Mixing Tall Fescue with Ryegrass

Discussion in 'Homeowner Assistance Forum' started by whitenack, Feb 28, 2007.

  1. whitenack

    whitenack LawnSite Member
    Messages: 78

    UK college of Agr. says not to mix tall fescue with ryegrass.

    My local feed & seed store recommended I mix them on a bare spot I want to establish.

    Who is right?

    What would happen if you did?
  2. MJS

    MJS LawnSite Bronze Member
    Messages: 1,316

    Hi Whitenack,
    I assume that you are talking about mixing tall fescue with annual ryegrass. Annual Ryegrass is very quick growing, and is used more as a "quick cover grass" to help slower growing varieties become established. Annual Ryegrass will die off after the growing season, hence the name. I see no trouble mixing this grass with tall fescue, however, you may run into problems (esp. in KY) mixing tall fescue (recommended mowing height 3") with Perennial Rye (recommended mowing height 1 1/2"), as they will likely cancel eachother out, and only one variety will really be healthy and thick in the long run.
    Hope this helps.
  3. whitenack

    whitenack LawnSite Member
    Messages: 78

    Ah, I see.

    I bet that is right. I bet it is annual ryegrass and I didn't know there was a difference.

  4. DiyDave

    DiyDave LawnSite Bronze Member
    Messages: 1,695

    Problem with ryegrass is that when it germinates in a mixture of over 10-15% ryegrass to other grasses, it produces a chemical which inhibits the germination of other grasses. Annual rye, that is. Leave it out of the mix.
  5. turf_toes

    turf_toes LawnSite Member
    Messages: 14

    The previous post is right on.

    There is research indicating that Ryegrass is allopathic in relation to other types of grass. In short, it emits a chemical that kills bluegrass and other types of seedlings.

    Also, because it tends to germinate faster, it will tend to dominate the resulting lawn -- even when the amount of rye grass is as little as 20 percent. (This applies to both annual AND perennial rye grass)

    Other studies have found that putting down 80 percent Kentucky Bluegrass seed and 20 percent Perennial Rye grass results in a lawn after one year of about 70 percent Rye.

    Despite cumulative seeding rates as high as 42 pounds of seed per 1,000 square feet over a 21/2-year period, no Kentucky bluegrass could be found in the intact areas of any of the plots. In fact, the only bluegrass to be found was in divoted areas that had been overseeded when the divots were still open. It was obvious that slit-seeding Kentucky bluegrass into healthy perennial ryegrass fairway turf, even with the use of a PGR to suppress ryegrass growth, was a totally ineffective method for introducing, much less converting, bluegrass into these fairways.

    It should be noted that we did see bluegrass seed germination in the fairways. Within a couple of weeks of seeding, bluegrass seeds were germinating in the seeder slits (approximately 1/4-inch depth). And some seedlings, although spindly and weak, did emerge from the slits. But the seedlings did not mature into healthy adult plants.

    Though discouraging, the results were not totally unexpected. Observations over the years by turf extension specialists, USGA agronomists, and many golf course superintendents have noted the general futility of overseeding bluegrass into established ryegrass turf.


    The url to the full article is here.
  6. SDlawn

    SDlawn LawnSite Member
    Messages: 8

    What about Annual Ryegrass that is regrowing?

    Last year I planted a lawn with Annual Ryegrass. We let it die, and did a substantial removal of trees and plants in our backyard. I removed a ton of roots, tilled the soil, mixed in some topper, installed irrigation and am getting ready to plant tall fescue.

    While testing the irrigation, the rye grass started to sprout. Even just a few days of 1 or 2 minute watering has it popping out all over. Do I need to kill this grass before planting the fescue? Will it prevent it from taking hold?

    If I do need to kill it, what is the best way?
  7. KerbDMK

    KerbDMK LawnSite Senior Member
    Messages: 745

    Annual ryegrass will only grow once, drop seed, and die. If you were mowing the ryegrass, it would not have been able to produce viable seed, so you really should not have annual ryegrass growing now. It may be some other kind of grass that you probably don’t want in your lawn anyway, so feel free to use a glyphoste product like Round-up and kill it before you seed your tall fescue.

    Be sure to follow the directions on the label and plant your seed after the amount of days the label says you can plant grass seed. The existing grass may not be quite dead yet, but you can still sow your seed at that time.
    Last edited: Nov 7, 2017
    SDlawn likes this.
  8. SDlawn

    SDlawn LawnSite Member
    Messages: 8

    Thanks! That is helpful. I will probably round up before I topsoil and level.

    I should also mention that the lawn from previous owners was sod, and I got down below that when I tilled.

    Maybe it is the grass from the sod?
    KerbDMK likes this.
  9. KerbDMK

    KerbDMK LawnSite Senior Member
    Messages: 745

    It could be, or it might be quackgrass, or some other kind of grassy weed too. If you want a nice, as weed free as possible, stand of tall fescue, it’s best to kill whatever is there before you plant your tall fescue.
  10. SDlawn

    SDlawn LawnSite Member
    Messages: 8

    Was it bad that I covered with topsoil a day or two after spraying?

    Also, I am seeing differing opinions on steps.

    I thought I should do the following:
    1. Cover with topsoil to level out uneven areas
    2. Use a roller to compress (the kind you fill with water)
    3. Seed
    4. Cover with topper lightly (or mix topper with seed and seed)

    Anything I am missing or that is in the wrong order?

Share This Page