Overseeding Lawns for Winter
Should I overseed my lawn for the coming winter season? Lots of people employ this strategy, most of them in the interest of having a green lawn in an otherwise bland landscape. There are several pluses to overseeding warm season grasses with annual rye for the winter season, but also some elements that may give one pause in considering this.
Advantages to overseeding
On the plus side, your grass will be a brilliant green and it will set off your house in a very positive way. Next, these grasses are soft and have appeal to those who long for the days of wandering barefoot through the cool-season lawn grasses of northern climates. Third, cool season grasses require little care and don’t seem to have issues with diseases or insects that so frequently plague our warm season grasses. Fourth, I have often used annual rye as a winter cover around my horse barn and paddocks and have found it does a marvelous job of crowding out winter weeds. After a few years of rye cover, many of these weeds have disappeared; they simply can’t compete with the thicker annual rye. Finally, nothing needs to be done to remove this grass – once the temperatures of mid-May move beyond the 90°F mark the grass will simply die out. Its disappearance is almost imperceptible and by June you will never know it was there.
Drawbacks to overseeding
There are some drawbacks to winter overseeding one should consider carefully before deciding to move ahead with this. First, it will need some irrigation, particularly during the establishment period. Once the grass gets going it won’t need much supplemental water, but it is the dry season and usually November is dry, followed by some rains in December, January and February in normal years. If we have dry weather in December and January you probably will need to irrigate on a minimal level to keep annual rye healthy.
Next, there is some work to get the grass established, and preparation and irrigation are key factors in success. Third it does grow, so will need to be mowed infrequently during the winter season. The good news is that it is infrequent and mowing isn’t so bad when temperatures peak in the 70s. Finally, there are some who argue the annual rye slows the break from dormancy of the warm season grasses in spring. While I haven’t observed this on lawns in Florida there is an article from Clemson Extension that discourages overseeding of home lawns for any grass except Bermuda. Remember that climate conditions in South Carolina are much different than Florida and may account for recommendations against this practice. On my own bahia pasture areas I have not observed any problems for the established grass as a result of competition from annual rye.
If you decide to move ahead with winter overseeding, preparation of the site will be a key element in getting a successful stand. Be sure to purchase quality seed from your local feed or hardware store. Buy early as stores sometimes run out of this product. Check the label to insure the rye was harvested for the current season and check the germination rate to be certain it is 95% or greater. Stores sometimes run out of this product, so purchase early and store the seed in a cool, dry location, in a container to prevent damage from rodents.
As a first step in preparation mow your lawn at a height lower than normal, but not so low as to stress turf. St. Augustine, for example, should be cut at a height of three inches. For this last cut of summer, plan to bag and remove clippings or plan to rake clippings to give the rye seed a better chance of reaching the soil. Using a broadcast spreader, apply annual rye seed immediately after mowing at a rate of 7 pounds per 1000 square feet of lawn.
Rye needs cooler soil temperatures to germinate, so waiting until mid – late November is important in Marion County. If possible, I like to apply rye just before we receive rain – a gentle rain resulting in a quarter to a half inch is ideal, if you can perceive the weather forecast. Avoid seeding when heavy rains are projected. Rye seed is light, so avoid application when breezes are active. Early morning is a good time to apply to avoid windy conditions. Walk in one direction to sow half the seed and then walk in a right angle to the first side to sow the other half. As an added insurance step, to be sure the seed reaches the ground, some recommend lightly raking or running a stiff broom over the seeded area to complete the seeding process.
Watering is important and must be done daily until the seed germinates – usually about a week. Seeds must have moisture to germinate, so a light application of water, running your system to apply one quarter of an inch a day, preferably in the morning, is essential. Continue to apply approximately one quarter inch of water until the stand is fully established, about three weeks. Take care not to overwater which washes away seed and encourages disease development.
A winter cover has some benefits, particularly in the appearance of your lawn, but there are also drawbacks to consider. Overseeding takes some preparation effort and some attention to the irrigation schedule the first three weeks. Be sure your calendar allows you the time to attend to the needs of this venture before you decide to do it.