Gardening: Prevention best plan of attack for weeds

Our spring is at least three to four weeks early at the moment. I have peonies and iris ready to open that don’t usually pop until the first week of June. The lilacs are done and we are still two weeks out from the Lilac Festival. I couldn’t spray my cherry tree for fruit worms because the apples were blooming right on top of it and I didn’t want to harm the bees.

The weeds are also three weeks early. I have never seen bitter cress, the early weed that flings seeds everywhere when you touch it, competing with warm season mallow and prickly lettuce. I’ve been inundated with these obnoxious plants and am having a hard time staying on top of them. I have precious little time to play in my garden as it is, and I’d rather not spend it weeding.

My garden could be much worse than it is, though. A couple of years ago I started a pre-emptive process to reduce the amount of time I spent weeding by planning ahead. My philosophy now is that if I can beat them before they start I might win this challenge.

Last fall, I did a very thorough weeding of a couple of the beds with the worst problems and then laid down a shredded pine needle mulch created from the falling needles. My perennials were still visible so I just packed mulch around them about 2 inches deep; no bare dirt in sight and no weeds this spring.

Orchard or quack grass has always been a challenge in my beds. It’s long white roots travel far and wide, always coming up where they aren’t wanted. While the grass was still growing in September, I mixed a small batch of glyphosate in a container, dipped a cotton glove in the mix and wiped it on the grass blades, being careful not to drip it on the good plants. The grass dies and your plants remain. I put a plastic glove on under the cotton one to protect my hand.

In other areas, I weeded heavily, but they didn’t have a lot of ornamental plants. I laid down porous weed-blocking fabric and then covered it with mulch. This will help cut off the seed supply that reseeds into nearby beds. The fabric allows air and water into the ground, but is dark, so it blocks light from getting to the weeds.

Lastly, I judiciously used weed-blocking, pre-emergent herbicides that help control weeds in my gravel patios and driveway. Depending on the chemical, they can prevent weed growth for six to eight months. Some of the herbicides also have a component that will kill standing weeds. Always read the label on the bottle carefully and pay particular attention to warnings about keeping the spray outside the drip lines of trees. Some of the chemicals can be easily picked up by tree roots with disastrous results.

Pat Munts is the co-author, with Susan Mulvihill, of Northwest Gardener’s Handbook. Munts can be reached at pat@inlandnw gardening.com.