It's time to feed your lawn and prevent weeds with corn gluten meal
Chris in Gaithersburg, Md., gets a gold star for reminding me of an important "event." He writes: "I know we are approaching the time of year when you suggest putting a second corn gluten meal feeding down on our lawns. Is there a rule of thumb we can use to help us decide the best time to do so? Like the soil temperature rule of thumb you use in the spring?"
Chris, you're the best. Without your nudge, I might not have remembered this important opportunity in time to maximize its effectiveness.
As we reported for the first time last season, Dr. Nick Christians of Iowa State University has found that a well-timed late summer feeding with corn gluten meal can prevent weeds whose seeds germinate at the end of August, like dandelion, clover, plantain, henbit and common chickweed.
The ideal timing, says Dr. Christians, is right after the worst of the summer heat abates, which really doesn't apply to this weird weather season. Luckily, he also specifies a date-around Aug. 15 when the summer heat doesn't follow its usual pattern. So get your corn gluten ready, the ideal time to spread it is between now and next weekend.
Getting the most from your gluten
Chris in Gaithersburg reminds us that a late August feeding with corn gluten meal will provide the essential slow-release nitrogen your lawn craves for its fall feeding and prevent weeds that would otherwise sprout over the next few weeks, like chickweed, dandelion and clover.
To get the best results, spread 10 pounds of a corn gluten meal product that's labeled for use on lawns (don't use chicken feed) per 1,000-square-feet of turf anytime over the next two weeks. You'll get the best weed prevention when the corn gluten is soaked well with water immediately after application and is then allowed to stay dry for five to seven days. So try not to spread it right before an extended rainy period.
What about feeding, weeding and seeding?
Because corn gluten prevents all seeds from sprouting (just like chemical pre- emergents), you can't overseed your lawn right after the gluten goes down. (Well, you can -- but no grass will come up.) But lawns that are predominantly fescue need to be oversown with matching seed every couple of seasons -- always in the fall -- to stay nice and full. That's because fescues are clumping grasses that don't spread to fill in their own bare spots, the way bluegrass does.
So, if you want both weed prevention and the ability to sow more seed, you have two choices:
- Sow the grass seed ASAP and apply the corn gluten about two weeks after all of the new grass has germinated. Or,
- Get the corn gluten down ASAP, soak it well, and then mark a date six weeks from then on your calendar. Corn gluten's pre-emergent herbicidal action lasts for about six weeks, which allows you just enough time for it to wear off and make sowing some new seed safe at the end of September, which is still within the ideal window for sowing new seed.
But don't delay. If you can't do either right away, choose which is more important.
If your lawn looks mostly nice and full, use the corn gluten and wait until next fall to overseed. If you have a lot of bare spots and you know the grass is mostly fescue, spread matching seed and use a different organic fertilizer this fall. (Apply the fertilizer about two weeks after the new grass is up and growing. Don't fertilize when you seed.)
She's got wasps in her windows
A WTOP.com reader, username Dakota Rose Paris, left a plaintive plea in the comments section of the Garden Plot regarding our recent bit on yellowjackets. "My wasps aren't in the ground," she writes. "They've nested in a crack in the sill of my window. They are mean, they sting, and the sting welts up and lasts for days. How can I get rid of the nasty things without setting fire to the house?"
That's easy, DK. Get a big can of no-stick cooking oil spray, like PAM, and approach the area slowly, spraying any visible wasps as you go. Have someone else carefully open the window, while you spray any wasps that emerge. Do this when the weather is cool and the wasps will be moving more slowly. Then thoroughly soak any nests you see with the spray. Really saturate them.
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