Kentucky Bluegrass Vs. a Tall Fescue

Growth Habit

• Kentucky bluegrass plants develop spreading underground rhizomes that create dense, thick tufts of dark green leaf blades in a lawn setting. The leaf blades are slightly narrower compared to those of tall fescue. Kentucky bluegrass grown from seed establishes a thick lawn less quickly than tall fescue. Tall fescue plants develop a bunching habit with numerous stems and blades emanating from a central tuft. It doesn't spread out as much and therefore thin areas or holes may develop in a lawn and require occasional reseeding.

Maintenance

• Tall fescue lawns are comparatively lower maintenance than those comprising Kentucky bluegrass. Tall fescue will better tolerate warmer summer temperatures, moderately dry soil, more foot traffic and infrequent mowing compared to bluegrass. While bluegrass is quick to sprout back from any traffic wear, summer heat or dry soils causes plants to become semi-dormant and turn yellow or thatch brown. Much more irrigation and proper mowing frequency is needed to keep a Kentucky bluegrass lawn looking perfect, especially during the summer.

Regional Considerations

• In higher elevations and parts of the northern United States and southern Canada, Kentucky bluegrass is better suited. Bluegrass will hold its green color longer into fall as temperatures more frequently drop below freezing. Tall fescue is better at lower elevations and in the slightly warmer parts of the northern and central United States. Wherever grown, both bluegrass and fescue needs to be mowed high, around 3 to 4 inches tall to maintain the densest, greenest lawn carpet and to avoid invasion by weeds.

Annual Upkeep

• Kentucky bluegrass lawns need a bit more fertilization, particularly a supply of nitrogen, as compared to tall fescue. Since summer temperatures and rainfall regimes in the United States often fluctuate year-to-year, Kentucky bluegrass lawns are more likely to suffer yellowing and partial dormancy as heat waves or seasonal droughts set in. Both grasses need sunshine to grow their best and create a thick carpet. Too much shade creates thin spots for weeds to sprout. Since Kentucky bluegrass is so sensitive to heat and drought, most seed mixes contain a blend of other fescues to offset excessive browning in summertime. Tall fescue seed typically contains 100 percent tall fescue.