Pesky plants and persistent herbicides

Imagine this: you've worked the dirt, put in a few seeds, a few more transplants, water regularly, and everything in your garden is going along swimmingly. You decide to give it all the nutrient rich reward of top dressing with compost and bam! It all droops, leaves start curling, and growth stops. Some plants even die.

What the hey?!? It could be you have a case of persistent herbicide. What's a persistent herbicide, you ask? It's when an herbicide, designed to target certain plants, hangs around the plant party well after everyone else has gone home. It maintains its active chemical form in the soil, in the plants it doesn't target, and even in rainwater and dew. It sticks around through the composting process. Yep, even hot batches of compost--it doesn't "burn" off like some other chemicals.

My garden, mulched with free grass clippings.

I'm not really here to write a long-winded, gloomy post about chemical residue (I've already done that) but just thought a warning was in place since I'm a big proponent of taking free organic matter from your neighbors. Commonly the worst offending chemicals are available to professionals, but keep in mind they're considered safe for pasture land. Since they're persistent (and I mean persistent) the chemicals remain active through the complex digestive system of cows and come out remaining as effective in cattle pee and poop.

Also, Scotts Miracle Gro will soon include Imprelis in some of their consumer grade products. Imprelis is one of those persistent herbicides that can take anywhere from 30 days to several years to break down. Bottles will warn consumers not to compost matter treated with the herbicide, but I for one, am a label skimmer and wonder just how many people will read the label.

Squash leaf curl, possibly from persistent herbicide residue.Image from Flying Tomato Farm.

What can you do to prevent herbicide heartbreak? Be an informed freegan! Read up! When scouting bags of leaves and grass clippings, skip over yards that look a little too green and a little too uniform in texture. Lots of times you can find free, composted horse and cow manure on Craigslist. If you're getting some, ask the farmer ask a few questions: Was the pasture treated with anything that contains picloram, clopyralid, or aminopyralid? Was their feed hay treated with any persistent herbicides? How long has the manure been composted?

Need to get rid of some weeds of your own? There are some pre-emergent treatments for lawns made from corn byproducts. Try one of those out as a chem-free solution. If you have a small area that needs weeding but don't want to get your hands in it, boiling water poured right on the leaves usually works for me. If you have a bigger area try a salt and vinegar solution. Mmm, tasty, now I want potato chips.

Do weeds in the grass bother you? How do you handle them? Any run-ins with a bad batch of compost? Any other burning plant questions? Comment away! I love to hear your gardening thoughts!

Renee Garner has a passion to make things grow, although her brownish thumb wants her to believe otherwise.  When mud pies aren't on the menu, you can find her doodling the days away at Wolfie and the Sneak.

Comments

[Valerie]

We've been using corn gluten meal to gradually change the pH of our lawn. It acts as a natural weed suppressant without harming the lawn. (Plus I like to think it gives farmers an alternative use than turning their product into tons of corn syrup)

[Cori]

Yes! Boiling or hot water works to kill weeds - I found this out by accident when I watered my mint with a hose that was left out in the sun. Thankfully mint is so persistent, it eventually recovered :)