Overseeding Your Lawn

Sep5th 201211 comments

Overseeding for better greening.

Over seed your lawn for thick green grass

When you think lawn care, spring may be the first thing that comes to mind, but the fact is back-to-school is perhaps an even better time to treat your lawn to some TLC. Fertilizing, compact aeration, composting and compost tea all are excellent ways to help your lawn looks its best, but perhaps the most important fall activity is to thicken your lawn by “overseeding” with new grass seed. Yes, a thicker lawn looks better, but the real secret is that a thicker lawn helps crowd out weeds naturally, without resorting to chemical weed killers.

Why do it now.

Back to school is always a little crazy, but if you can squeeze in a couple of hours, here are a few reasons why late August through September is the best time to grow new grass seeds and get that thick green lawn that will be the envy of your neighborhood. While daytime temperatures are on the decline, below the surface the soil retains its warmth – and warm soil helps seeds germinate faster. Back-to school season also brings more rainfall – not great for football, but super helpful for seed germination. Cooler temperatures also reduce insect infestation and disease. And last but not least, weeds don’t germinate during cooler fall days, so your new grass won’t have to compete with new weeds.

How to Overseed Your Lawn

  1. Mow at the lowest possible setting. Use a grass-catcher if you have one, lumps of cut grass will interfere with new seed germination.
  2. Use a grass rake to remove all dead grass and twigs - ensuring good contact between the new seed and soil.
  3. If your lawn soil is compacted (hard to pierce with a shovel or spade) have the lawn aerated, allowing moisture reach the seeds and roots. You can rent a DIY machine, or call Mahoney’s Safelawns and we’ll do it for you.
  4. Spread a high quality seed for a more disease-resistant, drought-tolerant, attractive lawn. Note: overseeding uses half the seed as new lawn seeding.
  5. Apply a quality seed starting fertilizer to provide the phosphorus needed to establish strong roots.
  6. Spread a 1/2-inch layer of compost over the seed –– this is important to improve the soil and will help keep moisture near the seeds.
  7. Water consistently. Grass seeds will absolutely die if they’re allowed to dry out, so your number one job is to keep them moist for at least 3 weeks. Watering should be shallow — getting the top 1/4 inch wet is enough — but you may have to water twice a day especially if it’s hot. Warning: Allowing new seed to dry out for even a day or two can ruin the grass seed you just spread.
  8. After 3 weeks, you can water less frequently but more deeply.
  9. Do not mow until the old grass reaches 3 inches.

Got Bare Patches? Seed Now, Too

  1. Remove all dead grass roots and debris with garden rake or cultivator.
  2. If your soil has the consistency of clay, spread some compost over the area. If your lawn is compacted, do compact soil aeration.
  3. Smooth with a rake or smaller tool, like your hand.
  4. Sprinkle a modest (not too thick) layer of premium grass seed over the spot.
  5. Add a quality organic or traditional seed starting fertilizer.
  6. Gently tamp the seed and fertilizer down so it doesn't easily wash away when you water.
  7. Apply a thin (1/4 inch) layer of straw, sifted compost, or soil-less growing medium as mulch.
  8. Water at least daily to keep the seeds constantly moist for 3 weeks, as you would for overseeding the whole lawn.

Yes, it looks like a lot of steps, but overseeding is not rocket science, doesn’t take all that much work and really isn’t very expensive. Plus year after year you’ll be rewarded with an easer to maintain, more beautiful lawn. One final note: don’t procrastinate –– new grass roots need time to establish before frost, so for best results make sure to overseed before mid-October. Questions? Stop in to any Mahoney’s – we’ll talk you through it.

Now let's hear your fall lawn care secrets.

Got any fall lawn care tips or helpful suggestions that you'd like to share? Leave a comment and let us know your recipe for successful fall lawn care.

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What if your lawn has a lot of crab grass in September?

My lawn looked really good in May and June, but by mid-August, I couldn't keep up with the crabgrass simply by pulling it (we don't use any chemicals on the lawn).

I'm ok with going over the yard with a de-thatching rake and aerating it, but I am not sure if the crabgrass is going to cause a problem with getting the full benefit of over seeding. I'm sure it's better than doing nothing, but my question is whether there are additional steps that you think are required for areas that include higher percentages of crabgrass?

Could the grass seed germinate and sprout in the spring and grow strong enough to help crowd out the crabgrass in the late summer? Could the new grass withstand an application of an organic crabgrass preventer in August next year?

One of the best things you

One of the best things you can do to keep crabgrass down organically is to keep your lawn growing thick and healthy. That being said now is a good time to get seed down because that crabgrass is going to start dying off when we get into colder weather. But now is a good time to throw down the seed right over the crabgrass, take advantage of the warm soil temperatures it will give quick germination, you may need to come back a little later with a second application to get some of those spots you may have missed because of the crabgrass was so thick. Also be sure to apply an organic fertilizer at this time, it will help the new seed as well as the established turf. Fall is always a great time to feed your organic lawn, what doesn’t get used gets stored up for early spring. Something else you should think about this time is your soil ph. If you’re acidic add some lime or Mira cal to change your soil to a neutral ph. It’s said that crabgrass doesn’t like a neutral ph and it thrives in an acidic soil.

As far as organic crabgrass control don’t neglect what I said above. As soon as you let your lawn go dormant or even stress in time of drought like this summer you run the risk of the crabgrass taken over. Now there’s also the corn gluten meal out there but it has to go down at the right amount. You need to use Jonathan green corn gluten meal because that’s the only one that is straight corn gluten. Organic will have corn gluten in there lawn booster but it makes no claims as a weed preventer (it’s only in there for a nitrogen source). Now Jonathan green gives two application rates on the back and the ``heavy ‘’ rate should be used if you seeking weed control. Don’t neglect this because a little won’t do a little crabgrass control it will only feed your lawn and the crabgrass. Another bad thing about the corn gluten meal is the cost may be going up next year, due to the drought in the mid west this year the industry is talking that prices will be going up. There is also another organic weed killer that comes in a liquid form that is put out by Whitney farms and Bayer but it doesn’t work on crabgrass though it is very affective on a lot of others out there.

The whole hand pulling is sometimes tough though if you keep the turf growing good it will choke out the crabgrass. Crabgrass needs sunlight to germinates and it needs to be touching the soil so try keeping your turf a little longer if you’re not doing that and keep it healthy like I said before. Good luck and if you need any help you can talk to b k or mike in the Chelmsford store.

Overseeding under extreme drought conditions

We are in eastern Kansas 40 miles SW of Kansas City off Interstate 35. We have a one acre front lawn of tall fescue that was 30% lost due to the extreme drought this year. This is the second year of drought in this area. There are bare patches and large areas of varying shape that are bare. Varying weeds and crabgrass are growing on the bare spots. This is not a flat lawn. It slopes 300 feet down to our house, and part of the driveway has a steep slope to the edge of the property. How would you plan for repair and renovation of the lawn? We are not prepared yet to go to large areas of ground cover or fancy gardens replacing parts of the lawn. If the midwest drought continues a few more years, then there may be no choices.

We used to live in Bedford, MA, so we are very familiar with Mahoney's. Thank you.

overseeding under extreem drought conditions

It sounds like your seed is a good choice, that is tall fescue is very drought resistant. Some varieties will vary and I’ve had great luck with Jonathan greens black beauty around here. One thing I should mention here is any lawn is only as good as its roots, which means it needs a good few inches of rich soil. Around here we see a lot of what I call builders delights. That is the builder comes in takes all the loam and leaves an inch behind for your lawn so there’s nothing underneath except hard pack clay or sand. Don’t let anyone tell you any different. The better your soil, the better your root growth, which means the better your drought resistance. I have anywhere between 6- 12in. of compost in my back yard under my lawn and I can tell you it makes a difference.
There’s also a couple products on the market that are what I call a wetting agent we carry one called organic water wizard www.uwaterless.com this stuff actually pulls water and morning dew into the soil and will cut you watering in half. This may be something to look at if you go under watering bans. I’ve used this in small areas and it works very well but it can get expensive if you doing large areas like 20,000 squ. Ft. or more.
Good luck;

New lawn

I started a new lawn about a month ago, I tilled the dirt, added horse manure tilled that all in but I had to stock pile a load of manure while I got the dirt ready, and then I spread it, but in the area I piled the manure the grass wouldn't germinate. I realize it is because I left to much manure in that area. So I spread out a few wheelbarrows of dirt and reseeded. I want to make sure it takes this time, so do you have any suggestions? I saw for patching lawns you suggest spreading hay. Would that be a good idea for my situation?
I think the main problem was the manure dried out faster than the rest of the lawn. The bare area is about 200 sqft

Ya it sounds like the manure

Ya it sounds like the manure may have been a little hot, ie still composting. This may stop germination or at least slow it down. But you got the right idea, spreading a bit of dirt on top should help. The hay just helps keep the moisture on the soil and seed helping the germination, peat moss also may be used in the same way. Anyway keep the moisture on it and it should germinate.

dead grass

Hi What is the best thing I can start doing for my front yard ,I missed the right time to seed and most of the grass I planted to late last year is all brown and most like ly dead 

Should I rake out dead and lay down new dirt any ideas would be great we are trying to do it with out harsh chemicals

Dave & Jan Connell

11 Little Tree La. Fram Ma.

dead grass

There is no “right” time to seed just times that may be easier. If your around to water and get it to establish you can seed any time. Just don’t throw out seed in the middle of a drought and go away and expect it to germinate or you’re really just feeding the birds.

Sounds like you may have had a bit of snow mold over the winter which is not a big deal I would just re loosen up the soil you had and don’t bother with the new soil unless you want to fix any low spots. Use some organic fert that has some phosphorous in it like Jonathan greens organic fert, be sure to stray away from anything with corn gluten meal and you should be good to go.

Help. I seeded my yard now it's infested

I seeded my back yard and now it seems weeks later it is infested with what I think are Mosquitos. How do I get rid of these. By infested I mean there are thousands.... But only where I have seeded. I don't feel like I can even go outside without getting attacked my dog included. Help. 

bugs on new lawn

Bugs like the mosquitoes and especially the may fly are really attracted to the wet soil and moisture. They should pass as you start to slow down on the watering or as the weather warms. You could do a spray to do a quick knock down if you need there are both organic and synthetic mosquito controls out there that may help.

New lawn

We had a new lawn put down over a septic system in May--it was hydroseeded over a few inches of loam and took well for the most part but there are a number of scattered patches where the grass didnt grow or died off.  I'm trying to determine the best approach to fill in the gaps--the big challenge is that we are only going to be around for a few more weeks to water any new seed we put down.  Would it be better to seed/water now through early September or wait until spring when we can water on a more regular basis?


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