Weeds in a flower bed present a unique challenge in that whatever method you use to kill them must not harm any of the nearby flowers. This means that non-selective herbicides should not be used, as these weed controlling chemicals will kill anything they come in contact with. A better way to kill weeds in a flower bed is to target each weed individually. This will take more time, but it will save your blooming plants and the end result will be a beautiful bed of colorful, thriving flowers.
Pull up the weeds by hand early in the season before they have a chance to set seeds. Protect your skin with gardening gloves, and use a trowel to dig up as much of each weed's root as you can. For weeds with tap roots, such as dandelions, use a fishhook tool to get under the full root and lift it out.
Place each weed gently into a trash bag. Try not to handle the weeds too much, as this can cause seeds to scatter back into the soil of your flower bed.
Add two to four layers of organic or synthetic mulch to the flower bed. Not only will this keep the flowers cool in the summer, but this will discourage any leftover weed seeds from germinating.