How can I control weeds in my raspberries?

Weed control in raspberries and other bramble patches can be labor intensive.  Persistence is important to prevent weeds from getting out of control.  Cultivation and mulches are the most practical weed control measures for home gardeners. 

Cultivation & Hand-pulling

Cultivate the raspberry plantings frequently during spring and summer.  To prevent injury to the roots of the raspberry plants, don’t cultivate deeper than 2 to 3 inches. If weeds are larger, hand-pulling is an option.  Be sure to remove weeds before they bloom and set seed.  

Mulches

Mulches help to control weeds and conserve soil moisture.  Possible mulching materials include straw, shredded leaves, lawn clippings, crushed corncobs, sawdust, and wood chips.  The depth of the mulch needed depends upon the material.  The depth ranges from 3 to 4 inches for fine materials, such as sawdust, to 8 to 10 inches for straw.  Since mulches gradually decompose, apply additional material each year.  Avoid mulching poorly drained soils to discourage root diseases. 

Herbicides

There are no selective herbicide controls available to home gardeners for weeds in raspberry patches.  There are a few ways you could utilize herbicides to reduce the need for cultivation and mulches, but chemical controls are rarely effective when used alone. 
The use of a pre-emergent herbicide will prevent new weeds from germinating.  Select an herbicide labeled for use on edible crops like raspberry.  A pre-emergent herbicide will not control perennial weeds already growing in the raspberry patch.  For those weeds, use a non-selective herbicide like glyphosate (Round-Up®) and carefully apply with a wick applicator. Make sure to avoid all contact of the herbicide with the raspberry plants.  Wet only the leaves of the weeds and not the canes or leaves of the raspberries. Always use all herbicides as directed on the label.