Perennials - Weeds
Back to Perennials

  What can I use to kill saw briers in my flower beds? We have been here for five years and I have been battling these with everything I can buy at the feed store. So far, I haven’t won the battle.

  Saw briers are difficult weeds to kill. The vines get almost woody in growth habit. Try cutting out or pulling out all that you can. As young vines emerge, spot spray with a glyphosate product, such as Round-up. One application won’t do it, so spot spray several times throughout the growing season, taking care to avoid getting any of the spray on your desirable flowers. Pay particular attention to spraying in late August and early September. As these perennial weeds prepare to go dormant they send more nourishment to the root system and will also send more herbicide then.

  I am enclosing a picture of a plant that we have been using in our back yard for several years. It winter kills, but comes back strong every spring. It will get as high as 10 or 12 feet and has a very heavy seed head. It is a very graceful plant, and we sit on our patio and enjoy watching it when the wind blows. We live by the golf course in Jacksonville, and when people ask us what kind of plant it is, I have to tell them I don’t know. We hope you can name it.

  The plant in question is a common weed called dog fennel, Eupatorium capillifolium. It forms a large clump of delicate looking ferny fronds. It makes an attractive backdrop for other plants, but it can freely reseed in other areas. It is a tough plant, so learn to recognize errant seedlings and enjoy your native plant. They should come back each year from the root system, and will usually form a slightly larger clump each year.

  Is there a herbicide that will kill the grass in my flower beds but not hurt the bulbs and roses?

  There are several herbicides labeled specifically for grass control in flower beds which won’t damage the bulbs or roses, however, it is too late for them this season. Poast, Fusilade, Grass-b-gone, and Over the top are several trade names. They are best applied in early to late June, when the grass is beginning to take over. It works best on actively growing grass. Most grasses are going dormant now for the winter. Plus, you would still have dead grass to look at once it is killed. For now, try to hand weed, and be prepared next spring and summer.

  I have a flower bed with mums and several other perennials that doesn’t look good. I was writing it off to the heat, and I have to admit, I haven’t been too diligent about weeding this season either. The other day I noticed some type of vine has completely entangled the plants. It is almost like wire. It is turning and orangish yellow in color. What in the world is this, and what should I do to control it? 

  It sounds like you have been attacked by love vine, or dodder. This annual weed is actually a parasite. It germinates from seed (which may be on your vine now), then it attaches itself to the host plant, and takes all its nourishment from the host. You will no longer be able to see any root system or method of attachment to the soil. This weed is very aggressive, and if it is allowed to set seeds now, it will come back next year. Pull up the plants that are entangled, and sacrifice them to the cause. There is no way you can eradicate vines without losing the plants they are in. Next spring, consider using a pre-emergent herbicide in this bed to prevent the seedlings emergence.

  What can I do to rid my flower beds of wild strawberries? The long creepers have invaded the entire area where I plant flowers, bulbs and herbs. I feed I should be doing something now to destroy them before they get a foothold this spring.

  If the strawberries are green and growing now, and your flowers aren’t, you could spray with a glyphosate product such as Round-up. Spot spray just what you want to kill. While the area is more workable (with less foliage and plants growing) you might also get in there with a hoe and try to weed out as many crowns and runners as you can. While you probably won’t get all of them at one weeding, you should start a lot cleaner and hopefully keep the problem controlled. Wild strawberries are a hard weed to control, and since they are perennila, pre-emergent products won’t give you any control at all. Monitor your beds often this spring, to keep them in check.

Back to Perennials