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hd28cat

Lawn fertilizer on my roses

hd28cat
15 years ago

Hi, my lawn care service came today and treated the lawn with a granular fertilizer. It looks like he got it all over my knock outs. Is this going to be a problem? If yes is there anything I can do to help?

Comments (19)

  • hd28cat
    Original Author
    15 years ago

    Thanks Kate. It was not weed and feed, just a high nitrogen granular lawn fertilizer. I am pretty new to gardening but I thought I had read that high nitrogen would cause lots of green and no blooms

  • littlesmokie
    15 years ago

    Can you ask the company what the product was & its NPK? (Is it made of chemicals that could burn or slower release organics like cottonseed/feather meals, alfalfa etc.?)

    Someone much more knowledgeable than I (michaelg, I believe) did a long series of posts on fertilizer here several years ago citing research that found that contrary to old school popular opinion, the best fertilizer ratio for roses is a higher nitrogen formula, something equivalent to a ratio of 3-1-2, or even 4-1-2. (For example, the pink label osmocote has this. It's a great time-release fertilizer that I use for my potted roses.)

    I have used one of these granular organic "lawn" (higher nitrogen) fertilizer deliberately on my roses. But, if your company used a synthetic, "turbo" nitrogen kind of formula, then I would be afraid that it might burn your roses, in which case I suggest water, water, water.

    Dawn

  • wirosarian_z4b_WI
    15 years ago

    As long as the lawn fertilizer does NOT have a weed killer in it you should be OK, just water them well like Dawn suggests. I use a high N (27-28%) lawn fertilizer for my 1st spring feeding on those roses that die back to the crown in my Z4 garden. Yes N promotes green growth but when all you have to start with is less tha 6" tall, you need to grow green growth before you can get any flowers. For my later season feedings, I switch back to something more balanced.

  • karl_bapst_rosenut
    15 years ago

    I learned long time ago that roses can't read. They don't care where the nutrients come from.
    I had 6 bags of lawn fertilizer with grub control stored in a shed for a few years. To use it up I put it on my rose beds. The roses seemed to like it. At least they didn't complain

  • hd28cat
    Original Author
    15 years ago

    Thank you all for helping. The only thing i can really tell from the 'bill' they left on my door is that it says 18-0-5 2.7% Mesa .09% Demension. My guess is that it is a synthetic. Lots of little white balls.

    I am very new to gardening. So Im not real sure about how fertilizing works but it seems to me that adding bone meal that is say 0-20-0 to what is already there would then add up to 18-20-5? Wouldn't that be better than not doing anything? Or would that overwhelm the plants?
    I just would hate to not have blooms. I have worked really hard on this project for the past three seasons and was looking forward to big rewards this year.

    One other thing, they also applied it all around several other flowering shrubs that I have. Several different viburnums and hydrangeas. I assume all this advice here about the roses would apply to them as well?

    My wife is telling me Im freaking out about nothing, it will all be fine. i hope she is right

  • hd28cat
    Original Author
    15 years ago

    OH Boy, OK I got the card out that he left and I was wrong. What he put down in the area where the shrubs/roses are was 45-0-0!

    The 18-0-5 was fertilizer and pre-emergent that he put on a different part of the lawn. (I have new grass seed down near the shrubs which is why he did not put any pre-emergent near them)

    So now we are looking at 45-0-0 on the roses. Slow release granular. Sorry for all the confusion. Should I just get the sprinkler out and let her rip all day tomorrow?

  • buzzsaw8
    15 years ago

    If it's slow release, you can try to water it in, but it probably won't do much good. It's coated.

    And that said, it's probably good that it's slow release rather than something like urea, which is a lawn fertilizer that is immediately available and would probably burn the heck out of the roses. Just don't add any fert. with N for a few months. Bone meal (high in P) and greensand (high in K) would be a good idea.

    Your roses will be fine. But do mention to the gardeners to be more careful next time.

  • lou_spicewood_tx
    15 years ago

    I'd bet it's very fast release urea type. You hired TruGreen right?

  • hd28cat
    Original Author
    15 years ago

    Actually Its a local company here in Louisville with a fairly good reputation. Farison Lawn Care and Sports Turf

  • lou_spicewood_tx
    15 years ago

    46-0-0 is straight urea fertilizer. Very fast acting. 39-0-0 (by Lesco) is 100% slow release urea so I'm not sure about 45-0-0. Is that what it says on your invoice? Ask them and find out for sure though. I've seen Trugreen use fertilizer that seems to act very fast for immediate greening effect but they fizzled out later on. The homeowners could not keep up with mowing and keeping grass(bermuda) out of plant beds. I suppose any business is better than Trugreen, at least with decent BBB rating. It's scary when you google trugreen for complaints. So many complaints...

  • karl_bapst_rosenut
    15 years ago

    I have, on occasion, thinly spread 45-0-0 on my rose beds.The type I used was a slow release but not that slow.
    In the amounts they put down, I doubt it was too much.

  • hoovb zone 9 sunset 23
    15 years ago

    Like others have said if there was no weed killer in there, the roses should be happy. I hit mine with 45-0-0 now and then and they love it. They get big. You might just want to make sure they're well watered, as a precaution.

  • mike_rivers
    15 years ago

    I agree that 46-0-0 is probably a straight urea fertilizer. No big deal, lots of fertilizers designed for roses get their nitrogen from urea. Miracle-Gro for roses, for example, is roughly 50% urea. The label recommends 1 tbs of Miracle-Gro per rose, every 7 to 14 days. That means that 1/2 tablespoon of straight urea per rose will provide about the same amount of nitrogen and, in spite of its "high nitrogen" analysis, will have no greater tendency to harm your roses.

    About excess nitrogen causing "lots of green and no bloom": There are plants for which excess nitrogen will produce vegetative growth at the expense of flower production. I do not think roses are among those plants. Consider the follwing quote from the Journal of Agriculture, 2000, 134, pages 421-425:

    "In contrast to other crops, roses do not experience antagonism between vegetative growth snd production. The improvement of vegetative growth implies higher flower production; each shoot will develop a flower."

  • dan_keil_cr Keil
    15 years ago

    I use Miracle Gro for Lawns wich is a 36-0-0 I have a lot of phophorus and potash in my soil. So all I have to add is nitrogen. My plants are 6' tall and blooming their heads off by the first week of June! My ph is 6.5

  • roseman
    15 years ago

    What's your soil temp? Many fertilizers don't work until the soil is of a specific temperature. Also, be sure what went down was not a weed and feed product. If it was, water the roses heavily to try and flush it away. Tell your lawn service to be more careful next time. They don't often know anything about roses. However, if the material was not weed and feed, don't worry too much. Roses are heavy feeders during the season and don't care what they get to eat every month as long as they get something.

  • gardenfanatic2003
    14 years ago

    If it was that fast releasing, it would burn the grass. It'll probably be okay.

    Deanna

  • gardenfanatic2003
    14 years ago

    I just noticed the date on the original post. Oops!

    hd28cat, so how did it turn out with the Knockouts and the lawn fertilizer?

    Deanna

  • roseman
    14 years ago

    As long as they didn't put down weed and feed, you should be fine. However, I would make sure they were aware of that for the future.