Grass (the lawn type :D ) advice needed!

[hhfarang]

Are there any lawn experts out there? Here's my story:

I have a rather large garden (rai and a half) that is mostly grass (lawn) of the same type (I believe) that you see on the better golf courses here. I am between full time gardeners at the moment as I fired one and the next one can't start until March 1st so I borrowed my neighbor's gardener for the few interim days. We have always watered every day when it is not raining and this requires a full time gardener along with the trimming, mowing, etc.

This temporary guy worked yesterday and went home and told his boss that we were watering too much and wasting our money. He said that we only needed to water three times a week and a good gardener could do that and keep everything else neat and tidy as well instead of having a full time person and watering every day.

Now, my question is: In this hot dry weather is watering three times a week really ok. It seems to me that the grass starts to brown very quickly when we skip a day but this guy swears that even the golf courses only water every other day and their grass stays green. He said that we are actually weakening our grass by over watering it (whatever that means).

I know people here that water their grass twice a day so I don't know what to believe now. Am I really wasting a lot of money on a full time gardener and 1000 baht per month water bill or does the grass really need this much water?

(I know this will be considered a dumb question by many of you but I don't do gardening so have always taken my wife's advice on how to keep it up.)

[Winkie]

My understanding is that watering too frequently causes the roots to accumalate around the surface of the soil, making the grass incapable of drawing water from deeper in the soil (which remains moist loner).

Watering less frequently causes the grass roots to grow deeper, into the area that remains moist longer. Therefore the grass is needs watering only every 3 days or so (or even longer).

Not sure if its really correct, but makes sence, kind of!.

Maybe you can slowly increase the intervals.

I water my lawn only 2-3 times a week during the dry periods, and it remains very green, and now 5 years old. However, my grass is the Malay type which may require less watering.

[PeteC]

I have the same type grass as you HHF and about 3 times a week is enough. I do the watering myself and we have a crew of 6 come in every other Sunday for 3 hours to cut, trim, turn dirt in the beds etc. That seems to be enough as things stay picturesque for just about 12 days between cuts/trims before it starts to look a bit ragged. We pay them 1,500 per service.

Back to watering. I simply move sprinklers to different spots each day which has the effect of locations getting repeated about every 3 days.

Fertilizer is important but I would stay away from the pure nitrogen. Just a bit too much and you get burned spots that take 2 weeks to regrow. Every 2 months I use a pellet type that is sold to put on non-flowering bushes. I decided to try it on grass and it works great as it has the chemicals grass needs as well and doesn't burn it. Since using it the grass has thickened and roots much deeper and stronger. I'd give you the name but I don't know it. It's sold in bulk in hand stuffed plastic bags but if you ask for fertilizer for non-flowering plants they should know what to give you. The pellets are bluish in color and it's not chicken manure based but a chemical concoction. Pete

[hhfarang]

Thanks for the good responses guys. I guess maybe I am wasting a few grand a month over watering and overpaying for a full time gardener.

The missus does the fertilizing and she buys something that is supposedly natural, not chemical, that doesn't have a tendency to burn the grass. She seems to know what she's doing in that respect as about once every three months when we mow very close (nearly scalp it) to the ground and she fertilizes, the grass always comes back a lot greener.

But it is also she that thinks it needs to be watered daily...

[PeteC]

Here's some more tips from the internet. Pete

Water deeply to encourage deep root growth. Frequent shallow waterings encourage weed germination, and they also cause the grass plants' roots to grow shallow, leaving the plant more susceptible to drought and to certain diseases. Watering only when your grass really needs it encourages the roots to grow deeper, but only if you apply enough water each time to penetrate the root zone. The most accurate way to determine the depth of the root zone is to dig a small hole and measure how far the roots go down. Alternatively, you can follow these general approximations: if you have a bluegrass lawn, each watering should moisten the soil to 6-8 inches, while for most other grasses, the water should penetrate 8-12 inches. You can determine how long to leave the sprinkler(s) on by using one of the following methods.

Turn on your sprinkler for 15 minutes. After 18-24 hours, find out how deep the water soaked in by digging a small hole in the watered area or using a probe (a probe will push easily through damp ground). You can also push a shovel into the ground and use it as a lever to spread the soil apart enough so that you can see several inches below the surface. Once you see how deep the water went in 15 minutes, you can calculate how long you need to leave your sprinkler on. For example, if the soil is damp to 4 inches below the surface and your goal is to moisten the soil to a depth of 8 inches, you'll need to leave the sprinkler on for 30 minutes (2 X 15 minutes) each time you water.
Estimate how much water you'll need based on your soil type. In general, 1" of water will penetrate sandy soils to 12", loamy soils to 6-8", and clay soils to 4-5". Using these estimates isn't quite as accurate as digging, but it's pretty close, especially if you have a good knowledge of your soil composition. To figure out how long you need to keep your sprinkler or sprinkler system on, calibrate your sprinklers.
______________________

..and another one: http://www.lawncareguide.org/watering-your-grass/

[Nereus]

Most Thais will tell you that you have to water every day. They will also tell you that you should do it during the heat of the day!

There are many variable factors involved to determine the correct water requirement, as pointed out above. But one of the base things that should be looked at is: "Evapotranspiration"
Look it up on the Internet, as it is too vast of a subject to write here.

One of the biggest wastes of water is due to direct evaporation from watering during the heat of the day. There has been a lot of research done in Thailand on the use or water for irrigation, initiated by HM the King. And although it really does not concern domestic gardens, the principles are the same.

I will copy some stuff that I had advice on:

"I can only tell you evaporation rates from open ponds which is approx. 1 cm per day in the dry season. (I read that from an estimate that the King had done for Northeast Thailand.). What you are probably looking for is evapotranspiration. I think it would be near impossible to give a real watering requirement for your garden without being there to watch the soil and plants. If you were looking around for a way to spend your money, you could invest in one of those high-tech potentiometers for measuring how fast the soil dries out and link it to an irrigation system. (bit far-fetched I think!)

Here is something that might give you an idea but you will have to take into consideration the types of trees, depth of soil, type of soil, humidity etc.:

"This study was performed to examine seasonal changes in evapotranspiration (ET), soil water content, and crop coefficients (Kc) for sugarcane, cassava, and maize fields in Northeast Thailand. ET rates during the rainy season varied between 2 and 6 mm per day but remained around 1 mm per day in the dry season. The normal dry season ET was much greater than the water loss from the top 0.5 m of soil, suggesting that capillary rise from deeper soil layers provides significant amounts of water to the upper soil layer. The Kc for sugarcane and cassava reached growing season peaks of approximately 1.10 and 1.20, respectively, in June. The maximum Kc for the maize field was approximately 1.20. Although the ET estimated by the Hargreaves equation exceeded the FAO reference ET value for this region, the values had a high correlation when the Hargreaves ET was calculated using solar radiation measurements."

" I would recommend you have the water on once in the morning for 5 or 10 minutes depending on coverage and saturation rates. Timing should be around 4am so it gives the water time to soak in before the sun comes up. 5 or 10 minutes again in the evening after the sun goes down. Certainly don't water during the day as at least 50% of the irrigation water will go to the air."

"The grass shouldn't need as much especially if you can get the grass roots growing down a meter or so. The golf courses say the root systems on the greens can go down at least a meter but then that is in sandy conditions.
Trial and error is probably going to be your best bet."

The above info was given to me by an expat agricultural scientist that lives and works in Thailand.

[hhfarang]

Thanks again for all the good info. Looks like some field research will be in order.

Nereus,

Yes, I've always known that watering around 4 a.m. is best to let the water soak in before the sun comes up to evaporate it and also the droplets on the leaves act like little magnifying glasses with the sunlight to burn the grass, but in the U.S. I had automatic pop-up sprinklers on a timer so that was easy. When I built my home here those were not available so it has to be watered manually and I have not found a gardener who wants to start work at 3 or 4 a.m.!

So my lawn is always watered in the hottest direct sunlight.

[BaaBaa.]

Always do mine at about 6pm.

[Khundon1975]

A good top coat of mulch also helps to keep the moisture in. I'm sure you could get chopped bark or coconut husks that would do the job and help to cut down the need to water so often.

No good on lawns though.

[PeteC]

As a side comment, now that the trees and foliage are starting to mature at our place after almost 3 years, we're finding certain areas that are now too shaded for grass to grow no matter what you do to it. The entire area east of our house next to our wall and the north side of our pool sala are scheduled for grass removal, sanding, sealing and curve angle interlinked brick installed. Should (hopefully) look nice after it's done. Wife already has plans for tables, chairs and other decorations in one of the areas. I think she want's it to look like an outdoor cafe. Will post pics when finished in March sometime. Pete

[BaaBaa.]

The entire area east of our house next to our wall and the north side of our pool sala are scheduled for grass removal, sanding, sealing and curve angle interlinked brick installed. Should (hopefully) look nice after it's done.

AKA Pattaya.

[PeteC]

AKA Pattaya.

You're right, a mini Walking Street. Maybe I'll put up a chrome poll also and invite bored housewives over to audition. Pete

[Nereus]

Thanks again for all the good info. Looks like some field research will be in order.

Nereus,

Yes, I've always known that watering around 4 a.m. is best to let the water soak in before the sun comes up to evaporate it and also the droplets on the leaves act like little magnifying glasses with the sunlight to burn the grass, but in the U.S. I had automatic pop-up sprinklers on a timer so that was easy. When I built my home here those were not available so it has to be watered manually and I have not found a gardener who wants to start work at 3 or 4 a.m.!

So my lawn is always watered in the hottest direct sunlight.

I installed an automatic reticulation system at my house in Hua Hin a couple of years ago. All of the equipment is available now, including "Nelson" American made controllers. I did it myself after running off a so called "contractor". It has a 9 zone controller, of which two are not in use. The lawn pop-ups get 10 minutes, and the spray lines around the walls get 5 minutes. It has a rain sensor that shuts it down if it rains. It is programmed on for 4-00 am and has a battery back up in the controller so it does not loose the time with a power failure.

I do not agree with the comment that was made to me about running the sprinklers in the evening, as this can lead to fungus growth, etc.

Regarding your comment about a gardener not wanting to start work at 4-00am, I have found that it is a problem to find a gardener that wants to start work AT ALL!

[hhfarang]

The lawn pop-ups get 10 minutes, and the spray lines around the walls get 5 minutes.

Nereus,

Now that my landscape is mature and I have lots of trees and sidewalks I think installing an underground pop-up system would be difficult and cost prohibitive with a garden as big as mine, but I'm interested in the spray lines around the walls you mentioned.

I've been thinking about this for a while and I have a drain approximately 30 cm wide that surrounds my property, just inside the wall. It is hidden from view by a line of low shrubs (some sort of flowering hedge) that we keep trimmed at about a half meter height. My property is long and narrow (28 meters wall to wall width) with lawn on both sides and driveway and walkways down the middle dividing it into two sides of lawn that (subtracting the cement) are no more than 12 meters wide at the widest point. I was wondering if there was a system that I could install around the perimeter of the wall at the level just below or near the top of the hedge that would shoot water in a 12 meter semicircle.

If such a system could be designed then I could install an automatic system around the perimeter without the need for digging. Do you think that's possible? I was thinking I could even use big pop-ups (if they will shoot that far and mount them just behind the hedges with them at the hedge top level when retracted (on a pipe that rises above ground. Then when they come on and pop up they would shoot over the hedge.

The other way I was thinking about was using the same method but mounting those big reticulating Rainbird sprinklers like golf courses use but also mount them on pipes rising from my drain area so that the sprinkler heads would fire over the hedges. I know that type would cover the distance I need.

[hhfarang]

Another idea that's been floating around in that back of my mind is to use the existing system of pipe and outlets that are already installed inside my wall around the property. I could use a sprinkler head that would mount horizontally instead of vertically that would stick out from the wall and spray or shoot water upward at about a 45 degree angle to clear the hedge, but I don't know if such a sprinkler head exists or is available here. The other way I thought about to use those pipes and outlets would be just to mount an "L" shaped pipe to each one and put some sort of sprinkler head (then mounted vertically) on top of the pipe at the hedge top level.

I just took these photos to show you what I mean. I have outlets like this (some with regular taps on them but they can be unscrewed and any type of outlet installed (like in the photo) spaced at 8 meter intervals all around the perimeter wall.