Clay soil is heavy and often difficult to work with. It has a high water retention rate, making it difficult for plants to thrive during cool and hot seasons. So, what grass grows well in clay soil?
The best grass seed that grows well in clay soil includes buffalograss, zoysia, tall fescue, bermuda grass, and perennial ryegrass. These grasses have deep and extensive root systems that help them tolerate poor drainage, low air circulation, and hot, dry conditions in lawns with clay soil.
Alternatively, you can improve the clay soil in your yard to make it more viable for other types of grass that prefer well-draining sandy soils, such as St. Augustine grass.
Best Grasses for Clay Soil
When the grass in your lawn isn’t growing thick and full, the problem can be anything from poor nutrition to establishing the lawn on the wrong type of soil. Slow growth, grass turning yellow, and puddles of water in the yard could point to clay soil.
Here are grasses that grow well in clay soil:
1. Bermuda grass
Bermuda grass is a great choice of grass to grow in clay soils because of its fibrous root system that is made up of deep rhizomes. This makes it well adapted for drawing water and scarce oxygen between the fine particles of clay soil.
|Grass type||Warm season grass|
|Soil pH||5.8 to 7|
|Root system + depth||6 inches|
|Water requirements||1 to 1.5 inches of water per week|
The roots of Bermuda grass are diverse and grow at a depth of at least 6 inches. When temperatures start to drop at the onset of winter, Bermuda grass goes into dormancy and later revives in the spring. As such, this grass type can tolerate and survive in clay soil more than most other warm-season turfgrasses.
You can establish this grass from seed – which germinates easily within 7-14 days. Provide your lawn with 1 to 1.5 inches of water weekly to make Bermuda grass grow thicker and able to resist drought, pests, and weeds with ease.
2. Perennial Ryegrass
Perennial ryegrass grows well in clay soils because of its well-developed fibrous root system. The roots are evenly distributed in the soil, growing to a depth of about 30 inches (76cm). As such, the roots of perennial ryegrass are well adapted to drawing moisture and limited oxygen in clay soils.
Being a warm-season grass, perennial ryegrass is very hardy and can tolerate tough growing conditions even with minimal watering and care. One of its benefits is that it provides shade for most cool-season grass-seed varieties, especially after overseeding. This is why you will find it in most mixed bags of grass seed.
Here are the growing requirements of perennial ryegrass in regions with clay soil
|Grass type||Warm-season grass|
|Root system + depth||Fibrous root system; 30 inches deep|
|Soil pH||5.5 to 7.5|
|Water requirements||– Spring: 1.5 inches of water per week. – Summer: 6 to 12 inches of water, 2-3 times per week.|
Pro tip: Perennial ryegrass grows well in a wide range of soils. For example, it is well suited for the acidic clay soils of Georgia due to its soil pH range of 5.5 to 7.5.
3. Buffalograss (Buchloe Dachtyloides)
|Grass type||Warm-season grass|
|Soil pH||6.0 and 7.5|
|Root system + depth||67cm|
Buffalograss (Bouteloua dactyloides) is a perennial grass that grows and thrives well in clay soil. The roots can go up to 12 inches deep, making Buffalograss ideal for areas with clay soil and low rainfall.
Several studies by Riordan and Browning (2003) found that “the root system of buffalograss grew as deep as 60-120 cm long, with some roots excavated at depths of up to 3 meters.” (Source)
Roots of buffallograss are typically less than 1 mm in diameter but grow extensively to occupy soil. As such, this type of turfgrass is known to withstand a certain level of compaction that’s common with clay soil.
Once a buffalograss lawn is established, it can do with minimal irrigation. However, watering may be necessary during the summer months if there is a prolonged drought. 1-2 inches of water every two-four weeks is enough to maintain this type of grass growing in clay soil during the hot months of the season.
Buffalograss does not require as much mowing or fertilizing as other types of turfgrass that grow in clay soil, but it’s still important to maintain the lawn with these practices on an ongoing basis.
Zoysia is a warm-season turfgrass that grows well in clay soil. Its roots grow into a dense, thick system about 2 inches deep in the soil. This makes them well-adapted to absorbing water, nutrients, and oxygen in the top layers of clay soil.
|Root system + depth||Fibrous; 2-inches deep|
|Soil pH||5.8 and 7.0|
|Water requirements||1 inch of water per week.|
Another benefit of establishing a zoysia lawn in the southern states where the soil is red and heavy is that the grass seed germinates and grows into heat and drought-resistant turf. It is also a good grass for winter lawns, being recommended as a plant for USDA hardiness zones 6-9.
5. Tall Fescue
A perfectly healthy lawn can be established on heavy clay soils using tall fescue grass seed, but you’ll require to irrigate a little more during periods of summer drought.
|Grass type||Cool season grass|
|Soil pH||5.8 to 6.5|
|Root system + depth||Fibrous; 2-3 feet deep|
|Water requirements||1 to 1¼ inches per week|
Tall fescue is a cool-season grass that thrives well in clay soil due to its deep root systems. It needs little water, making it ideal for clay-heavy areas like the south or east coast of the United States where water is limited – like Texas.
Tall fescue will grow well with just 1 to 1¼ inches of water per week. This is enough to keep the soil moist at a depth of about 4-6 inches.
The main reason why tall fescue is good for clay soil is that its root system is naturally extensive – reaching 2-3 feet deep. As such, the grass can tolerate drought and poor aeration in clay soils more than many other turfgrasses.
6. Kentucky Bluegrass
Kentucky Bluegrass (KBG) is also a great option if you have clay-loam soil in your yard. It establishes easily from grass seed, but it might not be the best grass for heavy clay soil, especially if compaction is a common problem in your yard.
|Grass type||Cool season grass|
|Soil pH||5.8 to 7.0|
|Root system + depth||Fibrous with rhizomes; 2-6 inches deep|
|Water requirements||1 inch of water per week|
The roots of Kentucky bluegrass grow as deep as 2-6 inches, which is quite common for many cool-season grass varieties. Its roots are fairly fibrous, although the grass spreads by rhizomes and tillers to form a dense sod.
KBG requires 1 inch of water weekly. However, Kentucky bluegrass is more drought-tolerant than other types of grass for clay soil, such as tall fescue.
This grass type can tolerate drought better than other types, so while it may seem alright if there are no signs of wilting (due to lack of water) after three weeks without any rain, the grass will go into dormancy, but that does not mean it is dead. It will soon revive and grow back into a green lawn as soon as it rains again.
See Also; Grass varieties that grow in sand?
Characteristics of Clay Soil
Although clay soil is mostly fertile and nutritious, it holds a lot of water easily while lacking air circulation at the same time. Grassroots can easily get suffocated in clay soil, especially when compacted.
The result is slow growth, yellowing grass blades, puddling of water in low areas due to poor drainage in the yard, and a thin, patchy lawn due to shallow roots.
Here are the characteristics of clay soil:
- Small particle size – less than 2 microns.
- High water retention rate.
- Dries out slowly.
- Forms a hard crust that can make it hard for water to penetrate.
- Low air circulation.
- Rich in potash but deficient in phosphates.
Most turfgrasses will suffocate when grown in clay soil. I’d recommend adding organic material to clayey yards – such as compost – to help break down some of the clay bonds between particles. Amending clay soil this way will lead to better aeration and water drainage over time.
You can amend clay soil to make it suitable for different types of turfgrasses, but that might be quite a bit of work. Instead of fixing clay soil to improve its drainage, you can choose to simply plant a grass type that can thrive well in clay soil.
Tips for Growing Grass in Clay Soil
To successfully establish a lawn in clay soil, you need to improve clay soil by adding organic matter, such as compost or well-rotted manure. Avoid adding sand, as it can worsen the compaction of clay soil in your yard.
Here are more tips for growing crass in clay soil.
Aerate clay soil more often
Aeration is key if you’re establishing a lawn on clay soil. It helps air pockets to form in the ground and releases oxygen into the roots. It also makes water and other nutrients more readily available to the grass.
I’d recommend core-aerating and dethatching your lawn 1-2 times every year before winter arrives to maintain a healthy root system within the clay soil column.
Water your lawn less frequently
Clay soil tends to retain water more than sandy soil, or other types of soil for that matter. Therefore, use a different approach to help your grass grow well in heavy soils.
Here are watering tips for growing grass in clay soil:
- Lightly water grass seed to prevent creating a muddy puddle when planting or establishing your lawn.
- Check the soil moisture content up to 6 inches deep frequently using a probe.
- Water your lawn only when the soil is dry at a depth of at least 6 inches.
- Water at a much slower rate than you would a sandy-soil lawn. Water penetrates clay soil at a slow rate, so, it is easy for it to run off the surface and form wet areas in your yard if done at a faster rate.
Note: If there’s any water standing in your yard after watering a lawn in clay soil, allow it to soak into the soil before continuing with the watering schedule.
Do soil tests
Although the list of grasses for clay soil above is helpful, you may want to do soil tests to determine the required nutrients present for the type of grass you’ve chosen.
Here are soil tests that are important before establishing a lawn on clay soil:
- Soil pH test
- Nutrient level (NPK)
- Soil texture
But why is soil texture important? This one is to be sure you have clay soil in your yard. The clay soil may need to be amended first before planting grass seed.
Growing Grass in the Georgia Red Clay Soil
Georgia has a type of clay soil that’s commonly classified as ultisol. The soil gets its characteristic red color from the iron oxide content. Rainfall and waterlogging leach calcium deep down into the soil, leaving it very acidic.
A few types of grass grow well in the red clay soil of Georgia, including Bermuda grass or zoysia grass. Other grass types commonly grown in this state are centipedegrass and tall fescue.
If you want your lawns to grow better, consider top dressing lawn or adding some organic material such as compost or manure so that there will be more air pockets between these hard mineral particles – which will provide easier access to oxygen and moisture needed for growth.
Other ways include tilling deeply before planting, watering regularly, using mulch, or planting drought-tolerant ground-cover plants.
If weeds have overtaken your landscape due to an abundance of moisture, you’ll need to pull them up by hand or use a weed puller, or use a broadleaf herbicide.
Here is a video guide for the best way of growing grass in red clay soil:
References + Resources
- UNIVERSITY OF MARYLAND: Perennial ryegrass
- Lynn Kime, Senior Extension Associate, Pennstate University: Soil Quality Information
H.J.S. Finch, G.P.F. Lane, Science Direct: Clay Soils – An Overview