Strategize to Beat Weeds

by Marty Fisher, EMGV

I have a lovely patch of chocolate chip ajuga—it has dark purple evergreen leaves and blue flowers in early spring. It spreads stoloniferously and lately, it has begun to drift through my perennial bed, establishing small colonies in attractive drifts. It’s a nice companion to red and yellow pansies in the spring, fades away to let perennials shine in the summer, and provides a fluffy green and purple texture to brighten winter.

So, just imagine my horror this summer, when hundreds—I kid you not—hundreds of tiny, bright green weeds appeared woven throughout my ajuga like a rampant cancer.

chamberbitter — This is the dreaded chamber bitter, new to my garden this year. It’s also known as gripe weed, leaf flower, or little mimosa. It has yellow flowers on the underside of the leaves. If it’s nestled amongst your perennials as mine was, the only good solution is hand weeding, before it sets seeds and preferably when the ground is soft and wet.

Chocolate chip aguga … before infestation with chamber bitter.

There was nothing to be done but spend hours on my hands and knees painstakingly plucking the little suckers out one by one. I discovered the name of my new weed is chamberbitter, which sounded exotic enough to make me feel a little better. It looks a little like a mimosa and has yellow flowers under the leaves. It likely rode in on something I planted, or perhaps one of the many birds I feed graced me with it. I must have missed it last year, and it set seed and multiplied. It is now July, and I am still plucking at it, watering it with my sweat as I go.

This awful experience got me thinking about the strategies weeds use to get into our gardens, gain a foothold, and multiply. They have multiple methods of getting into our gardens—through birds’ digestive systems, in containers from nurseries, or they simply ride in on the wind! One source I consulted suggested removing the top layer of soil from nursery plant containers before planting. This seems like a good strategy, especially for the ubiquitous oxalis! But I can’t think of anything to stop the weed attack from birds or the air…

As happened with my ajuga, weeds like to mingle with existing plants—nestled as close to our favorite plants as possible. This provides protection and makes them harder to eradicate. They also are adept at snapping off when we try to pull them, leaving their roots intact to sprout again. For bigger weeds, I use a Japanese hori hori knife.

The knife can slice into the dirt just at the base of the weed, without disturbing the soil too much. Then you can grab it as close to the ground as possible and pull. Other valuable tools include an old table fork for twisting out the roots of weeds and a fishtail weeder for digging out tap-rooted or bulbous weeds such as dandelion, violets, or dock.

This may come as a shock, but every inch of your garden and mine is chock full of weed seeds. They can lie dormant for years, and all they need to germinate is a little light. When we dig, plant, or even hand weed, we bring weed seeds into the light. So, it’s critical to cover any exposed or disturbed soil with mulch. Two inches of mulch is recommended. More can cut off oxygen to the plants we love. Never skimp on mulch—I would skimp on fertilizer before I skimped on mulch!

The best time to pull weeds is before they set seed, and after a good soaking rain. Once weeds set seed, the battle is lost. You’ll be fighting them for years to come. After a rain, weeds come up easier with less disruption of the soil, and mulch applied after weeding will hold in the moisture from the rain. For really bad weed infestations, the best solution is spraying with glyphosate. But this is not an option in closely planted landscape beds, as glyphosate kills any plant it comes into contact with.

Never put freshly pulled weeds into the compost bin. Heat is the key to composting them. I find it very satisfying to lay them out on my asphalt driveway where I can watch them cook in the sun. Even after they are fully cooked, I’m not brave enough to put them in my compost bin, but sources say, once they are dead and rotting, you can put them in clear plastic bags, leave them in the sun for two or three days, then compost them. (I don’t now that I reallyneed compost all that much!)

We are all busy. It would be great if we could mulch at the best time and weed at the best time. But sooner or later, we all miss the ideal timing. I think weeds know this will happen, and they take full advantage of it. By nature, they are designed to grow and set seed rapidly, the better to evade the gardener and spread their offspring across the land. So, if you can’t get in to fully eradicate them, lop off their heads. This keeps them from setting seed until you can get back in the garden.

I am not sure I believe this, but according to soil scientists, fewer weed seeds germinate in soil that contains lots of compost and organic matter. But it can never hurt to enrich the soil, so good advice regardless! (My perennial bed is full of compost and organic matter, and I have plenty of weeds…just saying …)

My goal every year is to get everything planted, weeded, and mulched before we leave for the July 4^thholiday. Then I coast until time to plant winter veggies in early August. I wish everyone a weed-free summer!

So here is a rogues list of plants I have been fighting lately. Only because of its name, tops on my list is Hairy Crab Weed, or Mulberry weed. It is a monstrous weed and it has a distinct smell.

Then of course there is Japanese stilt grass, which is ruining the chances of survival for our native wildflowers. It loves shady woodland environments.

Nutsedge is another candidate for most obnoxious! The best weapon for this one is glyphosate but if it’s in your perennial bed, that’s not an option since the spray will kill your desirable plants. Nutsedge retains a “nut” or a seed, in the ground. After you pull it, it will re-sprout.

So, I guess the bottom line is, weeds are just something we are going to have to deal with. I don’t think you can completely eliminate them but if you set aside a day each month to pull them, you can keep them somewhat at bay. Happy Summer!