Late summer and early fall (August 20 through October 15) is the ideal time in Maryland for the establishment of cool season grasses such as turf-type tall fescue, fine fescue, and Kentucky bluegrass. If you cannot irrigate or if water restrictions are in effect, seeding between September 15 and October 15 may be preferable to take advantage of color temperatures and greater likelihood of rainfall. Seeding later than October 15 presents problems with the winter survival of turfgrass seedlings and with competition from winter annual broadleaf weeds.
Seeding in the spring can present problems with competition from summer annual grass weeds such as crabgrass, and reduced survival of young turfgrass plants when summer heat and drought begins. Although many people seed at the proper time, put much effort into proper soil preparation, and have selected quality seed or sod, some still find that the end product is not what they anticipated. Often, this failure is due to the initial lack of proper care after the seed has been sown.
Proper care during the first two months of establishment is essential to obtaining a healthy, dense turfgrass stand that is resistant to weed encroachment and other problems. Most of the necessary steps are based on common sense but are often overlooked by homeowners. By following the following basic guidelines, the chances for establishing an attractive lawn with reduced pest problems will be greatly enhanced.
Thus, reduction in watering may take place at an earlier date than slower germinating and growing grasses, such as Kentucky bluegrass. However, seed is often sold that contains several types of grass. If a seed mixture contains both quick and slow establishing types of grass, care must be taken to maintain adequate moisture until the slower growing grass becomes well established.
For areas where irrigation is impractical or impossible, it is essential that a good weed-free mulch be used to reduce loss of soil moisture. Even with a mulch, however, loss of some seedling turf should be expected during adverse environmental conditions if no water is applied. A subsequent overseeding of thin areas may then be necessary.
Although not usually a problem, excess water from either rainfall or irrigation can also lead to problems. The most common problems encountered are soil erosion, ponding of water which leads to suffocation or scalding of young grass, and disease problems in the late spring or summer months.
Avoid watering past the point at which the water will infiltrate the soil and it starts to pond or to run off the site. This point will occur sooner on clay soils and compacted soils. Also, in the late spring and the summer, avoid watering during the night. Several seedling diseases that can kill entire stands of young grass are substantially worse when leaf blades remain wet throughout the night.