Answer: Since you have bulbs in the ground, you probably don't want to use an herbicide that might affect them by penetrating the soil and moving with irrigation or rainwater. I think a safe approach is a contact herbicide such as RoundUp, which kills on contact and does not translocate in the soil. Or, you can simply starve the grass and weeds out by laying several thicknesses of newspaper over the bed and covering that with 2-3 inches of organic mulch. By the fall the weeds and grasses should be dead and you can rake away the remaining paper and organic mulch so the bulbs can sprout in the spring.
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