Myrtle and overgrown grass - Ask Extension
I live in western Pennsylvania and recently built a stone patio. I surrounded the patio with about a foot wide area in which I planted Myrtle. Many ...
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Myrtle and overgrown grass #214598
Asked September 28, 2014, 1:50 PM EDT
I live in western Pennsylvania and recently built a stone patio. I surrounded the patio with about a foot wide area in which I planted Myrtle. Many of my neighbors have done the same. The Myrtle is overrun with grass. It looks like regular lawn grass. I tried to just pull the grass out but it comes back and the Myrtle is so dense and the grass so ubiquitous that this doesn't work for more than two weeks. I cannot find a spray chemical that would kill grass but not Myrtle. Do you know of anything that I can do?
Allegheny County Pennsylvania
Expert Response
The selective herbicides Vantage or Fusilade can be applied over the top of Vinca minor (myrtle) to kill grasses. Both products are very slow to work, but they will give excellent control. They are available from many commercial pesticide dealers.
Thanks, I saw other related questions with similar answers so I will try it. Do you think it is better to treat now or in the spring?
Our weather is turning colder this weekend and a heavy frost is possible. If the grasses in the periwinkle planting are annual grasses, they may be killed by a heavy frost. I would delay treating the periwinkle planting with Vantage or Fusilade until after there is new grass growth in the periwinkle bed next year. Also consider applying the pre-emergent herbicide trifluralin or Treflan to the periwinkle bed in March. The home and garden product Preen Garden Weed Preventer will not injure the periwinkle, but it will prevent annual grasses from germinating. Preen or Treflan should be applied prior to weed seed germination in the spring. Preen or Treflan should be watered in immediately after application for best results. Preen or Treflan should last about 6-8 weeks and can be reapplied to the site if needed.
