How To Open a Tennis Court?

New Hampshire tennis friend Nick Ourusoff is seeking advice on the best way to open a soft tennis court for the new season. He writes …

“I have almost finished raking the leaves and the grass is just beginning to be visible above the surface. I have my roller filled with water. I can discourage the grass a little if I roll a few times (do you think so?). I can spread MgCl2 (magnesium chloride) – will that help discourage new grass? And finally, after adding MgCl2 and new topsoil and putting down the lines, I can PLAY. I actually think playing is a good way to discourage new grass.

I could also use a chemical product, probably before I do anything else.
What should I use to kill the new grass as it tries to emerge?
I know you use “Roundup” to control grass at the Lake.
How friendly is it to the environment? To animals (dogs, cats)?

I will appreciate any thoughts you may have for my court at our summer home. Kind of an SOS! Thanks.”

Any court-opening veterans have advice for Nick on his court? (So I can play on it when I get up there!!!).

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6 thoughts on “How To Open a Tennis Court?

  1. I will leave it to others to address the main topic of how to open a clay court and confine my comment to the question about Roundup. (As an environmental attorney, I have some basis to comment.)

    Roundup is one of a bunch of EPA approved chemicals that all fall within a category of regulation called herbicides. EPA has jurisdiction over the use and safety of these products under a federal law called FIFRA. Other chemical products that are also subject to regulation under that law include rodenticides (e.g., rat poisoning), insecticides, fungicides, pesticides, etc. Pretty much all chemicals that are subject to regulation under this law are, or have the capacity to be, dangerous to some degree. The purpose of the regulations is to assure that these products are handled and used safely, or as safely as may be possible. As a result, some products are not allowed to be sold to or used by non-certified persons at all but some, like Roundup, are allowed to be purchased and used by consumers.

    The key to all of these products is that they must NOT be used in any manner or for any purpose inconsistent with their labels. In fact, it is a violation of federal law if they are used inconsistently with their labels, but for technical legal reasons not necessary to get into here, there are exceptions to that rule for ultimate consumers. Suffice it to say, to be both safe and to be legal, make sure you closely follow ALL instructions for use of these products on their labels.

    One of the biggest problems that exists is that, often, the labels are very detailed, very long, and frankly quite confusing. They are also sometimes hard to peel off the containers (they usually are several pages long) and prone to getting lost when you do get them off. So, a trick that helps is to be aware that you can always search for more readable copies of the labels on the internet. Every manufacturer of such a product will have a copy of its most up to date label available this way. If you print them out from there, they are much easier to read. (But be aware that there are differences between the FIFRA labels themselves and things called MSD (material safety data) sheets. The latter are federally mandated for other reasons and under another law. They do not provide nearly as much information as the FIFRA labels do. You need to download the FIFRA labels and not the MSDS information.)

    Another thing to be aware of – and this is why following the labels closely is so important – is that the toxicity of these chemicals can be lessened by proper application, but can also be increased by improper application. So, if the label says use gloves and a breathing mask to apply, then do so. What this means is the chemical can enter the human body through both dermatological contact or by breathing in vapors, and you need to avoid that. If the label says use eye protection, then do that as well. It means the chemical could be caustic to sensitive areas like the eyes and/or it could also be absorbed into the body by that means. If the label says to dilute with water in a certain ratio, then do that as well. It means the chemical was tested and approved at that concentration and is too powerful if used right in the container. And if the label says do not apply the chemical to certain surfaces or in certain locations (like Roundup says, I believe, do not use near vegetable gardens or on grass), then follow those instructions.

    Of all of the herbicides, Roundup has been shown to cause the least, or close to the least, amount of problems. But that does not mean it is 100% safe to use in every situation. It only means that, based on the studies that were in existence when it was approved for usage by the EPA, the agency found its degree of risk to be low enough that it could be managed and made acceptable by the conditions set forth in the label. In short, you would not want to drink the stuff. Similarly be careful — VERY careful — that you follow the instructions about letting your pets, kids or grandkids walk or play in any areas where the product has been put down. There are instructions on the label about this as well, I believe, including a minimum wait period following which it is presumed safe to allow your dog to walk in an area that has been treated, for example.

    Finally, recognize that just because a product has been approved by the EPA in the past as safe, or safe if used with XYZ conditions, this does not mean the analysis is over. Products like Roundup are constantly being retested to make sure the science continues to support that they are safe — much the same that prescription drugs are also subject to this. Over time, this may mean that health and safety risks that were not originally apparent or established may be shown to exist by better or more comprehensive studies.

    There have been recent news reports that a peer reviewed study has either now shown, or at least suggested the possibility, that heavy use of Roundup could contribute to diseases like Parkinson’s, infertility and certain cancers.
    See This may, or may not, be the last word on this topic – it is clearly beyond my own expertise – but it is certainly something that I would consider in whether to use an herbicide at all on something like a tennis court. Weighing the options, I would probably ask myself whether the grass and weeds could not be just dug up as opposed to zapped with an herbicide, balancing the risks associated with the herbicide against the convenience and reduction in work.

    I hope this helps.

  2. Nick,
    You might try calcium chloride to retain moisture at the surface and discourage weeds. I suspect it will be less expensive (~$15/50#bag at RP’s) than magnesium chloride.
    Bud rice

  3. Weeds: After the court is open every year I spread a generous layer of Preem with a brodcast spreader. Do the whole court not just the playing area. I use at least four or five large sizes. Cost over $100.00 but a lot less work weeding for me. I just let it work itself into the court during the first week or two of play. It does not bother the play though it may look like it would. My dogs seem to be OK with this. Since I started this I have had a lot less weed issues. More play also leads to less weeds and grass.
    Rolling: My best results with the Har Tru court has been rolling with my roller dry (I don’t add water to the roller) and rolling as often as I can after rain. I overlap my rolling. You want to find the right weight for your roller and court. Don’t roll until the surface water has drained. If the roller picks up the Har Tru stop and let it dry more. I like the court firm so you don’t dig it up playing but not like concrete.
    This is what has worked for me.

  4. Thanks very much for your comments, Marty, Bud and Rich. Marty – excellent advice, very much appreciate your detailed analysis. Yes, I have heard that Roundup is cancerous and that you do need to be careful. Bud, I’ll try calcium chloride (I have used it in the past, recently magnesium chloride is what has been delivered as “salt” for our court).) Rich, I will investigate Preem – it has been recommended as something to look into by an ecologically sensitive landscaper friend. And George – m,any thanks for putting it out there on you bLOg!

  5. Nick,
    One more thought: There’s something useful to read. Michael R. Humphrey, who has a Summa Cum Laude BS in Plant and Soil Science and is (or was, I haven’t seen him in years) the groundskeeper at Longwood near Boston, wrote “A manual of Clay Tennis Court Maintenance”. It is 70 pages and worthwhile, if still in print.

  6. I am investigating 2 other intersting options: (1) use of hortocultural grade vinegar (20% acidic). A representative of Chippers, a regional horticultural compnay recommended to me by an ecologically-minded landscaper, will be looking at our court and giving me a quote – but what I want is advice; (2) if one covers the court with a tarp or black plastic and deprives the grass of sunlight, everything living will die in 2 months. I plan to do this in the Fall, using bricks to keep the tarps(s) or plastic in place.

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