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chitra0828_gw

Re-seeding a new lawn. Help!

chitra0828
9 years ago

We installed a new lawn this Spring (had no choice with the timing as this was a brand new home). We had the lawn hydroseeded in April and have irrigated it regularly since. We got some very good advice on fertilization and weed control from the helpful folks on this site and based on that, held back from applying any fertilizer or weed control until late summer/early Fall � which is of course now.

We have hired someone to apply fertilizer and weed control (he is using Q4, which from my basic research seems to be a reasonable choice to kill weeds, but not our fledgling lawn). Then in a couple of weeks, we plan to aerate and overseed. Some questions:

1. Is aeration necessary and recommended? When the house was completed in spring, we had several inches of top soil put down and compacted, and have been advised that aeration will definitely help.

2. Is around mid Sep a good time to overseed? We are in southwest CT.

3. What mix of grass seed would you recommend? The original lawn was a mix of Rye Seed and Kentucky Blue Grass, but we definitely lost some seed due to torrential spring rain, so I am not sure what exact mix actually germinated. I suspect there was more Rye than KBG. I understand that Rye and KBG are decent choices for Fairfield County, Connecticut, but also Tall Fescue or Fine Fescue are also good and potentially more heat/cold resistant. Does it make sense to go with a mix of all these?

4. Our lawn area is ~18000 sq feet. The lawn is ~3 inches high and reasonable overall, with a few sparse patches. How much seed should we need for overseeding? A quick web search suggested 4lb/sq foot for Tall Fescue and Perennial Rye and 1-2lb/sq foot for KBG. Does this sound reasonable?

Thx All! Chitra

Comments (10)

  • yardtractor1
    9 years ago
    last modified: 9 years ago

    1. Is aeration necessary and recommended? When the house was completed in spring, we had several inches of top soil put down and compacted, and have been advised that aeration will definitely help.

    Aeration can be used to cure compacted soils. On new construction with trucked-in topsoil, unless construction equipment was regularly driven over it while the soil was wet, you do not have compacted soil. Aeration can also be employed to quickly amend the soil if there are deficiencies. A soil test would identify any deficiencies and determine if aeration would aid in adjustment. With the information you have given, aeration is not advised.

    2. Is around mid Sep a good time to overseed? We are in southwest CT.

    Now is the time to plant KBG. It can take 4 weeks to germinate and another couple of weeks to grow tall enough for mowing and to harden off to better survive winter.

    3. What mix of grass seed would you recommend? The original lawn was a mix of Rye Seed and Kentucky Blue Grass, but we definitely lost some seed due to torrential spring rain, so I am not sure what exact mix actually germinated. I suspect there was more Rye than KBG. I understand that Rye and KBG are decent choices for Fairfield County, Connecticut, but also Tall Fescue or Fine Fescue are also good and potentially more heat/cold resistant. Does it make sense to go with a mix of all these?

    KBG actually has better cold resistance. Heat resistance is debatable. I prefer KBG's characteristics. (appearance, disease, cold, and heat survival abilities)

    4. Our lawn area is ~18000 sq feet. The lawn is ~3 inches high and reasonable overall, with a few sparse patches. How much seed should we need for overseeding? A quick web search suggested 4lb/sq foot for Tall Fescue and Perennial Rye and and 1-2lb/sq foot for KBG. Does this sound reasonable?

    Those rates are reasonable, but it's per thousand sq feet, not per sq ft. The diference in recommended wight is due to the difference in siae of the seed. Rye and fescue seeds are larger than KBG seeds, so 1 lb of KBG seed will contain many more individual seeds than 1 lb of fescue.

  • chitra0828
    Original Author
    9 years ago
    last modified: 9 years ago

    Yardtractor ��" thanks for your responses. A few points/questions:

    1. On aeration, we have had a few landscapers come out, and they all say the soil is compacted enough to require aeration. That said, if we don't do aeration, how would you recommend putting down the seed? I assume we wouldn't just drop the seed on the existing lawn?

    2. We just had a weed control and fertilizer application put down yesterday. So I am assuming we would need to wait a couple of weeks before we do the overseeding? Is mid Sep soon enough for a mix of Rye and KBG?

    3. Thanks for the comparative comments. Any thoughts on Tall and Fine Fescue? Our original seeding as it turns out was a mix of KBG, Perennial Rye and Fine Fescue (roughly 1/3 each).

    4. Yes typo on my part ��" I meant lb per 1000 sqft of course (otherwise that would be one heck of a seed bill!) Are there any commercially available mix of seeds that you know of that could work?

  • yardtractor1
    9 years ago
    last modified: 9 years ago

    1. On aeration, we have had a few landscapers come out, and they all say the soil is compacted enough to require aeration. That said, if we don't do aeration, how would you recommend putting down the seed? I assume we wouldn't just drop the seed on the existing lawn?

    Again, from what info you have given, it is unlikely you have compacted soil. For aeration to be a truly successful remedy of compaction, it should result in a minimum of 20 holes per sq ft. and at depths 4" or greater. I know of no landscaper that has that type of equipment--the type golf courses have. As aeration is messy and expensive, I only use it when I can combine it with other processes like topdressing, adding gypsum, fertilizing, etc. Seeding is not one of those processes. Although seed does seem to germinate well on the aeration hole edges, the seeds that fall into the deep holes do not and are wasted. Seed does germinate better when the soil surface is broken, but many have very good results just seeding over bare ground followed by rolling or a thin layer of peat moss. If your bare spots are not too large or numerous, light raking of the soil is fine. I get best results with KBG by broadcasting seed and then running a slit seeder over it. Just dropping seed over the existing lawn is common and called overseeding.

    2. We just had a weed control and fertilizer application put down yesterday. So I am assuming we would need to wait a couple of weeks before we do the overseeding? Is mid Sep soon enough for a mix of Rye and KBG?

    I have not used Q4 specifically. Weed B Gone Max contains a similar AI cocktail as Q4 and Ortho recommends that overseeding not be done sooner than 4 weeks after application. As far as seeding is concerned: late summer is preferred as temperatures are beginning to subside, weed pressure is at a minimum and torrential rains are less common. Temps that do not fall below 50 F at night and that rarely exceed 80 F during the day are ideal for cool season grass establishment. No weed pressure removes the problems of feeding and watering the turf without feeding and watering a crop of competing weeds. Cool season grasses need to be planted early enough before soil temperatures fall below 50-55F--when grass plant growth slows or stops-- so that there is enough time for germination and subsequent plant growth so a root system develops and top growth has the chance to harden off--usually about the time of the third mowing. This time frame is dependent on region and the whims of Mother Nature--there is no hard and fast rule.

    3. Thanks for the comparative comments. Any thoughts on Tall and Fine Fescue? Our original seeding as it turns out was a mix of KBG, Perennial Rye and Fine Fescue (roughly 1/3 each).

    Lol. Yes I have "thoughts", but they are just my opinion. All cool season grasses have advantages and disadvantages. Fine fescue is one of the few grasses that will grow in shadier areas, but does not hold up well in traffic. Rye and TTTF can make nice lawns, but they do not spread and self repair and require occasional overseeding to maintain thickness. My preference is KBG. If you can grow KBG, that is my recommendation. It makes a beautiful blanket lawn and after the third year, it is self repairing. I wont list the reasons I find it superior, but they are many, but choice of turf is subjective in many ways.

    4. Yes typo on my part ��" I meant lb per 1000 sqft of course (otherwise that would be one heck of a seed bill!) Are there any commercially available mix of seeds that you know of that could work?

    I thought it was a typo, but better safe than sorry.
    You could check NTEP for the individual turf grass names in commercial bags to see what each type's individual characteristics are. What you definitely want is a bag labeled as containing 0% weeds. Better yet, 0% other crop seeds.

  • beckyinrichmond
    9 years ago
    last modified: 9 years ago

    Since you need to wait four weeks before seeding, it will be probably too late for you to sow KBG. Maybe try a seed that germinates quickly. Tall fescue takes just a week or two. KBG takes up to four weeks to germinate. Or you could try dormant seeding over the winter if you'd like to go with KBG.

  • chitra0828
    Original Author
    9 years ago
    last modified: 9 years ago

    OK, we did some research and talked with our landscaper at length. A few things:

    1. I called the manufacturer of Q4 (PBI Gordon Corp) and spoke with someone in their Research department. He said the 4 week waiting time before seeding is a conservative guideline adopted when they first started selling the product. They now hold that 1.5-2 weeks is sufficient and are applying to the EPA to change their label.

    2. The lawn was sprayed and fertilized on Aug 25, and our landscaper is coming this Thu Sep 4 to assess its progress. Depending on how effective the weed control has been, he plans to do some spot spraying of remaining weeds (he is not charging us extra for this re-spraying).

    3. Based on the advice on Q4, we planned to overseed on Mon Sep 15, 10 days after the spot spraying with a mix of KBG and Perennial Rye.

    4. Our landscaper still believes aeration would be beneficial. His rationale is when he took a soil sample, he could only get down 2 inches due to the compaction. But he made clear this was just his opinion - he wasn't hard-pushing aeration.

    5. He has quoted $150-170 to overseed the lawn area (~18,000 sq feet) with 3-4lb/1000 sq feet with raking to disturb the soil surface. I thought this sounded like a reasonable price - any thoughts on this?

    Would appreciate any further thoughts on this gameplan.

  • beckyinrichmond
    9 years ago
    last modified: 9 years ago

    What's more important: getting rid of the remaining weeds with this particular weedkiller or getting grass established before frost? Glysophate could be used for spotspraying and you could plant immediately (glysophate will kill everything it is sprayed on so there will be some grass kill too). You should allow at least 6 weeks before frost when planting KBG.

  • chitra0828
    Original Author
    9 years ago
    last modified: 9 years ago

    Update here: our landscaper put down seed on Friday (a mix of Perennial Rye and Bluegrass). A few questions:

    1. He does not appear to have raked the soil, but just thrown the seed down on the existing lawn in the bare areas. Is this sufficient? Since I paid him for the job and specifically asked that he rake and disturb the surface, I am surprised he didn't do this.

    2. He did not put hay on the seeded areas. Is this necessary or desirable?

    3. Rather than hay, is it better that we put down compost? We called around a few local shops and nobody seems to stock compost. One shop does have cow manure, but it is wet and I am not sure how to apply that. Could you advise please?

    4. The landscaper did not put a starter fertilizer down, because he had applied a fertilizer when he applied the weed control on Aug 25. He said the fertilizer would last from 6-8 weeks, so fertilizer was not required until Oct 10 or so, which would be the late fall application to carry the lawn through the winter. This seemed to make sense to me, but wanted to check with you all.

    5. We are getting different opinions on how frequently to water. The temperature is now in 70s daytime and mid 50s at night. The landscaper thought every other day for 20 mins should be sufficient. Another guy who is helping us with landscape design said every day for 20 mins. Thoughts on this pls?

  • morpheuspa (6B/7A, E. PA)
    9 years ago
    last modified: 9 years ago

    1) Technically, yes. Good seed-soil contact is important, so if he did nothing, I might be tempted to go walk on the area, making sure to foot-print the seed into the soil. In larger areas, roll it.

    2) I hate hay. It hangs around forever, and usually contains weed seeds so...

    3) ...I prefer compost or peat moss. I used 1/8" of peat on my renovation to hold a bit of water. Topdressing isn't strictly required, but if you're going to use it (and it does help mulch the soil a little), either compost or peat moss is great.

    4) This is close enough to correct. Starter's phosphorus may not even be required (on my soil, it wouldn't be) and adding nitrogen at seeding time is a waste. Feeding around October 20th is approximately correct.

    5) None of the above. Twice per day to assure that the seed never goes dry (minimum; many of us do 3 or 4 times per day). Seed, left dry for 24 hours, starts to die, and losses mount very, very quickly. It's always better to have things a lot too damp than a little too dry.

  • chitra0828
    Original Author
    9 years ago
    last modified: 9 years ago

    Thanks very much morpheuspa - very helpful.

    On #3, as I mentioned, I haven't been able to find a shop selling compost. But one shop does sell cow manure - but given it is wet, how would we apply this?

    On the watering, if we do twice a day, how many minutes do you recommend per watering?

    This post was edited by chitra0828 on Sun, Sep 14, 14 at 16:37

  • morpheuspa (6B/7A, E. PA)
    9 years ago
    last modified: 9 years ago

    >>On #3, as I mentioned, I haven't been able to find a shop selling compost. But one shop does sell cow manure - but given it is wet, how would we apply this?

    I wouldn't use it. Raw cow manure (I presume this is what he means) is very high in soluble nitrogen and it's going to set off a bacterial and fungal explosion in the newly-seeded soil--just when the new sprouts are least disease resistant. Tiny amounts used judiciously in the mature garden are great, but not here and not now.

    If you can't locate good old peat moss bales, just go without it. You don't require a top dressing and millions of lawns come in beautifully without it.

    >>On the watering, if we do twice a day, how many minutes do you recommend per watering?

    It depends on the output of your sprinklers. Most rotary impulse sprinklers, on half circle, should run for about 15 minutes. Higher output sprayers can get away with less time but cover less area proportionately.

    A tripod rotary set full circle and at maximum distance would probably require 45 minutes per area...but would be covering 5,000 square feet at a time.