Warm Season Turfgrass Management

The information contained in this packet is designed as a general guideline for maintaining warm season turfgrass in Arizona and California. As with all living plants there will be unforeseen circumstances and environmental conditions that will require you to deviate from site to site. Maintaining turfgrass in the desert regions can present severe stress on turfgrass so daily observation is important. One plan is not going to fit every circumstance, but going into the season with guidelines will help ease the burden when situations arise.

Soil Preparation Prior to Sod Installation

1. Apply gypsum at 25-50 pounds per 1000 square feet to the area you will be getting ready for turf.
2. Rototill your soil to a 6-8 inch depth. This may not be possible in all areas but tilling up the soil as deep as possible will provide your lawn with more air, better water infiltration/percolation, and will allow for a stronger root structure.
3. Level and grade the soil to reestablish uniformity in the soil.
4. Install your irrigation system. It is important to make sure that all irrigation trenches are water packed and have fully settled before you put your lawn in. You don’t want to see where all the irrigation trenches were dug. Do you want to lower your water usage on turfgrass? Try a subsurface irrigation system. There have been so many advances in the drip irrigation market and we have had very good success.
5. Finish grade your soil and use sand to do any leveling to the soil surface. Mulch is okay, but it will hold moisture in the top couple inches of the soil and can potentially bring in weed seed. Sand is the ideal growing medium for grass.
6. Water your soil for a few days to make sure the soil is settled and you’re happy with the final grade. Remember sod is just like carpet and anything under the grass like large rocks will be visible.
7. Order your BOBSod and set up a day to install the turf. Don’t forget to order your Soil Burst 4-4-2 organic starter fertilizer from us that can be applied right before the sod goes down or right on top of your new lawn. Don’t miss this critical step. Other starter fertilizers that can easily be applied are 11-52-0, 6-24-24, 21-7-14, or 6-20-20. There are several other kinds but these are the most readily available in town.

Installing West Coast Turf

1. Lay sod around the perimeter using small cuts in the sod to help wrap around tight corners.
2. Find the longest and straightest point in your lawn and lay the sod in a straight line.
3. Now follow the straight line and sod in a brick pattern to stagger the seams. The easiest way to do this is to cut the first piece of sod in half and then lay full rolls. This will keep the seams from lining up next to each other.

Watering Your New Turf

1. Water 3-4 times a day for the first two weeks making sure you keep the foliage of the grass moist. Since roots have not been established it is not important to water more than 10-15 minutes per cycle.
2. Once the grass has rooted down (can’t be pulled up) cut your watering to one time per day for 15-20 minutes. If you have low flow sprinklers you need to water twice as long as a normal pop up sprinkler.
3. Once the lawn has been in a month cut the watering back to every other to every third day for 25-35 minutes. This will be your summer watering schedule. Grass should be watered deep and infrequent to promote root growth.

Turfgrass Fertility

Fertility is one of the most important aspects of maintaining a healthy stand of turf. Fertilizers come in all different formulations and the only true way to determine requirements is to do annual soil testing. All bags of fertilizer list three numbers on the front of the bag. These are nitrogen, phosphorus, and potassium. These three nutrients are the key building blocks to every successful fertilizer program.

Nitrogen (N) – Nitrogen is one of the most essential nutrients to all grass plants. It is required in the highest quantities for all warm season grasses except paspalum. Bermudagrass will use 8-10 pounds of N per 1000 SF (350-450#/AC) during the growing season. The typical growing season is from mid-April through November. Nitrogen is the first number listed on a bag of fertilizer. (e.g. 21-0-0)

1. Color
2. Shoot growth
3. Density
4. Wear tolerance
5. Recuperation of injured or new turf

Quick release Nitrogen sources:

1. Ammonium sulfate
2. Ammonium nitrate
3. Potassium nitrate
4. Urea

Slow release nitrogen sources:

1. Sulfur coated urea
2. Compost and manure (miloraganite)
3. Poultry waste – (Soil Burst 4-4-2)
4. Resin coated urea
5. Urea formaldehyde

Phosphorus (P) – This is one of the key nutrients along with nitrogen and potassium that is essential for plant survival. Phosphorus is the second number listed on a bag of fertilizer.  (ex. 11-52-0) It has been proven to help with quick lawn establishment because it promotes strong root growth. Most bermudagrass lawns use between 4-6 pounds (175-250#/AC) of phosphorus per 1000 SF growing season.

1. Turf establishment
2. Root growth
3. Seed production
4. Increased turf vigor

Potassium (K) – The final nutrient in the big three listed on a bag of fertilizer (ex. 21-7-14). Potassium is required by all turfgrass plants for plant strength and root formation. A potassium deficiency can be identified by yellowing of the turfgrass leaves, weak root system, and it opens up the plant for disease potential if conditions are right. A typical bermudagrass lawn will use 4-6 pounds (175-250#/AC) of potassium per 1000 SF per growing season.

1. Root growth
2. Heat and cold tolerance
3. Wear tolerance
4. Disease susceptibility

Sulfur (S) – Sulfur is typically used in smaller quantities in warm season turfgrasses, but it is a valuable nutrient for turfgrass managers. Most bermudagrasses will use 2.5-5 (100-200 pounds/AC) pounds of sulfur per 1000 SF per year.

1. Green color
2. Shoot growth and density
3. Root growth
4. Food storage (carbohydrate storage)

Iron (Fe) – Iron is an essential micronutrient that helps maintain balance in the plant. While it is not part of chlorophyll it is essential for chlorophyll synthesis. Iron has long been known as the key to solving many chlorosis issues.

1. Green color
2. Shoot growth
3. Root growth
4. Wear tolerance
5. Cold/heat tolerance

Calculating Fertilizer for Turfgrass

All fertilizer bags list N-P-K on the front of the bag. These numbers determine the percentage of these nutrients in the bag of fertilizer. Using your monthly nutrient requirement you can easily calculate how much N-P-K you will be putting out in an application.

Ex. A bag of 21-7-14 is made up of 21% nitrogen, 7% phosphorus, and 14% potassium. The remainder of the bag is micronutrients and inert matter. If you wanted to apply 1 pound of nitrogen per 1000 SF you would use the following formula.

1 pound of nitrogen /.21 (percent in the bag) = 4.76 pounds of product to yield 1 pound of nitrogen per 1000 SF or 207 pounds per acre (43,560 SF/AC)

After calculating the amount of total fertilizer needed you will want to calculate the setting on your spreader by weighing 4.76 pounds. Measure out 1000 SF and adjust your setting plus/minus depending on if you have extra or too little fertilizer.

Pre/Post-emergent Weed Control

There are so many herbicides on the market today that treat any number of weeds, but I have provided a list of the herbicides I’ve had the most success using. This doesn’t mean that a product I didn’t name won’t be effective, but unfortunately some of the others I have not done enough testing on.

Pre-emergent herbicides

1. Barricade 65WG (Prodiamine)
2. Dimension (dithiopyr)
3. Ronstar (oxadiazon)
4. Pendulum (pendimethalin)

Post-Emergent Weed Control

1. Trimec Classic for bermudagrass overseeded with ryegrass.
2. Trimec Southern for paspalum lawns overseeded or not overseeded with ryegrass.
3. Vanquish (Dicamba) safe for bermudagrass and paspalum overseed/non
4. 2,4-D Amine – Safe for bermudagrass lawns overseeded/non
5. Xonerate (Amicarbazene) – This can safely be used on ryegrass to control Poa annua in a bermudagrass or paspalum overseed/non.  See label for rates. Best used in two half rate applications split up a month apart.

Before making an application of a pre-emergent herbicide make sure you take a look at the following:

1. Irrigate afterwards, water activates pre-emergent herbicides.
2. Measure your lawn surface area and calibrate your spreader properly prior to application. Applying more herbicide than is necessary could cause damage to your lawn.
3. If you are starting to see a little emergence of crabgrass or poa annua after the product has been applied it is okay to make a second application of some products over the missed areas. Consult with the label prior to making a second application.
4. If you have recently installed your turf (within the last 3 months) you should withhold all pre-emergent herbicide applications so you do not damage the root system.

It is extremely important to error on the side of caution when using any herbicide. Using more product than the label states is not only against the law it can also be very harmful to the turf. If you over apply herbicide you can expect to see residual damage for a few months after the application.

If you have a dormant lawn and are looking to get rid of poa annua before the bermudagrass or paspalum season apply Revolver, Kerb, or Certainty to remove.

There is a 2-3 week window between mid-December and mid-January after a hard freeze when you can apply round-up to treat weeds in dormant turf. The round-up rate should not exceed 16oz/ AC and needs to be applied before any spring green up.

Nutgrass herbicides

1. Sedgehammer
2. Certainty
3. Monument
4. Sandea

Overseeding

1. Raise your mowing height up for a week so when you get ready to scalp the lawn you’re not mowing it down to the nubs. You want to raise the height 25-30%.
2. When the nighttime temperatures consistently stay below 65 degrees (usually early to mid-October) you’re good to begin the overseed process.
3. Rent a Ren-o-thin or dethatcher (usually $40-$50 for 4 hours) and drop the setting to just below half way. You don’t want to get aggressive and take out roots; you’re just looking to open up the grass canopy. Since warm season grasses tend to be thick at this time of the year a lot of grass will be taken when you verticut or dethatch.
4. Verticut or dethatch in two-directions making sure your turf grass is open.
5. Set the mower one notch below your last mow and pick up all of the grass lying on top of the ground.
6. Now drop the mowing height one additional time and make sure you remove all of the remaining material that was lying on top of the turf.
7. Apply your Soil Burst 4-4-2 starter fertilizer at 15 pounds per 1000 SF.
8. Apply BOBSeed at 8-10 pounds per 1000 SF. I like to use a drop spreader to do two passes around the edges and keep the seed out of the rocks and dirt. Then come back with a rotary or drop spreader for the remainder of the yard.
9. Since you verticut the lawn two directions you have opened up the grass plant and the seed will come up in a nice checkerboard pattern.
10. Set your sprinklers to run 3-4 times per day for 5-7 minutes.
11. Your lawn will germinate in 5 days and you will see grass starting to pop in 7-10 days.
12. When your turf is 14 days old apply 21-7-14, 6-20-20, or 11-52-0 to your lawn.
13. Make your first cut at 14-17 days when the grass is 1.5 inches. Do not cut a lot of material. Just trim it up. It is important to mow the grass when the turf is dry to get a clean cut.
14. Change your watering to 1x per day for 10-15 minutes first thing in the morning for two weeks.
15. At one month apply a final granular application such as Soil Burst 5-15-10, calcium nitrate or spray ferrous sulfate and potassium nitrate
16. Decrease your watering schedule to every other to every third day for 20-25 minutes.
17. Apply Soil Burst 4-4-2, 7-7-7, ferrous sulfate, or potassium nitrate every month throughout the winter.
18. Granular fertilizers will not work well once we receive significant frost so make sure you use liquid products and keep the color bright green.

Spring Transition

1. Gradually lower your mowing heights to reduce the turf canopy. Warm season grasses are not shade tolerant and excess ryegrass provides shade.  No need to scalp the lawn, just lower the height down and begin to thin out the grass.
2. Lightly verticut the lawn to open up the canopy and let sunlight into the grass below.
3. Be careful of fertilizer rates at this time of the year and stick to slow release products such as Soil Burst 4-4-2, 11-52-0, 6-20-20, or 21-7-14. You want to put a pound of nitrogen per 1000 SF down when you make this fertilizer application. The first number on the bag is nitrogen and it is listed as a percentage. For example the 21-7-14 is 21% nitrogen. A typical fertilizer bag weighs 50 lbs so 21% of the 50 pounds is nitrogen. In other words you have 10.5 pounds of nitrogen in a 50 lb bag. Since the goal is apply one pound of nitrogen you would use the following formula.
4. 1 pound of nitrogen / .21 (percentage of nitrogen on the bag) = 4.76 pounds of product per 1000 SF will yield 1 pound of nitrogen.
5. If you have standing water it is a great time to aerify so you can help air and water better infiltrate the soil.
6. Increase your mowing frequency to two times per week.
7. Gradually back off the water this month to stress out the ryegrass when soil temperatures reach 64 degrees (usually around mid-April). Turning off the water completely will stress out the warm season turf and ryegrass so this is not the optimal approach. Use 60% of your normal water rate.
8. When soil temperatures reach 64 degree apply Soil Burst 5-15-10 at 20 pounds per 1000 SF to give the grass a jump start on the year. A second option to this is to use ammonium sulfate 21-0-0 at 5 pounds of product per/1000 SF.
9. Fertilize with 1-2 pounds of nitrogen per 1000 SF monthly over the summer. You can use any combination of the products I listed above as well as several others to help you achieve your goal of a perfect lawn. For a more accurate analysis on other nutrients you can send soil samples into a lab for results.

Watering

99% of all issues related with turfgrass in our area are related to water. While many assume that too little water is always the problem, overwatering is just as detrimental to turfgrass. It is extremely important to check your turf daily to determine water use. Even when temperatures reach 115 degrees in the summer it is still possible to overwater your turf. Below are the key principles to a healthy lawn followed by new sod watering guidelines:

This pictures shows a dead area right in front of a pop up sprinkler. A dual fan nozzle will solve this common problem. A dual fan will throw water out and also hit the spot in front of the sprinkler.

1. Water enough to moisten as much of the root zone as possible. Using a soil probe you can determine how deep your root zone is. Water to the depth of the roots.
2. Water deep and infrequently. Do not water your turf every day.
3. Sandy soils require more frequent irrigation and the root zone is often deeper than a clay material.
4. Clay soils can be watered less frequently with larger quantities of water.
5. A typical bermudagrass lawn will use 1” of water a week during the summer months. This should be applied over 3-4 days.
6. In order to successfully water deep and infrequent utilize the cycle/soak method of irrigation. If you need to run 40 minutes then water 20 minutes at 6:00 am and 20 minutes at 9:00 am.
7. Water early in the morning to reduce environmental factors such as wind, evaporation, etc.

New Sod Water Guidelines

Turfgrass cultural practices

Both aerating and verticutting will help reduce soil compaction. This is one of the biggest contributors to turfgrass desiccation. Soil compaction not only effects soil oxygen levels, it also plays a major role in the root system, deters the plant from accessing many of the key nutrients, and is a major contributor to weeds.

As with any maintenance program attention to detail is always important. In order to maintain a healthy turfgrass plant year round I would suggest incorporating the following into your yearly plan:

Verticutting or Dethatching (power raking): Light verticutting can promote new growth, reduce thatch, and help with early spring green up by letting air move in the root zone. I highly suggest verticutting prior to overseed to open up the grass plant. Opening up the plant allows the seed to get inside the grass reducing the amount of seed that fails to germinate.

Aeration: Helps relieve the root zone of compaction while controlling thatch. Opening up the pore space in the ground helps with water infiltration/percolation and also improves air flow.

Here is a link to a video on verticutting/power raking:

https://www.youtube.com/watch?v=B8p5R_sowbI

Varieties of warm season turf

1. Paspalums (Platinum/Sea Spray)
2. Darkest color of any of the warm season turfgrasses
3. Can be mowed between 1/10th of an inch and 2 inches with a rotary or reel mower
4. Highest salt tolerance of any warm season grass which means it can tolerate high sodium water sources such as effluent water
5. Shortest dormancy period of any of the warm season grasses (often as little as 2-3 months)
6. Full sun between 9am and 3 pm
7. Uses 2/3rds the nitrogen as bermudagrass (stick with the Soil Burst products for low nitrogen, high calcium applications)2. BOBSod
8. Most popular homeowner/landscape variety on the market
9. Deep blue/green color
10. Maintain between ¼” inch and 1.5 inches with a rotary or reel mower
11. Uses very little nitrogen, has virtually no seed heads, and is a slow growing turf which means less mowing
12. Soft, carpet like feel

1. EZ-Turf (Arizona)
2. Perfect grass for low maintenance lawn
3. Open turf canopy which makes it ideal choice for rotary lawn mower
4. Coarser leaf blade than BOBSod or Tifway
5. Medium green color and fast growing turf
   4. Tifway II (California)

1. Medium leaf texture
2. Shortest dormancy period of any of the bermudagrasses
3. Maintain between 3/8” and 1” with a sharp rotary or reel
4. Very dense growth habit with dark green color

Tifway 419/Tifgreen 328

1. Very dense turfgrasses with medium fine leaf texture. Tifgreen 328 has shorter internodes which allows it to be maintained lower.
2. Aggressive growth habit and requires full sun
3. Best maintained with a reel mower but Tifway 419 can be mowed with a sharp rotary
4. Excellent sports turf with a soft surface

St Augustine

1. Coarse bladed, plush growing turfgrass that does well in the shade or ideally full sun.
2. Can be maintained with a rotary or a reel
3. Dark green color in the summer months but should be left dormant for the winter months

Pets are as much a part of our families as our kids and keeping them happy is important.

Do you know what makes for a happy dog? One of the best ways is by putting in a new lawn. Did you know that putting in grass has been shown to reduce ground temperatures by as much as 30 degrees? We continually see a trend for people to use rocks in their yards because they don’t like the perceived maintenance of a yard but in this day and age it is important to think about the environment.

Sod cleans the air and helps recharge our groundwater supplies. Turfgrass is one of nature's finest and least expensive filters, and works to improve the environment. The front lawn of just 8 homes has the cooling effect of 70 tons of air conditioning. Just think how happy you and your pets would be to walk around during the summer months if everyone had grass in their yard.