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Super-Light Insect Barrier - Super-Light Insect Barrier 8 ft x 20 ft Barrier
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Japanese Beetle Trap - Japanese Beetle Trap
Tackle nasty lawn grubs NOW—Beforethey cangrow up into Japanese beetles and other pests!
Q. Dear Mike - I am turning thefront yard into a garden (perennials and shrubs) - no more lawn mowing!In the process of trying to break through the clay I found lots ofgrubs. This probably explains why I had so many Japanese beetles lastsummer! My organic options seems to be nematodes, which look like theyneed to be applied each year, and a 'milky spore' that is said to lastten years or more. What do you recommend?
---Ellen, Esq. InWynnewood, PA
Hi, Mike. We moved into a new home, and have grubs by the ton!Literally every shovel full of dirt I turned over while putting in newflower beds last Fall unearthed at least a half dozen. I'll probably bemost inclined to take action if you tell me that they'll also devourthe roots of the flowers we're planting. Thank you, and keep up thegreat work!
---Vince in Coopersburg, PA
My lawn needs desperate help. My main problem is grubs - Japanesebeetle and Masked chafer are both present, and I have brown patches inthe lawn.
---Linda; New Stanton, Pennsylvania
A. "Desperate help"? Is thatlike "Desperate housewives"? Or just a reference to what kind ofassistance you expect here? Let's see how desperate we can get…
White grubs—ugly grayish-white crescent shaped creatures—are the larvalforms of a number of beetles. The best known is the Japanese beetle,but grubs can also be baby beetles of the May, June, Asiatic garden, orOriental variety; or Northern, Southern or European masked chafers. (http://ohioline.osu.edu/hyg-fact/2000/2505.html)
If you're game, you can identify your exact grubs by their distinctivehinders. Yes, only You Bet Your Garden could bring you a Universitypaper that will soon have you scrutinizing your nasty grubs' rearends—you just don't get this kind of service from other gardeningshows! Here's the link to Ohio State University's 'beetle-to-be hinderfinder': http://ohioline.osu.edu/hyg-fact/2000/2510.html. Have fun, kids!
The adults all have the same basic body type—the classic 'scarabbeetle'—and pretty much follow the same life cycle. Adults emerge inearly summer, copulate as they defoliate (most of 'em, that is—someadult beetles don't bother plants at all!) and then the females layeggs mid to late summer. Japanese beetle females only lay their eggs insod—so if those are the only grubs you have, your flower roots will besafe. But others, like May and June beetles, lay their eggs in plainold dirt, and their grubs will eat the roots of flowers and veggies.
Anyway, the eggs hatch quickly, the grubs feed on roots (grass formost, but ornamental plants for some), go through three fast molts andare about an inch long and eating a ton by Fall. When the weatherchills, they drop below the frost line, moving back up when the soilwarms in Spring.
Large numbers of grubs feeding in a lawn will cause brown patches thatlook like drought stress to appear in late summer. To make sure thatgrubs are the cause, lift up these dead areas when the pests are closeto the surface—in general, August and September in the Fall, and Apriland May in the Spring (as soon as soil temps reach 60 degrees). Gotgrubs? You have two good options to knock them out before beetles flythis season.
"The Spikes of Death" is the nickname a researcher gave thoselawn-aerating sandals you see in garden catalogs (just search the term"lawn aerating sandals" on the web). Now, these things don't aeratelawns—you need to pull up plugs of earth to do that; but they are theperfect length to spear grubs when the pests are close to the surface.Just walk overtop of your brown patches this Spring when a soilthermometer says the dirt is 60 degrees and you'll kill more grubs thanan insecticide. Same thing in the Fall. Be sure and think good thoughtsas you dance.
Beneficial nematodes are microscopic wormy little guys that come packedfive to 50 million in little sponges. You water them into a wet lawn ona warm evening and they work their way down below the soil line to preyon grubs. The members of a newer strain (Heterorhabditis species asopposed to the older Steinernema types; pay attention—there's going tobe a test after the show) are more aggressive and mobile, actuallygoing after the grubs as opposed to lurking in wait for them. When youbuy nematodes make sure their scientific name starts with an 'H', andnot an 'S'. (Gardens Alive "grub away" nematodes are the right species,and they offer two kinds—one for Southernlawns, and a 'Northern'variety that is active in cooler soils.)
Yes, you do need to reapply the nematodes every year (the same is truewith toxic insecticides, which you won't even consider using becauseyou're too smart to poison yourself, right?). You can release them inSpring or Fall. Or both if you need to control a really severe grubproblem. They won't harm good soil dwellers, like earthworms, but areeffective against some other lawn pests, AND they kill flea larvae inyour lawn, which makes Springtime release a really, really good idea iffleas have troubled you in the past. They are very cool little guys.
Milky spore disease is one of the oldest organic remedies. (Here's agreat scientific article about it: http://www.ag.uiuc.edu/cespubs/hyg/html/200120b.html;you can find it for sale at most large garden centers.) Apply it to alawn as directed once every summer three years in a row and it willbuild up enough disease spores in your turf to prevent grubs for adecade or two. But it doesn't have much effect the first couple ofyears, and it only works on Japanese beetle grubs. So check themhinders.
One of the most effective controls is to simply avoid watering yourlawn in the late summer egg-laying season; the eggs will die if theturf is dry. Don't chase starlings; these so-called 'pest' birds feedon the grub-babies in your lawn and adult beetles! Another greatnatural enemy is the Spring Tiphia wasp; the female goes down into thesoil and lays her eggs right on the pests, killing up to 85 percent ofthe grubs in a lawn—better than nasty chemical insecticides! Plantforsythia,peonies,and firethorn to attract these greatbeetle-killers; and don't kill what looks like winged carpenter antsvisiting those plants in the Spring; those are the wasps!
And finally, don't plant the adult beetle's favorite foods near lawnsif you can help it. With Japanese beetles, that means keeping the rosesaway, of course. With other types, it's fruittrees and shrubs.Checkthem grub hinders and then go look up what Mom and Dad like to eat.
You Bet Your Garden Question of the Week ©2005 Mike McGrath
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Japanese Beetle Trap
The Japanese Beetle Trap is a highly effective pheromone trap. This trap catches and confines more beetles than any other trap we've tested!
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Super-Light Insect Barrier
This lightweight row cover provides an excellent all-season insect shield. Translucent polypropylene fabric transmits 95% of sunlight but causes almost no heat buildup, so you can leave covers on all summer, without harming heat-sensitive plants.