If these are annual flower beds you just need to remove any dead plants and shovel or till in some good compost. Consider planting perennials, though, and your life will be easier down the road. If you aren't using drip irrigation in the beds, consider adding it.
If your in the drought area, if I were you, get out every evening - tonight thru Wed. and water the bed. Do it by hand, if possibe...let it soak in well.
Let the bed mellow (no water - Th&Fr), then plant your little ones.
Might as well give 'em a running chance in this dry spell. IMO