Watering St. Augustine?

Discussion in 'Irrigation' started by Sunstate Lawn, Apr 7, 2008.

  1. Sunstate Lawn

    Sunstate Lawn LawnSite Member
    Messages: 143

    Will it make a difference if I change the zones on my time to run 2 15 minute waterings rather than 1 30 min watering? Right now it is set to run twice a week for 30 min per zone. I am being asked to change it to 4 times per week (same days) for 15 min per zone. I can't find any good reason to do this.

    It's for 2 18 zone panels.
  2. AI Inc

    AI Inc LawnSite Fanatic
    Messages: 27,092

    If it is a sandy base the shorter more ofton is the answer. If you have a lot of loam ( I doubt in Fla ) longer less ofton.
  3. EagleLandscape

    EagleLandscape LawnSite Platinum Member
    Male, from Garland, Texas
    Messages: 4,350

    What is the head type and precipitation rate.

    While you want deep root watering, you don't want to put on so much so you will soak the soil and lose alot to evaporation.

    You also don't want to teaspoon it, where you put on so little each time, it never soaks in deep enough.

    Here is what you need to figure out. How much water does St. Augustine need a week in your area. Once you know that, figure out how much water your sprinkler system puts out per hour. That will determine your run times.

    Messages: 18,668

    Do you consider root zone depth? The shadier the area the more shallow the roots the more frequent the watering need. I personally think the deep infrequent watering has resulted in more waste and poorer results. Once the turf root zone area dries out it doesn't matter that it is still moist 12" deep if all the root zone is in the top 4-8". i also think that turf is very susceptible to soil temp. Once that temp gets to 85 or above it struggles. i have an SMU sorority house that is covered by oaks and fescue is the only turf that survives. We water twice a week and do a 3 minute watering everyday at 3pm to knock the soil temp down in the summertime. Place looks really good considering all the shade.
  5. Kiril

    Kiril LawnSite Fanatic
    Messages: 18,335

    I agree with Fimco in part. Watering should be done based on your effective root zone + leaching requirement + reasonable reserves (which won't be much in sandy soils).

    I might agree on the 3 min watering to knock down soil temps if a need is determined, but you do realize almost all of that water will be lost to evap.

    Messages: 18,668

    I agree on the evap. It keeps them from running it everyday and it does make a difference. On the golf course we used to syringe our cool season greens in the summer. Obviously this is a bad application for turf in general.
  7. Kiril

    Kiril LawnSite Fanatic
    Messages: 18,335

    Yes, daily runs = boooooooo

    I'm assuming your 3 min run is for sprays only?

    I will also add that watering based on what a turf "requires per week" is not good practice. Irrigation is much like organic management, where you feed the soil, not the plant. Same goes for watering -> replenish soil water reserves as needed, not on a generic weekly plant use value. :)
  8. Sunstate Lawn

    Sunstate Lawn LawnSite Member
    Messages: 143

    We can only water on sunday and thursday here, between 4 pm and 10 am. What I am being asked to do is change the zones to run twice at 15 min instead of once at 30 min. Since there are 18 zones, we are talking about 9 hrs of run time. If I changed it to 15 mins, it would be 4.5 hours of run time back to back.
    Does this make sense? The person asking me only knows enough to randomly ask questions.
  9. CreationWilmington

    CreationWilmington LawnSite Member
    Messages: 7

    I think you're asking if you change it to 2 15 minute run times, will it hurt anything. My answer would be no. You're putting down the same ammount of water regardless. Actually with multiple run times to deliver the same ammount of water, you're eliminating run-off, and water exceeding root zone depth. During the hours given, you don't run any real risk of excessive evaporation. If it makes your customer happy, go for it. Not gonna hurt anything, and may even help conserve some water by keeping it in the "sweet spot" instead of running along the roadside.
  10. DanaMac

    DanaMac LawnSite Fanatic
    Messages: 13,231

    Welcome Creation. Good answer, but you'll see that we all get off topic in here and answers will stray. Keep up the good suggestions.

    Another thing to try, is set it for 12 minutes twice instead of 15. With the 30 minutes you may get some run off as the ground gets saturated. So the split times may be just as good at 12 minutes totally 24.

Share This Page