Best weed killer for new gardens?

Asked May 7, 2019, 2:09 PM EDT

We will be planing a new flowerbed in a week and want to use a spot weed killer to kill some grass sprigs and other weeds that are just sprouting. What do you recommend?

Multnomah County Oregon

1 Response

Thank you for using Ask an Expert for help with weed control in your flower bed.

There are several kinds of weed controls to choose from. Little sprouts coming up from seeds left over from years past are easily killed by a “top kill” choice. These products only kill the leaves above ground, but the seedlings are unlikely to come back because they are so weakened. Many of these products are made from essential oils (orange oil, clove oil, etc.) or are fatty acid-based. Use them carefully. Top kill products will damage the leaves of any shrubs or perennial flowers they touch, however the plant will probably not be killed.

Using those products against perennial or deep-rooted weeds (dandelions, quackgrass, clover, etc.) is less successful. Their roots store a good deal of energy, and they will likely grow back. For these weeds, a systemic weed killer—one that moves into the root system—can be the answer. Two common ones are glyphosate-based products and iron-based ones.

Whichever weed control you choose, be sure to read and follow all directions and cautions.

Consider that no matter what you use, weeds will be back—whether from seeds remaining in the soil or dropped by passing critters. Shading out the soil by close planting or maintaining a thick mulch will help keep weeds down in ornamental beds, as well as a watchful eye and quick action.

Have a good gardening year,