So that is my first clue as to the reseed window – it comes from my experience.
Reading The Label – Speed Zone – Red Label
It’s probably hard for you to tell, but this lawn here is in Munster, IN and this is 99% crabgrass.
First off, you do NOT have to kill all the weeds. The winter is going to kill them for you and having a few here and there will not get in your way too badly. However, if you have had a big emergence of crabgrass in your lawn (where it is all you can see), you will want to try and knock that back some – mainly so it doesn’t go to seed on you.
Use the down arrows in that window to “scroll” through all the instances where that word appears. As I did this, I found the following very quickly.
Here’s the trick to reading labels fast. Find the PDF online. Make sure it is the VERY SAME product you have in hand. DoMyOwn is a great resource for this .
First one is quinclorac . This is the first choice active ingredient that kills crabgrass that you may be seeing. If your lawn is covered in crabgrass like a carpet – especially through the middle or meaty part of the lawn, you will want to kill it off or at least stunt it really well before seeding.
• Check for snow mold damage. Use a lawn fungicide if necessary.
Overseeding – Bagged grass seeds usually list on the label an overseeding rate that tells you how many pounds of seed you should use per square footage of area. If no overseeding rate is given, apply at half of the regular seeding rate. You should use a blend that matches the growing conditions in your yard and is compatible with the existing turf. Use a slice seeder for best results.
Fertilizer – Fertilizers are described by three numbers that indicate how much of the 3 macronutrients they contain: nitrogen (N) – phosphorous (P) – potash (K). Depending on their chemisty, these elements can be highly soluble for quick release or slowly soluble for slow-release. Some basic types of fertilizer: green-up (typically a high nitrogen product from a quick release source with no added controls), maintenance (typically a well balanced product with no added controls), slow-release (requires microorganisms in the soil to break it down and make nutrients available to plants), organic (e.g., typically slow release granular, milorganite, chickity doo doo), synthetic organics (with a slow-release nitrogen component), step programs (typically green-up, maintenance and winterizer fertilizers that also include weed or insect controls).
Aeration – perforates compacted soil, aids root growth, allows water and nutrients to penetrate better, increases gas exchange. Core aerators remove plugs of soil that can be left to dry on the lawn surface and then raked into the turf. Tine aerators force tines into the ground to create holes but in so doing further compact the soil around the holes. Because of this compaction, we recommend you use a core aerator.
• Watch for pythium blight on ryegrasses when high overnight temperatures combine with high humidity.
5) Water – the seed must be kept wet until it germinates and starts to sprout (about 5-7 days), so start an hour after you’ve seeded and frequently, even multiple times a day if it’s hot to ensure it doesn’t dry out. After a week, reduce watering to twice a day, until the lawn is more established. Watch, though, that you don’t water so heavily immediately after seeding that the water runs off, taking the seed with it.
2) Rake up the area a bit to break down any thatch
In order to combat bald or brown patches, or thicken up your existing grass, over-seeding is a must. Look for a seed that has a combination of fine fescue (light green & tolerates shade), Kentucky bluegrass (makes your grass lush and dark green), and perennial ryegrass (hearty against disease and sprouts quickly).