.png)
When and How to Scalp and Overseed for the Perfect Arizona Winter Lawn
- Oasis Green
- Aug 22
- 9 min read
Expert Advice from 30+ Years Installing Phoenix Lawns
If you're reading this article and it's mid-September, there's something important you need to know: it's probably time to turn off your water now. That's right — if you have Bermuda grass and you're planning to overseed this fall, you should be shutting off your irrigation system within the next week or two. Your summer grass needs 3-4 weeks to dry out before it can be properly scalped for overseeding in early October.
I know it feels counterintuitive. After babying your lawn all summer through 115° days, the idea of deliberately starving it of water seems harsh. But trust me — I've been in this business long enough to know one thing for sure: Arizona lawns don't behave like lawns in the rest of the country. This deliberate dry-out period is the most proven process for successful overseeding.
Clients moving here from back east are usually surprised when I tell them their grass is going to go brown in the winter if they don't overseed. That's the tradeoff of living in the desert — beautiful sunshine almost year-round, but Arizona's Bermuda grass just can't handle the cooler temps.
Overseeding is the trick we use to keep a lush green yard through the fall and winter. Done right, you'll have a thick carpet of gorgeous ryegrass to carry you until spring. Done wrong — well, you'll be staring at patchy bare spots and wasting a whole lot of water. I've made mistakes myself back in the early days, so trust me when I say timing and technique absolutely matter.
Understanding the Arizona Grass Cycle
Before we dive into the how-to, let's talk about why overseeding works. Bermuda grass thrives in our scorching summers but goes completely dormant when nighttime temperatures consistently drop below 70°F. Ryegrass, on the other hand, loves our mild Arizona winters. The beauty of this system is that you get the best of both worlds:
Summer: Heat-tolerant Bermuda handles triple-digit temperatures
Winter: Cool-season ryegrass provides lush green coverage
Transition: Each grass naturally takes over as conditions favor it
The key to making this work is understanding that you're essentially hiding your dormant Bermuda lawn in the winter, knowing that that it will come back strong in the spring. That's why the prep work — especially that dry-out period we're entering right now — is so crucial.
The Best Time to Overseed for Your Winter Lawn in the Phoenix Metro
If you only take one thing away from this article, it's this: the first two weeks of October are gold for laying down your seed. The ryegrass seeds need a couple days of a hundred degree temperatures to help them germinate but, the newly sprouted grass need the cooler temperatures so they don't burn up.
In the beginning of October the temps are just right to accomplish both these goals.
Too early (September): Triple-digit afternoons cook the seed if it sprouts too early, before it has time to get established
Too late (November): Cold soil prevents proper germination of the seed
Sweet spot (Early October): Soil temperatures between 60-75°F for optimal growth
I can't tell you how many times I've gotten calls from frustrated homeowners who got busy or weren't paying attention and forgot to turn their water off. While starting the dry out period late isn't a total deal breaker, it will make the process of overseeding a lot more difficult.
Step-by-Step: How I Recommend Overseeding
As I mentioned, timing is critical when it comes to overseeding your lawn and if you wait too long to start the process, you may miss the opportunity altogether. That's because in order to overseed with winter grass, there is some prep work that needs to happen first.
1. Turn the water off in September
First you need to start drying out your summer grass about 3-4 weeks before you plan to start overseeding. You need to turn the water off completely so your lawn has time to get nice and dry (but don't turn the water off to the rest of the yard if you can help it).
2. Scalp the Bermuda
When the grass is nice and dry, lower your mower to the lowest possible setting and bag all those clippings. I always say, don't be shy — it feels like you're scalping it bald, but you've got to open up the canopy so the rye seed can actually hit the soil.
3. Power rake if needed
In older well established lawns, a power rake can help thin out the thatch. Without it, your seed just sits on top of a sponge of dead grass.
4. Seed selection
Perennial ryegrass is the go-to here. It's quick to germinate and holds up well in our winter sun. Annual rye might look good at first, but it dies off early and leaves you with a mess come spring.
5. Seed application
Spread at least 8–10 pounds per 1,000 sq. ft. evenly across the lawn. ( I like a super lush lawn, so I always go heavy). Its best to use a broadcast spreader for uniform coverage. However, you may want to toss the seed by hand along the lawn edges or use a drop spreader to minimize overspray outside the lawn area.
6. Watering schedule
Here's where homeowners usually trip up. You've got to water light and frequent for the first couple weeks or until a day or two before your first mowing. This works out to 3–5 times a day if possible — just enough to keep the soil damp. After your first mow you can cut it back to 3-4 times per week with a slightly deeper watering schedule.
Fertilizing
After your first cut, you will want to do a light application of turf builder fertilizer to promote healthy growth and ensure that your lawn remains lush and vibrant. Applying this regularly throughout the growing season can also help keep your lawn thicker and healthier.
8. Mowing and maintenance
Your first mow comes when the rye is 2–3 inches tall and the goal will be to keep your lawn cut it to about 1 1/2 inches throughout the season. And don't forget to keep that mower blade sharp— nothing ruins a new lawn faster than tearing it with a dull blade. A typical cut cycle will be once a week.
Common Mistakes That Kill Overseeding Projects
Over the years, I've seen the same mistakes repeated over and over. Here are the big ones to avoid:
Not drying out the Bermuda enough: Moist grass will make it harder to scalp and prep so do yourself a favor and give your Bermuda grass enough time to get nice and dry
Wrong watering during germination: Too much water causes fungus problems; too little and the seed dies so make sure you are keeping a close eye on this
Using cheap seed: Poor germination rates mean you'll end up reseeding anyway
Skipping soil preparation: Trying to apply seed to thick or thatchy ground can leave you with a patchy winter lawn
Rushing the first mow: Mowing too early rips seedlings out by the roots
Caring for Your Ryegrass Lawn
Planting the seed is just the first step. The real test comes with how you care for that new winter lawn while it's getting established. Over the years, I've found these practices make or break a ryegrass yard in Phoenix:
Keep it consistently damp
Rye seed is fragile during germination. If the soil dries out for even a few hours in those first days, you'll lose patches. That's why I tell clients to water lightly several times a day in week one. See the watering section above for best watering practices.
Don't rush the first mow
It's tempting to tidy things up when you see that lush green fuzz coming in, but wait until it hits about 2–3 inches. Mow too early and you risk ripping seedlings out by the roots.
Birds love rye seed
If you've overseeded in Arizona, you know the struggle. Doves, sparrows, even pigeons treat it like an all-you-can-eat buffet. To minimize the buffet effect, I recommend running the sprinklers immediately after seeding so the seed sticks to the soil. Some folks lay down a thin mulch layer or use bird netting for smaller areas. Personally, bird feasting is another reason why I lean towards laying a heavier amount of seed in the beginning.
Mowing and fertilizing tips
Mowing height: Keep ryegrass at 1.5 inches (taller than your summer Bermuda)
Blade sharpness: Sharp blades are critical — dull blades tear new grass
Fertilizing timeline: Wait for healthy seed germination, then use starter fertilizer (16-20-0)
Winter boost: Mid-winter high-nitrogen feed maintains that dark green color
Mind the foot traffic
Rye may look hearty, but in those first couple weeks it's delicate. Dogs, kids, or even the Amazon guy cutting across your lawn can crush sprouts. If you can, rope it off or at least keep heavy activity away until it's well established.
Why Timing Is Everything (A Hard Lesson Learned)
I can't stress this enough: overseeding success lives or dies on timing. That's why we lock in on early October in the Phoenix metro. Miss that window and you're either fighting the heat or the cold, and both will cost you.
One story that still sticks with me came from a homeowner in Gilbert who wanted a lush green backyard for his daughter's outdoor wedding. He insisted on overseeding late October, even though I warned him we were pushing it. Sadly, but not unexpected, the seed didn't establish in time. By the big day the lawn was soft but muddy, and the high heels of the wedding guests tore it up in hours. Instead of a green carpet, they got mud-caked shoes and a ruined yard. It broke my heart to see, but it shows why timing is non-negotiable.
Cost Considerations
Let's talk dollars and cents for scalping and overseeding a typical 1500-2,000 square foot lawn in the Phoenix metro:
Scalping and Overseeding Your Own Lawn
Low end: ~$100–$150 (minimal seed, hand raking, minimal materials)
Mid range: ~$200–$400 (better seed volume, minor prep, topdressing, fertilizer)
High DIY: ~$400–$700 (more seed, tool rentals, compost/topdress, fertilizer)
Hiring a Landscape Maintenance Company
Typical landscaper: ~$200–$400 (basic overseeding package)
More thorough package: ~$350–$600 (prep work, scalping/dethatch, cleanup)
Premium/full-prep: ~$600–$800 or more (scalping, debris removal, aeration, topdressing, follow-up care)
In addition to the costs of scalping and overseeding, don't forget to take into account the water costs to keep your grass green throughout the winter, and any additional fertilizer applications or maintenance services.
FAQs: Overseeding in Arizona
1. Can I use tall fescue instead of ryegrass in the winter? Tall fescue will grow here, but it's not ideal for winter overseeding. It germinates slower than rye and doesn't give you that uniform green carpet. Stick with perennial ryegrass for best results.
2. What if I don't overseed at all? Nothing wrong with that — a lot of folks choose to let their Bermuda go dormant and save water. Just expect a golden-brown yard from November through March.
3. Do I really need to scalp the Bermuda? Yes, you do. Skipping this step means the seed won't hit soil, and you'll get thin or patchy coverage. Scalping is messy, but it's the foundation of a good winter lawn.
4. What's the right mowing height for ryegrass? For homes in the Phoenix metro, I recommend to keep it around 1.5 inches. Taller grass helps shade the soil and gives you that soft, thick lawn people love.
5. How long will my winter rye last? Typically from late October until April, depending on weather. As temps warm back into the 90s, the rye fades and Bermuda naturally takes over again.
6. Can I overseed if I have an older sprinkler system? Absolutely, but you might need to hand-water problem spots during the critical germination period if coverage isn't uniform.
7. What about shady areas under trees? Ryegrass handles light shade better than Bermuda, so these areas often look great in winter. You might need slightly higher seeding rates in shaded areas for best results.
Overseeding Means a True Winter Showpiece
Overseeding can feel like a chore, but when done right, it transforms your yard into a true winter showpiece. The key is starting the process now — turning off that water and letting your Bermuda grass begin its dormancy period so you're ready for scalping and seeding in early October.
Remember, this isn't just about aesthetics. A healthy winter lawn provides a stable surface for kids to play on, gives you outdoor entertaining space all season long, and keeps your property looking its best year-round. It also keeps the wife happy when she wants to take the annual Halloween or Thanksgiving pictures of the kids on the front lawn (don't ask me how I know!)
Or Skip the Hassle Altogether
If you are reading this article because you love the look of a lush green winter lawn but find yourself overwhelmed by the annual overseeding requirements here in Arizona, I will tell you that there is another option.
You can still have that perfect green lawn without the timing, water restrictions, and maintenance headaches and we'd love to help you explore your options. Contact us today for a free consultation to discuss artificial turf or other low-maintenance landscaping solutions that work beautifully in Arizona's climate.