Green Grass in the Winter – Overseeding

front-yardGreen Grass in Winter

Late September to mid-October marks a major milestone for turf landscapes in the desert. At this time, those who want to maintain green parks and lawns through the winter need to overseed Bermuda grass with winter Ryegrass.

Bermuda grass, which grows well in the summer, turns brown and goes dormant with the first frost and remains that way until spring.  Ryegrass however, stays green and vibrant through the cooler months, with the exception of heavily shaded areas, and will die out with the return of triple-digit temperatures.

Steps for Overseeding Your Lawn

1. Timing is critical. The ideal time to overseed is when nighttime temperatures are regularly below 65 degrees (typically mid-October). About 2 weeks prior to overseeding, reduce the amount of irrigation water to the Bermuda by about half. This will signal the Bermuda to slow its growth and store energy for the winter.

2. In order to successfully spread the Ryegrass seed, you need to prepare the seedbed for planting. Lower the mowing height on your lawn mower in several passes, taking off about ¼ inch each mow cycle until the grass is approximately ¾ inch in height. Make sure to remove the clippings by mowing with a bag-catcher or by raking them up. The goal for this process is to make sure the Ryegrass seed comes into direct contact with the soil.

3. Now you are ready for seeding. For the best results, use perennial Ryegrass seed. Use a rotary spreader or drop spreader to evenly distribute the seed at a rate of 8 to 10 pounds per thousand square feet. To maximize germination, lightly rake and then cover the lawn with ¼ inch of mulch. Apply a starter fertilizer (6-20-20 or 6-24-24) after the seed is down. Water the area after spreading the Ryegrass seed, and set your irrigation clock to water 3 to 4 times a day at approximately 2 to 5 minute cycles. This schedule ensures the soil and mulch remain moist, and not overly wet, until germination. This step should take 7 to 10 days.

4. After the seedlings emerge, reduce watering to once daily. When the grass reaches about 2 inches in height, it is time for the first mow. Cut the grass to about 1½ inch in height and fertilize with a 21-7-14 fertilizer. Make sure to water immediately following the fertilizer application. Depending on temperatures and rainfall, you can then reduce the watering schedule to once every 2 or 3 days. To keep your lawn from turning yellow, fertilize every 3 to 6 weeks with ammonium nitrate (34-0-0) or calcium nitrate. Apply all fertilizers according to the directions on the package.

Hand Spreader

Use a rotary spreader to distribute seed.

By following these steps, you should achieve a lush, green lawn through the winter months and into spring. When triple-digit temperatures return, it will be time to transition from the Ryegrass back to the Bermuda grass.

Turf Aeration

Beautiful, Healthy Turf

aerated turfTurf is an integral component of common area landscape. Its aesthetic qualities and value as a recreation surface make it a desirable part of many communities. Beautiful, healthy turf is always the goal in any maintenance plan, and this goal can only be attained with an intelligent approach to horticultural practices. Turf areas that are utilized frequently often suffer from soil compaction. Prolonged physical compaction of the soil results in a hard surface that does not allow efficient water penetration, oxygen absorption by the roots and movement of nutrients from the surface into the root system, which are needed for healthy turf. The effects of compaction can be mitigated by aeration, a valuable but often overlooked, horticultural practice that is a very effective tool for maintaining healthy turf.

Aeration Methods

Aerated TurfThe aeration process is achieved by different methods; all of them involve creating holes (3 to 6 inches deep) in the turf soil.  One common method of aeration involves forcing a solid tine into the soil through the use of gravity (weight), hydraulic down-pressure or vibration.  This is a fast, clean process in that no soil cores are removed and litter the turf.  Another method of aeration involves driving a hollow core tine into the soil and removing a small cylindrical-shaped soil “plug”.  These plugs are left on the turf surface and are broken up by subsequent mowing.  Golf course greens are aerated utilizing this method several times each summer.

The best time to apply soil amendments and fertilizer is immediately after aeration while the holes are fresh.  Amendments fill the holes and are quickly absorbed and distributed to the turf’s root zone.  Through aeration, water and oxygen penetrate the soil and roots and promote healthy turf. At home, apply a turf fertilizer after aeration to achieve the same nutrient balance in your soil.

Did You Know?

Compacted soils offer an ideal environment for a fungus known as Fairy Ring.

Fairy Ring

Wolf in Sheep’s Clothing: Nutsedge

Is It Grass?

turf_nutsedgePossibly one of the worst turf weeds to infest your lawn, Nutsedge spreads quickly and is extremely hard to eradicate. Nutsedge is the common name for Cyperus esculentus (yellow) and Cyperus rotundus (purple), a weed type that germinates well in warm moist soils and spreads through tubers (referred to as “nuts” or “nutlets”) under the soil. The tubers, or nuts, are grown on underground stems known as rhizomes that can grow as deep as 12 to 16 inches under the surface of the soil bed. Buds sprout on the tubers and grow new plants, this process eventually leads to a patch of Nutsedge.

nutsedge_shootsNutsedge looks similar to grass, but the blades are thicker and stiffer than most grasses. They grow straighter and in sets of 3 stems at the base (as opposed to 2 in grasses).

An infestation of Nutsedge is problematic because it grows twice as fast as turf grass requiring more frequent mowing and it is lighter green resulting in non-uniform turf appearance.

Fighting Nutsedge

Nutsedge is nearly impossible to get rid of, but it can be controlled. If you are lucky and catch the Nutsedge early you can limit the production of tubers, which will suppress it from spreading. To limit tuber production continually remove the shoots and as much of the plant as possible by hand every 2 weeks. This will cause the plant to put all of its energy into growing new shoots instead of new tubers. Mature tubers can re-grow their shoots up to 12 times, so you will need to be consistent.Nutsedge TubersSince Nutsedge looks similar to grass it is difficult to recognize early. If it has already taken over a small portion of your lawn you may want to consider chemical treatment. The best herbicide to treat Nutsedge is called Sedge Hammer, which is very expensive and can only be applied by a Certified Spray Technician (AZ SPCC Certified). The chemical should be applied during the growing season every 3 weeks; it will take as many as 3 or more applications to fully control the Nutsedge. To find a company with Certified Spray Technicians visit

Weeds Are Among Us

main-weed_imgSoaking rains bring much needed water to our desert environment, including plants. Rainwater is especially beneficial to plant material as rainwater is less alkaline than our irrigation water. While rain is a positive thing for our plants and irrigation water bills, it also helps weeds grow. For effective weed control in your yard, manual removal is the easiest way to get rid of a small number of weeds. To control weeds over a large area, herbicides are the most efficient tools available. There are two categories of herbicides for weed control: Pre-emergent and Post-emergent.

Pre-emergent herbicides:

Pre-emergent herbicides are designed to prevent seeds from germinating in the soil. They are most effective when applied during the rainy season. In Arizona, that means either before the summer monsoon in June & July and from October through January to take advantage of the winter rains. A timely application of pre-emergent can greatly reduce the number of weeds that germinate since it inhibits the weeds’ roots and does not allow them to grow.


Post-emergent for winter and spring weeds:

Post-emergent herbicides kill weeds that have germinated and are visible in the landscape. To kill weeds in winter months, you need to use a herbicide containing Diquat.

Spectracide products, which contain Diquat, are available for personal use at most home improvement stores or nurseries.

Post-emergent winter

Post-emergent for summer weeds:

Spring and summer are the best times to use Roundup concentrate. Be careful not to spray weed killer on plants or turf as the weed chemical is absorbed by the leaves and travels through the plant. These products cannot differentiate between plants and weeds. Additionally, this type of weed killer does not instantly kill the plant.  If you spray the weed and then remove it, any remaining roots may not have time to absorb the weed control spray.

Post-emergent summer

*Product label design and prices may vary. These products are Environmental Protection Agency (EPA) approved and have been deemed safe and reliable. No license is needed to apply most herbicides on your own property. DLC trains and maintains a crew of applicators to safely transport and apply these herbicides in your common areas. Our spray applicators are Licensed Pest Applicators by the State of Arizona Office of Pest Management. When dealing with any chemical, make sure to read the label and follow instructions carefully.


Caring for your Landscape: Fertilizing Ryegrass

Fertilizing Your Winter Lawn

Proper fertilization of your overseeded lawn is essential for healthy growth and good color during Arizona’s winter season. However, over-fertilization will increase your water bill and require more frequent mowing. The following tips will guide you on your way to a successful, and cost efficient, fertilization process.

Healthy Lawn After Fertilization

Fertilizing for Success

Ryegrass requires regular fertilization. During the winter months, apply a fertilizer, such as ammonium nitrate which is formulated for colder temperatures, to your lawn approximately every three to four weeks from November to February. The optimal time to fertilize your lawn is early in the morning when the dew is heavy. The dew causes you to leave tracks as you’re walking across the lawn and it’ll be easier to see where you’ve been. Also, there is less wind and the fertilizer is less likely to blow around. Always follow the directions on the package. Additionally, you may want to consider applying ferrous sulfate or iron chelates. These two products help keep grass green while reducing excess growth. All of the products mentioned above can be found at your local home improvement store or nursery.

A hand spreader is an essential tool for properly fertilizing your lawn.

Avoid Over-fertilization

When grass is over-fertilized, salt builds up and dries out the soil, eventually killing the grass. Often, we just put the fertilizer in the spreader and start. Resist the urge to skip over the package instructions. While having a plan in place and following a schedule can be helpful, nothing beats routine inspections. Regularly monitoring your lawn will help you pre-empt any issues that may arise due to over or under-fertilzation.

QUICK TIP FROM THE EXPERTS: If you notice the tips of grass blades turning brown, it is likely a sign of salt build up or over-fertilization. The best thing to do is to run a one-time extended irrigation cycle. This will help leach or push the salt buildup from over-fertilization down below the roots.


Caring For Your Landscape: Proper Watering During Overseed

Why Is Proper Watering Important?

Proper irrigation can conserve water, save you money and ensure a healthy, beautiful lawn come winter. Once you’ve applied the seed, the following tips will help you along the way.

Water You To Do??

  • DO inspect for system deficiencies. Prior to seeding, inspect your irrigation system for clogged nozzles and leaking or broken sprinklers.
  • DO setup 3-4 watering cycles per day. Applying too much water in one increment results in the ground reaching a saturation point, causing any additional water to run-off and be wasted.
  • DO make a check to avoid puddles. Always make sure the water from the previous cycle has been absorbed before starting the new watering cycle. If it hasn’t, reduce the run time for that zone.

Water You NOT To Do??

  • DO NOT overwater. Seedlings can tolerate being a bit on the dry side for a short period but will fail quickly if drowned.
  • DO NOT mow when the lawn is wet. (HINT: Turn the water off for a day before your first mow.)
  • DO NOT forget to pat yourself on the back for a job well done. By following these tips, you’ll surely have a beautiful lawn and cheaper water bill.

Overseed Water Schedule

Water Schedule 1 – Germination

Watering 3-4 cycles a day for 5-10 minutes is sufficient. Your goal is to keep the seed damp until it germinates which should take about 7 days.

Water Schedule 2 – Grass Reaches 1.5 to 2 Inches Tall

When your grass is about 1.5 inches tall, it’s ready for the first mow. Now is also the time to reduce watering to one cycle a day.

After the second or third mow, depending on temperature, wind, rain, and soil conditions, water every other week or as often as 2 to 3 times per

The Benefits of Not Overseeding

The Growing Season

header_turfDoes your warm-season, hybrid Bermuda grass look sparse or weak?  The culprit may be continuous overseeding. Often times, this is due to the competition for nutrients between the Bermuda grass and the perennial Ryegrass used in fall overseeding. Overseeding leaves the Bermuda needing recovery time to build strength and vitality before the next growing season.

Overseeding in the fall does not allow Bermuda grass to complete its normal growing cycle before winter dormancy approaches. Much like a bear preparing for hibernation, Bermuda spends the weeks and months prior to the cold season storing the reserves it needs to keep its roots and stems alive through the winter. Overseeding interrupts this process and often, die-back results in the root system. The effects of interrupting this process are seen in the spring when weather conditions are right for Bermuda to begin growing again. The thick, tall Ryegrass will keep the Bermuda shaded and cool, which prolongs the dormancy period.  By keeping the Bermuda dormant longer, the percentage of Bermuda that runs out of food before it can begin to photosynthesize increases.

When the Bermuda does come out of dormancy, it must contend with the Ryegrass for nutrients while the Ryegrass is at its strongest. Ryegrass is a fierce competitor for all the resources required for Bermuda to grow: sunlight, water, nutrients and even oxygen. During early spring, the Bermuda is at a disadvantage during the time it should be strengthening to withstand the extreme heat and dryness of a typical Arizona summer. By mid-summer, the Ryegrass dies out and physically impedes the Bermuda’s ability to spread. The dead Ryegrass must be removed through dethatching, which may further injure and set back the Bermuda. In most cases, the Bermuda does not get the time needed to recover because overseeding starts again in just a few weeks.

Bermuda Comparison

We recommend suspending the overseeding process for at least one season to help restore the root system and nutrients of the Bermuda grass.

During the Dormant Months

Not overseeding turf areas with winter Ryegrass changes the focus of your seasonal practices. The steps below will help you prepare for the next season of Bermuda grass during the winter:

•  Mow twice monthly to maintain a clean appearance and
even look

•  Control weeds

•  Top dress to fill in holes and areas of compaction

What to Expect

turfBermuda grass can stay green until the first frost, usually the middle of December. Around the middle to end of March, when nighttime temperatures begin to approach 60 degrees, Bermuda starts to grow again and returns to a regular mow and care cycle.  It should also be noted that by not overseeding there are significant savings that can be helpful to any household. Click the link for an article written by a Water Conservation Specialist, highlighting some of the additional benefits.

Estimated Cost Savings