

Weed Impede® herbicide is a preemergence surface-applied product for the control of many annual grasses and broadleaf weeds in ornamental plantings, rock gardens, ornamental bedding plants, bulbs, ground covers/perennials and established warm-season turfgrass.
Weed Impede® is orange in color and may cause temporary discoloration of sprayed surfaces.
What does Weed Impede do?
It is a preemergence product that prevents weeds in your landscape ornamental areas for up to 6 months.
What weeds does Weed Impede control?
Weed Impede® is primarily a grass killer, but it is quite active on broadleaf weeds such as pigweed, purslane, spurge, oxalis, and many others.
How much Weed Impede do I use?
The recommended rate of application is 1½-3 oz per 1000 sq ft. in sufficient water for coverage. 2 gallons of spray will cover approximately 1000 sq ft. For a 2 gallon sprayer, add 1½-3 oz of Weed Impede®, shake well, and spray.
Once Weed Impede has been sprayed, what do I do?
Weed Impede® must go into the soil to be effective. If you are in a high rainfall area, watering in is not needed. In other areas, water into the soil using sprinklers. You can wait up to 21 days to water-in, but the sooner it is done, the sooner it starts to control weeds.
Will Weed Impede control weeds that are already up?
No. If weeds already exist (and no ornamentals have been planted) they need to be controlled separately. Weed Impede® will go into the soil to prevent those that have not yet germinated.
How many times a year should I use Weed Impede?
Generally, twice a year. Once in the fall prior to the rainy period, and once again in the spring after the bedding plants are placed, depending on length of growing season.
What ornamental trees, plants, shrubs, or ground covers can I use Weed Impede on?
Over 175 species of ornamentals are on the Weed Impede® label. These include bedding plants, ground covers, shrubs and trees.
What species should I not use Weed Impede on?
Specifically, Weed Impede® should not be used on: slender deutzia, douglas fir, techny aborvitae, or eastern hemlock.
What is the best way to use Weed Impede on bedding plants?
The first step is to prepare the beds by rototilling, spading, etc. Plant the bedding plants and then spray Weed Impede® over the entire area. Once sprayed, turn on the sprinkler and wash the Weed Impede® into the soil.
Can Weed Impede be used in my vegetable garden?
No, Weed Impede® is only registered for use on ornamentals.
Can I use Weed Impede on bulbs?
Yes, Weed Impede® can be used on iris, daffodil, narcissus, gladiolus, hyacinth, and tulips. Application should be made 2-3 weeks after planting the bulbs, but prior to weed emergence. Do not use on gladiolus corms less than 1 inch in diameter, and do not apply to tulips that have emerged over ¾ inch.
Can I use it on turf for to prevent crabgrass?
Yes, but only on warm season turf species such as bermudagrass, st. augustine, buffalo-grass, bahiagrass, zoysiagrass, tall fescue, etc. Do not use on cool season grasses such as bluegrass, ryegrass, bentgrass, etc. Apply only to well-established turf.
Note: Do not plan to overseed for at least 90-120 days following application.
Can I use Weed Impede on tall fescue turf?
Yes, but use it very carefully. Do not apply at the single application rate! Apply Weed Impede at a rate of 1 oz per 1000 sq ft. in the initial application, followed by 1 oz per 1000 sq ft., 8-10 weeks later. Do not treat tall fescue in the spring or summers if it was seeded the previous fall. Weed Impede® can only be used on well-established tall fescue, and then carefully as outlined above.
Will Weed Impede stain?
Yes. Weed Impede® will cause a bright orange stain on rocks, sidewalks, etc. To avoid this temporary stain, wash the material into the soil immediately after application, before it dries.
What rates do I use Weed Impede on warm season turf grasses?
Apply to well-establish turf one time in the spring, prior to crabgrass germination, at 1½ oz per 1000 sq ft.
Are there any special instructions for usage on tall fescue?
Yes. On well-established tall fescue, apply an initial application prior to crabgrass germination at 1oz per 1000 sq ft. Follow with a second application of 1 oz per 1000 sq ft., 8 to 10 weeks later.
Can I cultivate or hoe the flowerbeds once I have applied Weed Impede?
Yes. Once it has been watered into the soil, additional cultivation does not decrease the weed control.
Soil Preparation:
Weed Impede® controls weeds growing from seed. Weed Impede® will not control emerged weeds. It does not control established weeds, weeds growing from stolens, rhizomes, or root pieces. Therefore, areas to be treated should be freeof emerged weeds. Weed residues, pruning and trash should be thoroughly mixed into the soil or removed prior to treatment.