8/22/2025 - By Cort Hall

For lawn care professionals, fall is not the end of the growing season; it is the start of an opportunity. Overseeding is one of the most effective ways to rejuvenate tired turf after a stressful summer, improve density, and outcompete weeds. Whether you are working with cool season grasses in northern climates or maintaining a lush appearance year-round in transitional zones, a well-planned overseeding program can deliver noticeable results that your customers will appreciate.

Beyond the agronomic benefits, overseeding can also boost your bottom line. It is a service that not only improves lawn health but also increases customer satisfaction and loyalty, helping you retain accounts and attract new ones through visible, lasting results. By combining proper seed selection, timing, fertilization, and aftercare, you can set the stage for greener, healthier lawns that stand out long after the competition’s color fades.

Overseeding is Critical in Late Summer/Early Fall

Fall overseeding is important because it gives the turf the time to develop in full before getting to the next harsh summer season. The goal for all your turf stands is to grow roots, and most of that development happens in the fall. Overseeding and the maintenance of developing seeds give you a great opportunity to care for areas that saw the brunt of summer stress and rebuild them, so they are back on track.

How to Choose the Right Seed for Overseeding

When we are choosing seed for our Matric Blend, we look at a variety of factors. First off, we want to make sure that we have a .0% weed and .0% crop blend. I am of the camp that genetics are important in your seed, but if we are also getting weeds that are hard to clean up, the overall quality of turf is going to decrease.

Second, we go to our vendors and ask for varieties that do well in local trials. We look at overall quality, disease resistance, drought and heat tolerance, winter color, etc. We then choose the varieties we want to go with and use that as our standard for blends in the upcoming season. Having a standard that you know will do well for your area is a great tool to build on, so that you know you will be growing on a firm and established foundation.

What to Look for on the Seed Bag When Overseeding

When selecting seed for overseeding, the label on the seed bag is your best guide to quality. Look for a high germination percentage—ideally 85% or higher—to ensure strong, consistent growth. Check the “purity” percentage, which indicates how much of the contents is actually the listed grass species; higher purity means fewer unwanted seeds. The “crop seed” and “weed seed” percentages should be as close to zero as possible, and “noxious weeds” should be listed as none. Pay attention to the seed variety or blend, making sure it matches the turf type and climate in your region. Finally, note the test date—seed loses viability over time, so fresher is always better for optimal results.

Understanding how to read the crop and weed section on the bag is arguably the most important. I would also say that understanding the germination rate and % of each blend in a bag is important to know as well, so make sure to keep those areas in mind.

Overseed Best Practices

In my opinion, the most misunderstood part of seeding is that customers use too much seed, causing problems by overcrowding. Sure, on one hand, it looks good in March/April, but these yards will traditionally have more issues than a yard that got a proper seed rate. Try to hit a 4/5lb rate per 1000 sq ft in an overseeding situation, 8lbs in a renovation situation. More is not always better when it comes to seeding, so make sure you know what the needs of different areas are. As always, if you need help to identify lawn needs, your local Harrell’s rep or I can help you with that.

The Best Fertility Setup for Successful Overseeding

Since plants are producing roots going into fall, I want a chunk of fertility to be down before December if possible. I would like to see about 2-2.5lbs of nitrogen before soil temperatures drop down too low. POLYON® controlled-release fertilizer is a great option for both starter fertilizer and dormant fertilizer, which you can read more about here. I like the POLYON® option because it will stay with the turf all winter and help come out in the spring, due to its release mechanism relying on temperature and not moisture. As the ground warms up, so does the POLYON®.

We have plenty of data suggesting that if you do proper fertility in the fall and proper fertility in the spring, you will have a higher quality of turf and fewer weed issues.

Further Overseed Tips

Understanding the seed and your options is important, but it can also be a rabbit hole that can get confusing very quickly. Trust me when I say there are many different schools of thought on seed, and many are not even things you need to think about when choosing yours. We have a non-negotiable that we are trying to always lead with quality; we have high standards, and we are expecting our seed to be at that standard. Picking out seed does not have to be challenging, which is why you have us. Just call your local Harrell’s rep and ask for the Matrix Blend; they will get you set up and ready for a successful overseed season.