What Causes These 50 Shades of Green Like This? How Do I Fix It?

I recently leveled my Bermuda lawn using sand, compost, and cow manure, then overseeded it with Pennington Rye. After 10 days, I noticed patches of grass with different shades of green. Now, 15 days later, these patches are still there. Am I overwatering?

A soil test showed the pH is 7.8, and phosphorus was low, so I added sulfur and super triple phosphate to fix it. How can I achieve a smooth, carpet-like lawn in Zone 8a, Dallas, TX?

The dark green is probably Bermuda grass growing through. Young grass is usually lighter green at first too

Gale said:
Do you have dogs?

My thoughts exactly. Nitrogen.

Why overseed with rye when there’s Bermuda? My understanding is Bermuda fills in by itself. Is there a plus side to rye instead of overseeding with common or hybrid Bermuda? Or should I just add nitrogen and iron after core aeration and let it run its course?

@Blaine
Many overseed with annual rye as a green cover for winter when Bermuda is dormant. It’s common in golf and certain regions. It might help protect the Bermuda while it’s not growing, but it has downsides. Personally, I’m not a fan of it, but it has its place

Not sure what the original poster’s purpose was. It’s pretty late in Dallas for a top dressing, I think, and hard to tell what’s rye and what’s Bermuda coming back, which probably answers their question.

@Arin
Rye isn’t great. I’d use a non-midnight blend of Kentucky bluegrass, which works well with Bermuda. Ryegrass can chemically kill nearby grass, a concept known as allelopathy. I suggest looking it up if you don’t understand it. It means it kills nearby grass chemically. Ryegrass is unique in this manner, and using it with anything else you care about is not a good idea. I suggest you look up allelopathy.

@Lex
I don’t think you read my comment correctly.

@Blaine
People don’t overseed with Bermuda because it’s almost impossible to kill. I’m not being sarcastic either. It’s an exotic invasive weed.

The hedge and fence line plants are the highlight. Absolutely incredible!

Aerate, as in pencil tine

Maybe differing alkaline levels or perhaps dog pee. With Bermuda, I like to use a 3-4-3 fertilizer once a year at least. Then, you can find a good NPK fertilizer to use every few weeks. Make sure to cut your Bermuda short; that’s how it likes to be

Be careful with iron around concrete and other surfaces as it will stain quickly. That said, your lawn will love it :+1:

One option might be that the soil is more compacted in some areas, so the roots aren’t as deep. I mention this since aerating the soil isn’t a hard task, and it’s worth doing before trying other more complicated solutions that might cause more harm than good

It might be uneven fertilization

I don’t know but love your hedges and plants in the back. Great lawn overall

I’d try some Ironite

Shannon said:
I’d try some Ironite

I agree. Although Ironite has gotten so expensive around here. I’ve been using Fertilome chelated liquid iron or sometimes Southern Ag chelated liquid iron (whichever is less expensive) through a hose end jar. You need to be careful when spraying it because it will stain concrete, stucco, etc. I apply it right after the lawn has been cut.

Soil test showed pH of 7.8

pH isn’t as important as many think, but that is kind of high. What percentage of organic matter and/or CEC value did the test show? If it was low, consider some compost.

Micah said:

Soil test showed pH of 7.8

pH isn’t as important as many think, but that is kind of high. What percentage of organic matter and/or CEC value did the test show? If it was low, consider some compost.

pH isn’t as important as many think

It actually is important. You can spend a lot of money on a poor lawn, but if the pH is off, you’re just wasting it. The grass won’t absorb what it needs

pH issues aren’t as common as people think; many just throw lime down without testing.

@Toni
At least as important as pH is the soil’s buffering capacity (CEC). If your soil has little to none, the pH reading is not very significant. A bit of rain, and it will seem acidic, and the next day the pH could be 2 points higher. Trying to ‘fix’ that is a fool’s errand if the main issue is insufficient organic matter (which helps buffer pH). If you have plenty of compost and organic matter in your soil, and a high CEC, you simply won’t have pH problems in almost all cases.