Washington State University Extension

Garden Tips


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written September 6, 2015


This summer was tough on many area lawns, especially those where watering was restricted. Owners of ravaged lawns are wondering what to do now.

The first thing to do is assess the damage. Are spots and areas truly dead or did the grass just go dormant? With cooler weather and more water available, dormant grass should be starting to show signs of life. Check the brown areas closely looking for new grass blades. Once water becomes available, grass that is dormant greens back up within two weeks.

If no green growth is apparent and patches are a crispy yellow-brown or a grayish color, it is likely the grass is completely dead. Fall is a good time to re-seed or re-sod those areas, as long as irrigation water is available.

Because it takes some types of grass seed, like that of Kentucky bluegrass, up to two weeks to germinate, seeding must be done early enough to allow time for the seed to germinate and grow mature enough before hard frosts occur and before irrigation water is turned off. The average date of the first hard frost in this area is October 15th (note this is only an average date), so lawns must be seeded in early September. Re-sodding can be done later in the fall, as long as water is available and the soil is not frozen.

Water is critical to the success of both re-seeding and re-sodding. The soil must be kept moist to enable germination and provide moisture for root growth. If water is not available, you will be wasting time and money.

If more than 50 percent of your lawn is dead, you will probably want to consider complete renovation. You must get rid of the dead grass and any thatch before you can re-seed or re-sod. Seed and sod roots must be in touch with bare soil. Do this by mowing as low as possible and then using a rake, dethatching machine, or sod cutter to remove grass and thatch. Once you have bare soil, apply a starter fertilizer and the seed at the recommended rates on the labels and then rake the seed into the top of the soil.

If “only” 25 to 50 per cent of your lawn is dead, complete renovation can be avoided with over-seeding. First mow the lawn at a height of one and a half inches. Then you will need to rent a machine called a slit seeder or find a lawn care company who can come in and do this for you. The slit seeder cuts down through the grass and thatch and into the soil, dropping grass seed into the slit it creates. If you do this yourself, make two passes over the area in opposite directions. Check to make sure the seed is ending up planted at least 1/4 deep in the soil. Finish up with an application of lawn starter fertilizer and a light raking.

Next, moisture is needed to promote the germination and growth of the seedlings. This can be tricky as you need to water frequently enough to keep the soil moist but not too wet. Excess moisture can lead to disease problems. Once the grass germinates and plants develop several leaves, you should water more deeply and less frequently.

For lawns that survived the heat and are still green and growing, fall is the best time to fertilize. Apply fall lawn fertilizer in early September and again in early November.

Garden Tips, WSU Extension, Benton County, 5600-E West Canal Drive, Kennewick, WA 99336-1387, 509-735-3551, Contact Us

WSU Extension, Franklin County, 1016 North 4th Ave, Pasco, WA 99301-3706, 509-545-3511, Contact Us
© 2017 Washington State University | Accessibility | Policies | Copyright | Log in