Why is My Grass Different Shades of Green?

When scanning your lawn, you hope to see an even, rolling green color as a sign of the effort put into caring for your grass. Any uneven coloring calls for inspection since it may signify a problem with the grass or soil, although it may be due to a less severe reason, such as mixed grass types or new growth.

You might even notice grass looks greener after cutting it, which is simply a result of exposing the lower parts of grass that weren’t getting as much sun.

What Makes Grass Green?  

Grass Types And Their Shades

All grass is one or another shade of green based on how much chlorophyll it stores in its blades. Chlorophyll is the energy-dense molecule that absorbs UV light to convert carbon dioxide and water into glucose, which the plant uses for nourishment.

The more energy stored from photosynthesis, the longer plants are able to endure stressful conditions. The darkest green grasses are cool-season ones, many of which maintain their green blades over winter and survive on their stored energy. Warm-season grasses benefit from long days with hours of sunlight, so their chlorophyll concentrations are lower than grasses that live during periods of shorter daylight hours. Warm-season types tend to be lighter or medium green in color.

Greenness By Grass Type   

While grass color can be affected by age, health, and environmental factors, cool-season grass species tend to be darker than warm-season ones. The darkest grasses thrive in spring and fall, including Kentucky bluegrass, fescue, and rye. Warm-season grasses include the medium-green Bermuda, zoysia, and buffalo, with very light green grass types being St. Augustine, centipede, and Bahia.

In general, new growth of all grass types is a vibrant shade of light green. The chlorophyll stores in new blades are low while they are actively using energy to extend and mature, and they will darken over time.

Why Is My Grass Light Green And Dark Green?      

Is New Grass Lighter In Color

A multicolored yard or uneven grass color can be due to multiple potential causes. It may be due to a mix of grass types or some kind of stress in isolated areas. The pattern of the coloration and the shades of green will indicate what the reason might be.

  • Spotty light green patches – If you’re seeing light green grass patches in your lawn, in one area, or across the yard, it may be a sign of yellow patch disease; an iron, nitrogen, or other micronutrient deficiency; or a turf Inspect the grass closely to look for weakness, the presence of insects like aphids, or for fungal growth at the ground surface level.
  • Even or semi-even mixture – Grass that is multicolored evenly across the yard is usually due to a mix of grass types growing together. Seed producers often mix grass types, as some grass will compliment each other for dense turf, like Kentucky bluegrass and Fescue or St. Augustine and Centipede. Years of overseeding or invasive grass growth can also result in a lawn with a variety of species. Lawns with different seasonal varieties may see an uneven color mix as new grass grows out of dormancy in transitional periods of the year since new grass is a different color of green.
  • Large sections mismatched – If there are two or more large sections of your yard that are darker or lighter than each other, or the front yard is lighter than the back, it may be due to light-colored grass growing in sunnier areas, where darker, shade-tolerant types are growing in parts of the property that get less sunlight.

How Do You Fix Light Green Grass?

When you have light green grass in your dark green lawn, it stands out, and whether it’s healthy or not, the mixed coloration sends the signal that something is wrong. When it is actually a sign of a problem, diagnosing the cause is the first step towards fixing the discoloration.

  • Yellow patch disease can affect grass in too-moist growing conditions that support fungal growth, which competes for nutrients in the soil and damages the grass roots, resulting in lime green grass that will continue to yellow as the grass declines in health.
  • A nutrient deficiency in the soil may also be the cause of grass that’s lighter green than normal. Nitrogen and iron deficiencies are particularly signaled by a fading of the grass’ color. A soil test will reveal whether it is low or abundant in essential macro and micronutrients.
  • Light green grass might also indicate uneven stress on the lawn. This might happen following uneven fertilization, uneven watering, or too much fertilizer or salt. A moisture and soil test should reveal if you’ve been over or underapplying.
  • Aphids may be the cause of uneven grass color. These sap-sucking insects stress the grass blades, which fade in color as they lose glucose and other essential nutrients in the plant tissue. If you see aphids, or any other pests, in one part of the yard, inspect the rest of the grass to find out how extensive the problem is.
  • A healthy lawn with mixed grass coloring might be able to be evened out with a selective herbicide. This may be an option if the color isn’t too mixed, say for spotty grassy weeds like crabgrass or orchard grass. A well-integrated multicolored lawn might need a more patient and yard-wide approach.

How Do You Keep Your Yard To One Color?

Keeping A Green Lawn

If you have an unevenly colored lawn due to multiple species being present, you have a few options. Overseeding with your desired grass seed during its growing season will, over multiple years, increase the density of the wanted grass and crowd out unwanted species. Choosing grasses with similar colors will provide reinforced density with an even green cover.

However, some species may be difficult to get rid of and may require a more direct intervention. For a faster transition towards an evenly green lawn, you can consider tilling the yard to regrow from seed. It may depend on the size of your yard and other contextual factors whether regrowing from scratch is possible or preferable. Similarly, installing sod with a uniform species will get an even green color on the lawn sooner than later.

How Do You Manage Multiple Grass Types In One Yard?

A difference in the grass types between the front and back yard is easier to manage and adjust to than a patchy or evenly-distributed mixture. For multi-species yards, it’s best to maintain for the dominant species. If they are complimentary, they should both be able to tolerate similar care strategies.