Over-seeding Tips for Homeowners

Over-seeding in the Fall in Arizona is a bit more complicated than scalping the Bermuda and then tossing on some rye grass seed but, not to worry, I will try and explain as much as possible all of the ins and outs of this process.  It is required that all Markwood North residents over-seed their front yards, if they have grass.

Seed:

The first things to consider are the various cultivars of grass seed available.

DO NOT use annual rye. It is an ugly yellow green grass with large fast growing leaves.

While the predominant seed used in Arizona is rye, one must consider which variety of rye to use, as well as, other options under various circumstances, such as shady areas.

Always use a blend of two or more perennial rye varieties in sunny areas. Using a blend lessens the possibility that a disease will kill all of the turf should one occur. Also this gives you various strengths to offset each varieties weaknesses. I prefer a blend of dwarf turf type rye grasses, which grow shorter than typical rye.

In the shade you should add to your rye blend a few of the following:

Poa Trivialis            bluegrass

Poa Supina            bluegrass

Creeping Red         fescue

Sheep’s            fescue

Hard                fescue

Preparation:

Around the first of September, you should begin cutting back on your irrigation to the turf. Reduce your watering days to once a week and allow the Bermuda to begin going dormant.

This will reduce the overall stress to the Bermuda grass and significantly cut down on the amount of debris produced during scalping.

Anticipate scalping/seeding around the first of October, weather depending. You should wait until nighttime temperatures are consistently in the 70′s.

A few days before scalping, flag the locations of all of your sprinkler heads and verify their correct operation.

Scalping:

Mow the turf down to your mowers lowest setting. Remove as much debris as possible. Trim along all obstructions and edges to the dirt.

Seeding Rates:

When combining cultivars, you should account for the total amount of seed in the combination. Example: 50% Rye with 50% Fescue – for a total 10 lbs./100 sq ft of seed or…Example: 90% Rye with 10% Bluegrass – Rye 6 lbs/1000 sq ft and Bluegrass ½ lbs/1000 sq ft for a total of 6.5 pounds of seed.

Just Rye – Apply 10 pounds of seed per 1000 Sq. Ft. of turf area.

Just Fescue – Apply 10 pounds of seed per 1000 Sq. Ft. of turf area.

Just Bluegrass – Apply 1.0 pound of seed per 1000 Sq. Ft. of turf area.

Incorporate the seed into the soil by raking.

Watering:

Pop-up heads, set for 4 minutes per cycle.

Center rotary heads, set for 16 minutes per cycle.

Edge rotary heads, set for 8 minutes per cycle.

The above times are averages; your times may differ based on flow and pressure. Gauge your output on each type of head by placing a jar or bowl ½ the distance of throw and recording the amount of water applied in a given period of time. Ideally you want about 1/8 inch of water applied each cycle

Set your irrigation clock to water 6 times per day, every day of the week. You may have to use more than one program. Start times should be as follows:

8:00     AM

11:00    AM

2:00     PM

5:00     PM

8:00     PM

11:00     PM

Two weeks after significant germination takes place, add time to the cycles and use fewer start times. Continue to adjust the cycles and start times until you have achieved a schedule of 1 watering per day, 3 days per week with approximately 1 inch of water being applied per watering.

Once the winter rains begin and if the temperatures are especially cool, you may only have to water once per week to maintain the turf.

If you reduce the watering schedule and wonder if there is enough water being applied to the turf… Look for a bluish discoloration, which will indicate the turf needs water, and increase the watering days.

Your remaining start time should be approximately set for 3:00 AM.

Mowing:

Mow the first time to 2 inches when the new turf has reached a general height of 3 inches.

Keep your blades sharp and if you desire a lower mow height, slowly lower the mow height by ¼ inch each week until you reach the height you want.

Do not mow winter turf grasses below 1 inch.

Fertilization:

Fertilize with a balanced fertilizer (21-7-14) immediately after your first mowing. These fertilizers are typically an ammonium nitrate product.

When daytime temperatures are consistently below 65 degrees, you must fertilize with a calcium nitrate product typically (15-0-0).

Ammonium nitrate products do not degrade properly in cool temperatures.