Late summer and fall are great times to germinate seed, the temperatures are perfect, and you do not need to compete with weeds and crabgrass like you do in the spring and summer. Even the best professionals have a hard time keep these things out in the spring.
To renovate your existing lawn, or to scrap the entire thing and start from scratch, can be a difficult decision. If your lawn is completely overrun with weeds, or has other problems, you will have to fix those first.
The newly seeded spots needs as much moisture as possible until germination. If you follow these steps and keep the new seed from drying, you will find success.
1. Get rid of the weeds.
The most effective way to eliminate existing weeds and turf is with non-selective herbicides that contain the active ingredient glyphosate (Roundup, or one of the generic brands that is much cheaper). Other non-selective herbicides include glufosinate (Finale) or the herbicidal soap formulation Scythe. Don’t walk on the grass until the product dries on the leaves.
Most of these products will allow you to seed in 7 days or so. Read the label of whatever you are using. Make sure you don’t apply a selective lawn weed killer . Most of those will keep your seed from germinating for 3-6 weeks.
If the whole lawn is weeds, spray everything. If only a few patches exist of stubborn weeds , spray only those weeds. You will see dying and yellowing soon. Once the weeds are dead, mow the area you are renovating down as short as you can just prior to renovating. This will ensure the seed will make soil contact.
2. Fill in any holes or low spots.
Take care of holes before you replant. Now is the time to eliminate low spots and take care of other drainage problems.
3. Amend the topsoil you have left .
Biosolid organic fertilizers are inexpensive and add organic matter to the soil
Ph adjusting products like lime or Solucal to raise PH if needed
Gypsum or Solu-cal S to help condition clay soils
Any quality animal manure based organic fertilizer
Sandy soils can be amended by incorporating a small amount of clay or organic material to enhance water- and nutrient-holding capacity. Add high-phosphorus starter fertilizer with about 1 lb. N/1,000 square feet and/or pH modifiers such as lime or Solucal based on information from your soil test.
4. Pick the right grass.
The species and variety you choose will depend on:
What quality of sod you expect.
How much work you want to do to maintain it.
How you plan to use it.
Sun and shade.
Resistance to insects and diseases.
Stay away from cheap blends of seed. The bargain from the garden store is no bargain. In this world you get what you pay for , and it is no different in grass seed.
Stay away from mixes with Annual grasses , Noxious weed content , unnamed varieties of seed , and low germination percentages. Usually any mix with the words quick , fast , contractors , and tough are products you might want to stay away from as they are usually low end. Remember, if it is less expensive than all the others , you probably don’t want it.
5. Prepare the soil.
You need to somehow rough or prepare the soil. You can use an aerator or a slice seeder. Both of these can be rented at most rental shops. This time of year they are popular so reserve them early.
If you use an aerator , don’t be afraid to really open the lawn up. Go in 2-3 different directions when pulling plugs. Really beat the area up.
If you use a slice seeder , go half rate in 2 directions then use a spreader to go over the barest areas again to help get a uniform look.
Make sure you seed at the right rate . The larger the seed, the higher the seeding rate. Studies show that there is no benefit from seeding more than the recommended rate. Excessive seeding rates create too much competition between the seedlings. Seeding at the correct rate or slightly lower encourages tillering – lateral spreading of the grass plants. (Sometimes if conditions are less than ideal, a higher seeding rate may be justified.)
Use a rotary “spin” spreader at half of the recommended seeding rate. Then apply the seed in two different directions at right angles to each other. This assures more uniform coverage. It is also easier to be lighter and go over it twice then it is to run out of seed ¼ the way though.
If you are reseeding small patches or around mailboxes and corners, the garden weasel is a great tool. It is a very versatile tool every gardener and professional should own. It quickly roughs small areas and tight spots to allow you to make good seed to soil contact. If you don’t own one, you should.
6. Lightly rake in the seed.
In the bare spots ,mix the seed and soil so that the seed is covered no more than 1/16 of an inch or so. I like to use the back edge of a plastic leaf rake without pressure to incorporate it.
7. Roll the soil.
Only roll if you have a lot of bare spots as opposed to grass you renovated. Light rolling assures good seed-to-soil contact needed for the seeds to take up water and germinate. I usually don’t even fill it with water , using only the weight of the roller. It usually works fine.
8. Mulch large bare spots.
Use weed-free straw or marsh hay to conserve moisture and help prevent erosion. (Avoid pasture hay as it is often loaded with weed seeds.) Other effective mulching materials include products made from wood fiber, paper pellets, and other kinds of erosion-control blankets. Products made from a combination of pelletized paper and water-absorbing gel such as PennMulch are highly effective and hold water better . They are also green , and won’t require rake when done. PennMulch even has a starter fertilizer on it already.
Erosion blankets are great when you have slopes to protect. After seeding , you roll the erosion blanket out and staple it down. The grass grows right up through and the blanket decomposes. No mess and most are green also .
9. Water , water, water.
New seeds and young seedlings will quickly die if allowed to dry out. Keep seedbeds moist at all times until seeds emerge. This is the single most important aspect of seeding. Water only enough to moisten the surface. Do not over water causing runoff. Gradually reduce water after emergence to encourage deeper rooting. Once grass covers about 50-percent of the ground, the surface should be allowed to dry.
About 4-5 weeks after seeding, apply about 1 lb. N/1,000 square feet. This is the standard setting on most Fertilizer products. This will increase shoot density, color and the seedlings’ ability to withstand diseases such as rust.
Once more than 60 percent of the grass reaches the recommended mowing height (at least 2 to 3 inches), start mowing. Mowing encourages lateral shoot development, increases stand density and helps the turf out compete weeds. Make sure your mower blade is sharp. Dull blades will tear young seedlings from the soil.
Once you’ve Mowed the lawn twice , it is usually safe to use weed control products again. Be careful because you may still have young seedlings that will be prone to injury.
12. ENJOY YOUR LAWN.
You worked hard for it, so use it for picnics , baseball, or whatever you like. Its there to be used.