid slippage. Working in long straight lines will help reduce labor and waste. Roll the area lightly after installation to remove air pockets and provide good root-to-soil contact.

Newly sodded areas need frequent irrigation because the grass lacks a root system. An initial irrigation of about one-half to 1 inch should be applied, followed by enough water to keep the soil below the sod moist on a daily basis. For about the first two weeks while the roots are growing, keep checking the soil moisture by lifting up a corner of sod to ensure adequate moisture is present. Avoid traffic on the area for at least 4 weeks to ensure adequate root growth. Sometime during the first year following establishment, a newly sodded lawn should be core aerified to help eliminate any soil layers created between the soil on the sod and the seedbed. Soil layers make it difficult for water and nutrients to move properly throughout the soil profile.

More information about starting a lawn can be found here.

 August 16, 2012