The careful use of certain herbicides around raspberry plantings can help keep weeds under control. Eradicating or suppressing weeds reduces competition for water and nutrients and helps raspberry canes perform better. Fewer weeds also make harvesting easier and improves air circulation through raspberry plants, which can reduce the risk of disease. Several herbicides are available for use around raspberries that help to manage both pre- or post-emergent weeds.
Glyphosate
Glyphosate is a good choice for treating areas where raspberries are to be planted to kill any existing weeds or as a pre-emergent treatment. Because glyphosate degrades quickly, you can plant raspberries soon after treating the area with this herbicide. According to Cornell University, once raspberries are established, treat post-emergent weeds with glyphosate using a wick applicator to prevent exposing raspberries to the herbicide. Not only will raspberry canes that come in direct contact with glyphosate die, but the herbicide will travel through the root system and kill adjacent canes.
Diuron and Simazine
Also known as Karmex DF or Direx 80DF, diuron is good as a pre-emergent herbicide for controlling weeds around raspberry plantings. It is particularly effective at handling chickweed, pigweed and most grasses. The Washington State University Extension recommends either a single winter treatment in raspberry rows or a split treatment in fall and spring. Simazine, trade name Princep, is another pre-emergent herbicide that is commonly used in rotation with Diuron. This treatment method helps to control weeds more broadly. What one herbicide does not kill, the other generally does.
Paraquat
The University of California Statewide Intergrated Pest Management Program states that paraquat, sold as Gramoxone Extra, works well on both pre- and post- emergent weeds. A late fall application after canes have died back or an early spring application applied prior to the raspberry canes emerging will help control most problem weeds. Do not apply this broad spectrum herbicide while green canes are growing to avoid damage to young raspberry plants. Use paraquat cautiously around established, mature crops when controlling new cane, or primocane, growth to avoid drift exposure.
Carfentrazone
Carfentrazone is commercially available under the trade name Shark and is applied in a similar manner as paraquat. This herbicide is effective to manage both weeds and primocane growth in established raspberry rows. As with paraquat, use carfentrazone with care around mature raspberry plantings to avoid drift of the herbicide into the upper canopy to avoid injuring foliage.
Fluazifop-p and Clethodim
To suppress grasses around raspberries, use a more selective herbicide, such as clethodim, sold as Envoy or Prism, or fluazifop-p, trademarked as Fusilade DX, Grass-B-Gon or Ornamec. These herbicides are specifically formulated to control a wide range of both annual and perennial grasses, including quackgrass, which is often difficult to eradicate with other herbicides.
Member Comments