In the world of turf, September is for winners!
It’s really annoying how we’ve been trained by the big manufacturers and retailers that our first springtime application of crabgrass preemergent is STEP 1.
STEP 1 should be in sync with the growth cycle of our cool season turf, which would be our first fall application of nitrogen.
NOW is the time to prepare for turfgrass renovation. Print this document off. Read it twice.
If you’re going to RENOVATE, which is starting from scratch, late August and September is the time to do it, because you need to kill off your existing lawn and weeds with Roundup®. It’s best if you start early enough to make two applications of Roundup, 3 to 4 weeks apart. If you’re going to OVERSEED, you want to be done by mid-October. Basically, you overseed decent turf, and you renovate crappy turf.
Typically, we start re-seeding in early to mid-September, because grass seed will germinate rapidly with warm soils. Cool nights help keep the soil uniformly moist. The fall weather will have a profound influence on success. You want to take advantage cool weather (85F day / <60F night) and moisture. But if it gets hot and humid after the turf germinates, apply propiconazole fungicide to protect those tender seedlings. You will need to irrigate lightly and often for the first 3 weeks, so don’t plan a vacation after you do this.
Why RENOVATE? If your lawn “sucks”, then it’s better to kill it off and start over. If you can see the soil on over 40% of the surface, your lawn sucks. Time to do something drastic. If your yard is mostly weeds…your lawn sucks. Kill it and start over. Or, at least spray Roundup on the weedy patches. Solid patches of turf that have survived need not be destroyed! That’s tough turf!
Why OVERSEED? Adding new and improved varieties into an existing turf sward will allow you to improve your turf, more slowly than renovation, but it’s less destructive. Coupled with core aeration, renovation can enhance quality tremendously. Core aeration literally pokes hundreds of thousands of holes in your soil. Those holes increase the oxygen supply to the roots, which is critical because of our heavy clay soils. In addition, the cores that are left on the soil surface actually dissolve down on top of “thatch.” That soil is loaded with a microbial population that is hungry for thatch. AND, the soil cores will actually crumble/smash down atop the seed that you’re spreading, helping that seed emerge faster. Covered seed comes up much faster than exposed seed.
Can you use a “dethatching machine”? You can use a “dethatcher” to work your lawn over. This is an old-fashioned machine that basically just beats the hell out of the turf. You need to set the spinning metal tines so that the only cut 1/8” deep groves in the soil. It works best if you scalp the grass first. CAUTION! Don’t scalp your turf in one pass—mow it successively shorter 2 to 3 days in a row. If you can set your mower at 1.5 inches, that’s scalping! Especially if you’ve been cutting at 3.0 to 3.5 inches all summer. Clean up the mess before you spread grass seed. Rake it and get rid of all that organic trash.
WARNING: this method is labor intensive (but usually worth it). Zoysiagrass swards benefit from this every 3 to 4 years or so but DO NOT AERATE OR DETHATCH ZOYSIA AFTER AUGUST! That’s best done in June or July. I recommend that you core aerate, versus using the dethatcher. Read on.
COMPLETE RENOVATION TIPS (For crappy lawns!):
1)Kill the lawn section with Roundup ASAP. Don’t mow before spraying! Roundup will work better with all the fresh, succulent tissues to absorb and translocate more herbicide to the roots. Don’t be a tight wad with the Roundup. Buy the concentrate and use 5 oz/gallon. Be sure you buy “plain” Roundup. Don’t use the “extended” control, “fast-acting” or poison ivy variants! Use a hose-end sprayer and be careful that you don’t create a lot of mist, which will float to your favorite ornamentals. Or your neighbor’s lawn—they’ll be pissed.
2)After four to seven days scalp the lawn with a mower. Call 811. It’s free and they want 3 days advance notice. You really want to cut the cable lines, especially your neighbors’ cable. Mark your own hazards, too, like irrigation heads and underground doggie-shock lines. Dog lines are usually deep enough to avoid damage, but that damn cable company usually only buries their cable one inch deep. If by chance your machinery cuts a cable line, don’t let them bully you into paying for repairs. They are supposed to put their cables ~6 inches deep…RIGHT!
3) WHAT TYPE OF GRASS SHOULD YOU USE? For non-irrigated, sunny swards, turf-type fescue is the best type of seed to use. About 35% of the swards in the transition zone will do best with this type of seed, especially for new subdivisions, lacking large shade trees. It is by far the best of the cool season species for full sun without irrigation. But, the best turf for deep shade is a blend of three very shade tolerant, fine-bladed fescues: meadow fescue, sheep’s fescue and creeping red fescue. If you haven’t had much luck growing turf-type fescue in non-irrigated shade, try a 3-way fine fescue mix. Another great blend of seed is a blend of turf-type fescue and a medium-green colored bluegrass. Bluegrass spreads laterally by rhizomes, thus it will help fill in the divots and holes caused by disease and moles. A pure bluegrass sward is a thing of beauty…but bluegrass is pretty tough to grow for most folks. If you don’t have an irrigation system, don’t even try it. Bluegrass doesn’t like FULL sun, and it doesn’t like deep shade, either. If you’ve got a yard that has 20 to 40 year old shade trees that provide up to 6 hours of shade in each “ecosystem,” you can probably grow bluegrass. The newer varieties are a hellofa lot tougher than they were just 15 years ago. If you’re not sure, go with Winning Colors Plus blend…turf-type PLUS bluegrass. The bluegrass will grow where it’s happy, and the turf-type fescue varieties will grow where they’re happiest. Talk about a win-win!
5) Get a soil test if you’re having problems growing grass in the shade! The proper pH (soil acidity), phosphorous and potassium levels may help you out…and most shady soils have acidic soil and low fertility. Those tree roots are competing for more than sun and water. Tree roots will scavenge all the P and K in the topsoil, causing low fertility.
6) After you scalp the lawn look and see how many new weeds have emerged within a week. More than likely you’re going to see how inept you were on your first pass at nuking the lawn – retreat with Roundup. If you see tiny weeds sprouting and green tissue all around, retreat the entire area. Trust me, it’s worth the extra time, energy and money spent to start with a weed free area.
7)Five days after the second application of Roundup, rent a “verti-slicer” or “slicer-seeder”. This machine cuts a grove into the soil, and then drops seed into the grove. Having good seed-to-soil contact will dramatically enhance germination and establishment. There is no need to set the blades any deeper than 1/8th inch deep!
8)If you can tend to all these tasks, and have the seed in the ground by mid-September, you will be rewarded with a fabulous lawn. It will be green and thin this fall, but lush and full by next May –- a real “award winning” situation. Try to be DONE by October 1st. You’ve get a 95% chance of success if you’re complete by this date. After October 15ththe odds of success diminish, depending upon the growing conditions in November. If turf can get established to the point that you have to mow weekly in November, you’re in great shape.
9) For OVERSEEDING use 4-5 lbs of turf-type fescue per 1,000 sq ft, 5 lbs of shade fescue blend, and 1.0 to 1.5 lbs/M of bluegrass.
OVERSEEDING TIPS (WHAT MOST OF YOU NEED TO DO):
1)New turf varieties are more disease and heat tolerant than older varieties. That’s why you should overseed every couple of years.
2)Cut your lawn successively lower from 3.5 inches down to 2 inches. Don’t do it all it once folks, because the resultant hay will interfere with your seeding. If you can bag, we recommend that you cut it every day, lowering the deck on the mower over 2 to 3 cuttings.
3)Rent a core aerator, which pulls a plug of soil, approximately ½” wide by 2 to 3” deep.
4)Get your BROADCAST SPREADER out of the garage (if you’re still using that rusted-out, nasty-ass old drop spreader, get rid of it), set the opening around ½ to 5/8th inches for turf type fescue, ¼ inch for bluegrass. Spread 25% of your total seed on the turf BEFORE you make your first pass with the aerator. You read that right—BEFORE your first pass. You want the cores to cover the seed more than you want the seed to drop into the holes. Concentrate on the really barren areas with the first pass of seed.
5)Make 1-2 passes with the aerator.
6)Spread another 25% of your seed.
7)Make another two passes with the aerator, perpendicular or diagonally to the first pass. All the plugs that you pull out of the ground are valuable! They’re covering up seed, in addition to providing more air to the grass roots.
8)Spread the last 50% of your seed. If you followed directions, you made at least two passes in good turf, and as many as 4 to 5 passes in your problem areas. All the seed that falls into the bored holes, and all the seed that ends up under a “melted” core, will germinate rapidly.
10)Leave the soil cores where they are – the microbes in the soil help break down the thatch. The bored holes enhance water penetration into your soil.
11) This method is the BEST, but if you’re short on time and labor, just aerate the crap out of the yard (as many times as you can), and follow it up with no less than 4 lbs/M of turf-type fescue seed. This method is perfectly suitable, and will save you a lot of time.
12) Crucial to your success is seeding at the right rate. For NEW SEEDING or RENOVATION with turf-type fescue and shade fescue use 10 lbs of seed per 1,000 sq ft, and 3 lbs bluegrass.
FERTILIZATION: If you know your ACTUAL SWARD SIZE, and you have a decent spreader, you can safely apply “regular” fertilizer, at a maximum of 1.0 lb of actual nitrogen per 1,000 sq ft. It need NOT be “starter fertilizer.” Starter formulations have lower nitrogen and higher phosphorous. Most of us have HIGH soil phosphorous anyway, thus any nitrogen is OK. If you can’t start till late September I recommend you still apply nitrogen to the lawn in late August to early September.
BAD SPOTS ALONG PAVED SURFACES: Seed won’t grow well if it’s just scattered atop the soil. For the really bad spots, we suggest you cover the seed with either PennMulch® or bagged topsoil. Avoid straw except for very large areas. Straw introduces a lot of weeds.
WATERING TIPS: Use frequent irrigation to get the seed up. The first couple of days after seeding you can water with your normal irrigation cycles. As soon as the seed comes up, though, you’ve got to sprinkle the turf babies with frequent, shallow irrigation. It’s critical that the top ½ inch of soil NOT dry out extensively. If you own an irrigation system, just run it 3X day with about 2 to 3 minutes per station. I can’t tell you exactly what to do for your own yard! You need to be observant. Don’t water so much that you turn the yard into a swamp, either. As the new grass gets taller, you go back to watering more deeply and less frequently. Within 3 weeks after the turf is up, you should be able to water every other day.
MOWING: Stay off the new grass while it is short and fuzzy. But when it gets to be about 2.5 inches tall, run the mower over it, cutting it around 2.0 to 2.5 inches. The turf can handle the foot traffic, but don’t rip it out of the soil with your mower tires. Slow and steady!
DON’T LET LEAVES PILE UP: Don’t let falling leaves cover up your newly seeded areas. While established turf can handle a once-per-week mowing, new turf should be leaf free most of the time. This is where a blower works wonders.
FUNGICIDE: When the new seedlings are one inch tall, apply propiconazole fungicide to provide a “health boost”. It will protect the seedlings from the key diseases that harm turf, especially if it’s hot and humid.