Herbicides for Silverleaf Nightshade

Effective Herbicides

• Picloram (commercially named Tordon 75-D), fluroxypyr, (commercially named Starane), and glyphosate (listed under various trade names) are effective in controlling silverleaf nightshade. Keep in mind that while glyphosate herbicides are generally cheaper than picloram and more effective than fluroxypyr, glyphosate is a non-selective herbicide. This means that it will kill everything it touches, including desirable plants and grasses.

Application

• Herbicides can be spread using a spot spray technique. This means plants are sprayed until they are wet, but not dripping. When dealing with large or scattered populations, it may not be practical to hand spray each plant. Other application equipment options include boomsprays and wick wipers.

Timing

• Herbicides can be applied at several times throughout the silverleaf nightshade growing season depending on the desired outcome. Herbicides applied at flowering, generally mid-summer, will prevent berry and seed production. Herbicides applied at the vegetative growth stage, generally spring or autumn, provide the best opportunity for the herbicide to seep into the roots.

Alternative Control Methods

• Silverleaf nightshade has the ability to regenerate from root fragments. Thus, while careful hand-pulling may be effective, roto-tilling may actually make the problem worse. Ground covers, such as ivy, juniper, honeysuckle, gazania and periwinkle, can help control silverleaf nightshade by not allowing silverleaf nightshade to get the nutrients, sunlight, water and space it needs to thrive. Finally, the fungi Verticillium dahliai has been identified as having the potential to kill isolated silverleaf nightshade plants but is not considered to be a practical option for large populations of silverleaf nightshade.