Answer: In general, a flower bed does best with only a few inches of organic mulch, two inches or so should be fine for summer. This amount of mulch would not prevent bulbs from coming up through it. (I am not sure what context you would have read about not mulching over top of the bulbs.) When mulching, do not apply the mulch over top of the crowns of plants or foliage or emerged bulbs that are already growing -- the mulch should never cover or touch the plants. After mulching, you could use whatever weed preventer according to the label instructions. You may also find that old established weeds come back up again from their roots. These may be smothered or spot treated with an herbicide containing glyphosate. Be careful to read and follow the label directions very carefully as this herbicide will kill desirable plants as well as weeds.
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