Answer: Bedstraw is such a prolific weed that it can take over in just a season or two. For complete eradication, you may have to dig the bed, remove your bulbs and rhizomes, and hand pull the bedstraw. Then you'll have a nice, clean bed to replant in. Your iris and narcissus will need to be dug and divided eventually, anyway, so why not take care of all the problems at once? If you'd prefer to use an herbicide, try Safer's Sharp Shooter. It's fairly thorough if the entire weed is saturated. Be sure to read and follow the label directions. You can keep ahead of the weed invasion if you keep the weeds pulled when they're small, before they have a chance to flower and set seeds.
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