Dandelions cannot be prevented.  A perennial dicot [broadleaf] weed, dandelions are most effectively controlled with a post-emergent weed spray.  Available at all garden centers, nurseries and big box stores, there are a variety of products registered for the control of dandelion and a host of other broadleaf weeds.

Weeds should be sprayed when actively growing and first noticed.  Spray should be applied so that the leaves are coated but not soaked. If it rains within the first 10-12 hours after treatment, repeat application.  Allow 3-5 days for leaves to curl and 3-4 weeks for the material to be translocated to the plant root for complete weed control.

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