Garden Plot: More tips on grass and garlic

Which warm season grass is better – Zoysia or Bermuda?

Bob in Germantown writes: “Your recent bits on ‘TOP suggest that we may be better off switching to summer grasses in the long run. I grew up with Zoysia, but am not really familiar with Bermuda. Any recommendations?”

Each has its plus and minuses, Bob. Both are warm season grasses that are planted in the spring, go tan and dormant over the winter, thrive in the summer (when we use our lawns the most and when cool-season grasses generally die off) and are almost always free of weed problems and bare spots.

Unless you plant the starter plugs densely, Zoysia typically takes a couple seasons to fully establish, while Bermuda starts (seed) planted in the spring will fully cover the intended area edge-to-edge by the end of summer. Bermuda is one of the only warm season grasses that can be installed via seed – the other types are all installed vegetatively, using sprigs, plugs or sod.

Both are running grasses that require good edging to keep them inside their intended area, with Bermuda being the much more aggressive runner of the two. In fact, it’s so aggressive that Bermuda is best planted where lawns end at sidewalks or driveways – not adjacent to flower beds.

That big pest, moss

Raelene in Fairfax writes: “We are well into the second year of getting our lawn off drugs. The back yard has always been plagued with some shady spots, so we trimmed the trees. Now we’re wondering the best way to rid the lawn of an extensive moss problem.”

Well, first, congratulations on going natural. As Groucho used to say, the only difference you’ll notice is the improvement.

Moss thrives in damp, shady spots whose soil is extremely acidic. It can’t survive in normal pH levels. So, if the area now gets a solid four hours of sun a day, test the soil and then spread enough lime (or even better, hardwood ash from a fireplace or woodstove) to bring the pH number up to 6.5 or 7, and then overseed with a shade-loving fescue in mid-August.

But if it gets less sun than that, moss would be the groundcover of choice.

Brown patches in lawn? Too much chemical fertilizer

Dennis in Alexandria writes: “I’m starting to see small but growing brown spots scattered in the lawn. The root system is strong and intact and there are no signs of spots on the grass blades. I keep the lawn height at three inches using a mower with sharp blades and have [a lawn care company] taking care of the feeding and weed control.”

Well, Dennis, the company you named in your email is truly famous for gross overfeeding of lawns. That, plus the time of year and your excellent reportage tells me you have either “brown patch” or “summer patch” – diseases famous for preying on lawns weakened by overuse of cheap, quick-release chemical nitrogen fertilizers.

Don’t allow any more feedings until fall, when I hope you’ll take the turn and go all natural. And no matter what you use, cool season lawns in our area should only be fed twice – lightly in the spring and a big feeding in the fall. Summer feedings kill the grass outright, and multiple feedings beyond the two invite these patches and other disease issues to appear – and of course, contribute greatly to the continued degradation of the bay.

And, yes, that means that the constant radio spots during Major League Baseball games featuring the guy with the really bad Scottish accent imploring you to “Feed your lawn! Feed it!” are a Major League disgrace – and, at this time of year, technically illegal in areas with restrictions on lawn feedings.

Deter deer with eggs gone bad

Mary Lou in Woodbridge writes: “We live in a moderately wooded area whose resident deer population has discovered my hosta and daylily salad bar! Is there a commercial or home-made repellent that can be effective in deterring feasting deer? I saw one that said it was made from coyote urine.”

I really urge people not to buy so-called “predator urines,” Mary Lou. There’s no evidence that they work, and the collection of the “active ingredient” is incredibly cruel.

Now, the deer repellants that score the highest in university studies are commercial sprays made with putrescent egg solids (please don’t try to make this at home, you’d have to burn the kitchen to the ground afterward). We don’t smell the sulfur odor after the repellant dries on the plants, but deer do — and if they try and eat anyway, they give up after a nibble. Provided, of course, that you keep a fresh coat on the plants. That means spraying every two weeks or so and after heavy rains.

Look for a commercially-made repellant with “putrescent egg solids” as an active ingredient. There are many brands out there so pick the one with the highest concentration.

No scapes on garlic? You big softneck

Nelson in Arlington writes: “The garlic I planted last fall appears to be doing very well, but I see no sign of the “scapes” you mentioned last week on WTOP. One leaf on each stalk is starting to turn brown and I’d like to harvest it because I need the space for other vegetables. I don’t know what variety it is. I just broke apart a fat, healthy looking bulb from the grocery store and planted the cloves.”

Do not harvest it yet, Nelson. It’s not quite ready, and you’d be seizing defeat from the jaws of victory. The fact that it didn’t produce those distinctive bulges up top (the garlic “scape”) tells me that it’s a softneck variety – the white, “California” garlic that’s sold in most grocery stores. Not my favorite kind, but still perfectly good garlic.

But hardneck or softneck, you must wait to harvest until one-third of each plant has turned brown to get good sized garlic bulbs – which should happen toward the end of this month or the first week of July.

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