by Abiya Saeed, Extension Horticulture Associate Specialist II, Montana State University, abiya.saeed@montana.edu

Introduction

Dandelions, one of the most famous weedy plants, can be a bit of a polarizing subject: some love them, some hate them, but many often find themselves somewhere in the middle of this spectrum. Some people enjoy eating these infamous plants, while others embrace them as a source of nectar and pollen for pollinators in urban landscapes.

Dandelions

Yellow flower with green grass in the background

Dandelion in lawn. Photo: Abi Saeed, MSU

Dandelions (Genus: Taraxacum) are a widespread genus in the Aster family and contain 250 species worldwide.  The two species most common in Montana are T. officinale (common dandelion) and T. erythrospermum (red seeded dandelion). These species originate from Eurasia but have since become naturalized in many parts of the world, through intentional and unintentional introductions. Dandelions are short-lived perennial plants that can reproduce sexually (through seeds) and asexually (through the roots), can withstand a wide variety of climates and soil conditions, produce abundant seeds, and thrive in disturbed areas: all of which can contribute to the fact that dandelions are so prolific and widespread.

Managing Dandelions

Although some embrace the odd dandelion speckled in a lawn, large swaths of dandelions in the place of what used to be turfgrass is a problem that usually extends beyond dandelions themselves. One of the best ways to combat dandelions in a turf lawn setting is to make sure your turfgrass is healthy and able to form dense coverage on the soil. Healthy turf can often outcompete weeds that opportunistically take advantage of open spaces for establishment. Addressing soil compaction, nutrient needs, and responsibly caring for your turf lawn all play a role in reducing dandelions. For flower beds or vegetable gardens, mulches can be used to reduce dandelions. Mechanical removal is also very effective for controlling dandelions, depending on the scale of the issue. Using your favorite tap-root removal tool (such as the aptly named “dandelion fork”), you can remove plants without too much exertion. Pulling out as much of the root as possible will offer the best control, as dandelions are less likely to regenerate from smaller root fragments.

Several herbicide options are available for dandelion control. Two,4-D, dicamba, and MCPP (commonly found in  "weed and feed" products) can be effective in lawn settings. Spot-treating individual plants is usually more effective than broadcast application across larger areas. Herbicides with the active ingredient glyphosate are most effective for long-term control of dandelions if a plant is cut or mowed and the herbicide is carefully painted on the fresh cut, which can facilitate movement into the root system. Late summer and early fall are the best time to control dandelions. This is because these plants are moving resources from the foliage to the root system to prepare for winter, which can also help to transport systemic herbicides to their roots and/or deplete their root systems of energy for more effective and longer-lasting control. Spring management (before flowering and seed production) can also be effective. Always read and follow label directions, and if unsure, reach out to your Extension resources for assistance.

Further Information

For more information on dandelions (including as a food source for people and/or pollinators), check out the Garden Professors Blog post.

For more information about this month's weed post, contact Extension Invasive Plant Specialist Jane Mangold. Past posts are available in the Monthly Weed Post Directory.

THis weed post is also available as a printable PDF (130 KB).