How Late Can I Overseed Grass This Fall?
Today I received four questions via Twitter about overseeding in the fall.
Remember, Overseeding is just like tucking your kids to bed!
Here is my take on overseeding grass this fall. (13:17)
The discussion on twitter.
@teamccloud (Elizabethtown, PA) D WiseGrass: Couple questions abt the grass seed. Do I just scatter it in that thin area? Or do I need to do anything else first?
- D teamccloud: The seed just needs contact with the soil. So… since it is raining today you can just sprinkle it on top and it will work.
- D WiseGrass: Thanks! I figured I’d have to go out in the rain.
@jeremywalter (Lancaster, PA) @WiseGrass Dumb idea to do “overseeding” this time of year for a very thin yard?
- @jeremywalter Seed germination depends on the soil temperature and continued growth depends on the nutrients available from the soil.
- @jeremywalter Soil temperatures are still around 65 to 70 so grass will germinate fine in the next 2 weeks. I would seed today yet.
- @jeremywalter The key is to get the seed to touch the soil. Either by lots of rain, aeration, or rake to expose some soil for the seed
- @jeremywalter The bigger question in October is, “Will the infant seedlings survive a cold winter?” You never know ‘till next spring.
- @jeremywalter It’s a game of numbers. A percentage of seeds will survive. That percentage goes down as winter sets in. So seed heavier.
- @jeremywalter OR. Wait to throw seed ‘till there is little or no chance for the seeds to germinate this fall. A dormant seeding.
- @WiseGrass So if when I get home it’s still raining, ideally throw down some seed and rake over it?
- @jeremywalter If it’s still raining, you probably don’t even have to rake it. The seed will slither right down to the soil.
- @jeremywalter I would seed today. AND throw some more down after Thanksgiving. The dormant seed will have all winter to work its way down.
- @WiseGrass You’ve just increased my knowledge of grass and seeds 10 fold. Thank you, my Seed Czar.
@gardenofwords (Wilmington, NC) @WiseGrass My question: when can you mow if you have overseeded?
- @gardenofwords Great question! You can mow as soon as the seed is stuck to the soil. Like after a rain or several heavy dews.
@jurina (Lancaster, PA) @WiseGrass just a quick one: is it too late to overseed? When IS it too late?
- @jurina Too late to seed after November 4th. Election day. After that it is too late to cast your seed to impact your turfgrass community.
Video Notes:
- Green Cast online soil temperature map
- You can find PL Rohrer’s (Rohrer Seeds) in Smoketown.
Any more questions? Click “view comments” and add your question.
Posted by Paul Stoltzfus on 10/16 at 10:18 AM in Lawn Care
I was also planning to put down a winterizer/fertilizer this fall. If I put seed down today, how long do I wait until I put down the winterizer?
By Rioux on 2009 10 17
Paul, what an interesting video. Wasn’t prepared to watch the whole thing, but I got drawn in because you really know your stuff and have a good way of communicating it. After 17 years at this house I finally took an interest in my lawn last year and rented a slice overseeder and did the front and back lawns. Holy smokes, the lawn looked better than it has in years. Your video today convinces me to overseed again, though this time perhaps without the slicer. Question: My lawn is lumpy and has low spots and holes. How to fill them? Some suggest sprinkling some soil a little at a time, but I’m not that patient. Just pile on the topsoil and reseed? If I do that, do I have to dig up the old grass first? I’m talking about a depression maybe two or three inches deep and a foot or two in diameter.
Thanks and keep up the good work. I’ll send you my address via email.
By Ken Stadden on 2009 10 17
RE: Rioux (you get a free 3lb bag of seed: CONGRATS! please e-mail and we will ship your seed on Monday)
#1 The new seed will really benefit from a good starter fertilizer right away like 10-20-10 Anything with a high middle number will have lots of phosphorus which is what the seedlings need to push roots.
#2 The winterizer can wait ‘till Thanksgiving when there should be little top growth and more of the nitrogen will sucked into the roots and stored as carbohydrates.
CAUTION: Thanksgiving is only 5 weeks away so only put about 1/2 to 3/4 of the recommended starter fertilizer on now so that you can safely apply the full winterizer dosage and optimize your plants for the spring green up. TOO MUCH FERTILIZER in the fall can lead to pink snow mold in the spring.
By Paul Stoltzfus on 2009 10 17
RE: Ken Stadden (You get a free 3lb bag of seed #2: CONGRATS! Thanks for e-mailing your info to me already. We will ship your seed on Monday)
And we follow each other on twitter. How cool is that!
#1 The slice seeder is the way to go, you get much better seed to soil contact and there is a better chance to keep the seed moist during germination.
#2 Shallow low spots are tough to work with since the existing grass tends to slightly lift the soil and burn out the new seedlings. I always notice that when filling a depression the perimeter does not grow well for a few seasons. My theory is that the edges of the bowl shaped depression are drying out because of the slight void created by the decaying grass. The deeper part of the depression is no problem since there is plenty of virgin soil to establish into before it “jumps the gap”. Jumping the gap for a tiny seedlings is almost impossible to do. Soooooo… before you fill in the depression take a weed eater and cut the grass down to the soil, then the gap will be very little to nil. Yes, it would help to dig up the grass first but in the fall you should be fine with cutting the grass very very short in those depressions - much less mess too!
#3 Let me know how it works out for you
By Paul Stoltzfus on 2009 10 17
good video, just reseeded a few patches where I had a garden so I figure the soil is pretty good.
Remember Remember the 4th of November
By @ethanD on 2009 10 19