Best Sod for Shade in DFW: What Works Under Trees

Shade is a light problem, not a grass problem. Every warm-season lawn slows down as light drops, but each one gives up at a different point. Measure your light first, then match the grass.

How much sun does sod need in North Texas?

Regional guidance is blunt. The North Texas Water Is Awesome guide says Bermuda, Zoysia, St. Augustine and buffalograss “do poorly in areas that receive less than 5 hours of sunlight a day.” The LSU AgCenter says most turfgrasses need four to six hours of full sunlight, or longer for partially shaded areas, and Mississippi State Extension puts St. Augustine at about 4 hours of direct sun or a full day of high-quality filtered light. Plan on 4 to 6 hours as the floor.

To measure, watch the yard at about 9 a.m., noon and 3 p.m. in late spring, once the trees have leafed out, and count the hours of direct sun. Remember that shade changes: the LSU AgCenter notes that pruning a tree can stimulate its growth and lead to denser shade over time.

How does Texas A&M measure shade tolerance?

Hours of direct sun are hard to compare from one yard to another, so Texas A&M researchers measured the light itself: the total a plot receives in a day, in moles of light per square meter. In a two-season field trial at College Station, they put zoysia, Bermuda and St. Augustine plots under shade cloth that cut light by 30 to 90 percent and recorded the lowest daily light at which each grass still kept acceptable quality. For scale, full summer sun measured about 46 to 48 in that trial. The minimums were noticeably lower in spring and fall, so summer light is the number to measure.

Which sod is best for shade: St. Augustine, Zoysia or Bermuda?

Not every St. Augustine is equal, either. A&M notes that the variety Floratam has poorer shade tolerance than the others it lists, which include Palmetto, the one we sell and the one A&M used as its shade-tolerant check. Ask which variety you are buying.

What should you do about grass under trees?

• Mow higher. Mississippi State says simply raising the cutting height enhances shade tolerance, and the LSU AgCenter says to mow shaded grass slightly higher than grass in sun. A&M’s St. Augustine guide says 2.5 to 3 inches, and 3 to 3.5 inches in shady lawns, so use the taller range under trees.
• Keep traffic off. Foot and pet traffic stress shaded turf, and Mississippi State calls riding-mower wheels under trees a main cause of decline. String-trim the tight spots or mulch under the drip line.
• Water deeply and less often. Shade lowers water needs, but tree roots compete for moisture. Wilting turf means it needs water (Mississippi State), and the LSU AgCenter advises deep, infrequent irrigation.
• Do not over-fertilize. Mississippi State says to use the normally recommended nitrogen rate and no more, because excess can hurt shade tolerance.
• Protect the roots when you prepare the ground. Texas A&M says not to add soil over tree roots without a professional horticulturist’s advice, so do not regrade or pile topsoil around a trunk.
• Prune for light with an arborist. Pruning can let in more light, but as noted above it can also lead to denser shade later.

When should you skip grass under a tree?

The LSU AgCenter offers a simple test: if very few plants, even weeds, grow in the area, there is not enough light. In full or dense shade, the Water Is Awesome guide says shade-tolerant groundcovers, shrubs, perennials and ferns make better plantings than turf, and a pervious patio of pavers, natural stone or gravel works too; both avoid muddy, bare soil. The LSU AgCenter names liriope, Asiatic jasmine and holly fern, and says mulch works if bare ground is not acceptable.

What if the yard is half sun and half shade?

Many yards are. Two grasses in one yard is workable, but each wants its own mowing height (A&M lists 2.5 to 3 inches for St. Augustine and 1 to 2 for fine-textured zoysia), so plan where one ends and the next begins. Text us photos of the lawn in the morning, at noon and mid-afternoon, and tell us where the trees are. We will say which variety fits each part and whether a section should skip sod. For the variety choice, see Bermuda vs St. Augustine vs Zoysia and Zeon vs Palisade Zoysia.