I would mulch lightly over the seeds and apply a good layer over the bulbs. In the wild, seeds push through all the detritus left from the previous year and bulbs will push through the mulch as long as it is not heavily compacted.
Hi Smokeybones, when you ask do you put mulch over the top of the bulbs /seeds, did you place soil on top of the bulbs after you put them into the soil.
All bulbs when planted need to be put in the soil to a depth 3 times the size of the bulbs, so a lily bulb say 3 inches from tip to root end, then you plant it 9 inches deep, or say a snow drop bulb half inch from tip to root end, then these go into soil i and half inch per bulb. then you cover them all with soil.
Depending on the type of bulbs /flowers, some bulbs require some extra drainage at the root area so I add a handful of horticultural grit to the bottom of the hole, some people add horticultural sand, you can buy this in small bags at garden stores, I also add a handful of blood/fish/bone meal and again you buy this already mixed from garden stores, none of these helpful products are more than a few dollars each but they are money well spent.
As for your seeds, IF you have a sieve for soil then I use that sprinkled over seeds outdoors or again, use sand if your unsure how much to cover seeds, always remember to water when needed, stick your finger into soil, if dry, water if damp don't. just make sure you dont use hosepipe with full blast or you will disturb the seeds that are trying to germinate and probable send them floating all over the wrong place.
Once seeds have grown 2 sets of true leaves, then you can gently dig them up with hand fork and transplant them out where you want them to grow on and flower.
Hope this is of some help to you and you enjoy all the fruits of your hard work.
Best of luck. WeeNel.