Extension > Garden > SULIS > Maintenance > Sustainable Lawn care Information Series > Establishing a New Lawn to Achieve Sustainability > Seeding Rates and Planting Methods - Seeding by Hand or with the Aid of Powered Equipment
Seeding Rates and Planting Methods - Seeding by Hand or with the Aid of Powered Equipment
Hand seeding is most practical where only small areas are to be established.
- First, lightly rake the soil surface loosening at least the top 1/2 inch of soil. This will allow for easier incorporation of the seed into the soil surface helping insure good seed-to-soil contact.
- Next, spread the seed by hand or by using a drop type fertilizer spreader calibrated to deliver the appropriate seeding rate. Whether you use a drop spreader or spread seed by hand, apply half the desired rate in one direction, then spread the second half at a right angle to the first to insure a good pattern of distribution without skips or gaps.
- Follow up with a light raking allowing about 10 to 15 percent of the seed to show on the soil surface. Lightly roll the area to ensure good seed-to-soil contact. A roller such as that used for rolling sod can easily be rented and used for this purpose. Note: Drop spreaders are generally preferred for seeding as they are more accurate due to less influence by windy conditions and differential seed size (i.e., larger seeds are thrown farther than smaller seeds when using a rotary spreader, resulting in uneven distribution of grass species within the area).
Scatter seed using a horizontal back and forth shaking motion.
Seeding rate about right.
Seeding rate too high.
Be careful not to bury the seed too deeply. Seed that is buried too deeply may not germinate. Always gauge depth of planting by the smallest seed in the mix.
For example, when mixtures of Kentucky bluegrass, perennial ryegrass and fine-leaved fescue are used, depth of planting should be determined by the Kentucky bluegrass seed as it is the smallest of those in the mix. In this example, planting depth for all seeds would be about ¼ inch for the mixture. This would be the normal recommended planting depth for Kentucky bluegrass.
Larger areas are better seeded with mechanical devices that can either be rented or performed by a turfgrass professional. One example is a walk-behind machine known as a "slit seeder." These can be rented from local rental businesses by homeowners or used by a hired professional.
Slit seeder undercarriage.
Slits made by slit seeder.
Slit seeding in two directions.
Two weeks post slit seeding.
Two months post slit seeding.
This machine loosens the soil just ahead of a series of discs that cut a groove to a specified depth in the soil. A series of tubes drop down from the seed hopper beside each of the discs. Seeds are dropped through the tubes at a specified rate into the groove and lightly covered by the rotating disc. This allows precise placement of the seed at the proper depth and spacing. Again, it is usually desirable to seed in two directions perpendicular to each, using half the seeding rate in each direction.
Water after seeding.
Once seed is planted, make sure that the soil is kept evenly moist although slight drying between waterings is not detrimental and may even be beneficial. South-facing slopes and other parts of the yard exposed to hot afternoon sun may dry out more rapidly and require additional watering on a more frequent basis.
Moisture is critical once seeds start to germinate. They should not be allowed to dry. After the majority of seeds have germinated you can water more heavily, but less frequently, to encourage deeper rooting.
Be sure that all of the different grasses contained in a mix have germinated before cutting back on moisture. Establishment should take 6 to 12 weeks. A lawn seeded in late summer (mid-August to mid-September) should be usable the following spring.
Mow the lawn once it reaches a height of 2 ½ to 3 inches. Cut no more than one inch off, otherwise you will slow the establishment process. Mowing regularly in this way encourages deep rooting and helps maintain good growth. In addition, where the fast germinating perennial ryegrass is used in the mix, mowing when it reaches 3 inches will help prevent excessive competition with the much slower germinating fine fescues and Kentucky bluegrass.
When seeding in the late summer or early autumn, a preemergent herbicide should not be needed. Postemergent weed control in a newly seeded lawn will have to wait until it's been mowed several times to allow the plants to become well established. Always check the specific weed control product label for how soon after seeding and germination that particular product can be applied to a new lawn without the likelihood of injury occurring. Also, many of the troublesome annual broadleaf weeds that appear during the early establishment period will disappear once a regular mowing schedule has begun.
Using Hand Applied Straw Mulch Cover to Protect Newly Seeded Areas
Grass seedling establishment can often be improved with the use of organic mulches put down immediately after seeding has been completed. The mulch serves as protection for both the seed and the new seedlings. It also provides a more uniform germination and early growth environment. As a result, establishment usually proceeds more quickly and allows less time for weed invasion to occur.
Clean straw mulch applied after seeding.
Turfgrass establishing through straw mulch.
A very common organic material used for this application is clean straw or perhaps hay so long as it is free of weed seeds. Ditch cut hay can contain thousands of weed seeds just waiting to germinate along with the grass seed. Grassy weeds such as yellow foxtail may be present in ditch cut hay. These annual weeds can be competitive, but they do not survive frost. Hence, the desired turfgrasses have ample opportunity to grow and fill in those areas over the remainder of the fall season giving little chance for a similar invasion the following spring. Mowing will also help keep yellow foxtail in-check while the other lawn grasses are continuing to get established.
Grassy weeds such as yellow foxtail (tan color clumps) compete with germinating grasses.
Close-up of yellow foxtail after a frost.
Oat or wheat straw, among others is more commonly used for this purpose. However, that straw can also contain significant amounts of crop seed that can germinate and severely compete with the newly seeded grass. The pictures below show germinated and actively growing oat plants arising from the oat straw used in this case as a seedbed mulch.
Oat seedlings (larger, blue-green plants).
Actively growing oat seedlings (blue-green areas) among smaller turfgrass seedlings (medium green areas).
If allowed to grow too tall before being mowed, it will significantly reduce the survival of the slower germinating Kentucky bluegrass and fine fescue seedling plants. In this case, keeping the oat plants mowed short will allow the other grasses to successfully compete and not be crowded out by the oat plants. Again, be sure to ask for weed-free straw (as much as possible) for this purpose. It will prevent a lot of other weed problems down the road.
These types of mulches are usually purchased in bales. Once opened, straw from those bales can be hand scattered over the surface being sure not to make the layer too thick. After the straw has been applied, approximately 15 to 20 percent of the soil surface will be visible. This will provide the desired protection while allowing enough sunlight through the mulch to encourage seed germination and early growth.
An initial watering to thoroughly wet the area and the mulch is beneficial. From that point, water enough to keep the soil damp but not soggy. Remember, these mulches will reduce the frequency needed for additional water. Hence, be sure to check how moist the soil is before applying additional water. Barely moist is much better than soggy wet.
Leave the mulch in place as it will decompose naturally. Trying to remove it will only disrupt the growth of many of the seedlings, potentially tearing them out and destroying them. If wind is likely to be a problem, staking the straw down periodically over the area will help reduce the tendency for it to be picked up and blown around or away in the wind.
For use of erosion mats to protect newly seeded areas see Erosion Control Mats at the end of this chapter.
For more on seeding the lawn, see: