I fished Rocky Ford yesterday from about 1:30 until 5:30pm. This is not a place that I fish very frequently, so I cannot say that I know its "secrets" or understand the hatches, feeding tendencies of the fish, most effective patterns, etc. as others who fish it more frequently than I, but due to circumstance I have fished it twice in the last week and I can tell you that location wise, the most productive sections of the creek for me were below the first and third parking lots. These two sections produced fairly well for me as I was sight fishing rather than stripping streamers in the wider slower sections. Streamers (leeches, buggers, etc.) can be very effective here, especially since there have been so many people fishing the creek and this method allows you to target fish out in the wider sections away from the bank areas. The fish near the edges can become very edgy and selective. I did fish streamers yesterday for a total of 15-20 minutes and hooked two fish for what it is worth.
There was a fairly good hatch of small (20-22) black adult midges coming off during the early afternoon hours when the sun was up and it was fairly warm. Few fish seemed to take notice of the adults, but there were intermittent riseforms which indicated that the fish were taking what likely were the emergers or pupa just under the surface. Midge pupa patterns can be effective here, and a small 18-22 red bloodworm pattern has worked well for me at times in the narrow section of the creek below the third parking lot. In the "faster" sections small pheasant tails (20-22), barr's emerger's, copper john's, brassies can also produce at times. I would say to be very flexible in your pattern selection and do not get married to any one fly (unless of course you find that it is THE fly that the fish cannot resist, but even then the fish will turn off that pattern likely sooner than later).
Yesterday, the pattern that was most productive for me was a size 14-16 pale orange scud. Scuds are readily available to fish and these patterns are always a good bet on this creek. After you make a decision on what color you want to fish (olive, orange, pink have been effective here for me), if you get refusals repeatedly than I always immediately go down a size in the same color. Smaller flies are very effective here, but with that do not be afraid to use a larger scud (10-12) if you get no response from the fish to smaller sized flies. I have no theory on why this is, but some days the fish will only take the larger scud and refuse smaller ones.
Egg patterns also work well here (I think the fish take them as scuds). Pale orange and pink egg patterns also caught fish yesterday for me.
Anyhow, good luck and report back on how you fared.