I did some crosses the other day and placed small plastic bags over the emasculated flowers and snipped the corners out to allow moisture to escape. The bag is not tightly closed around the base to allow air in. Despite this I am getting a fair amount of condensation building up in the bags. Will this affect the chances of success? I can repeat the crosses without too much trouble but won’t if it makes no difference.
Simon,
You just described how I do all of my crosses, 100% of the time, and I have no problem with hip set (although, I do secure my baggies at the base with a twist tie). In fact, sometimes I actually suspect that it helps. However, I will admit that I have no scientific study/evidence to back that up…it is just a hunch based on my success rates. I tend to get a very high percentage of hip set with this process so I have never questioned it being detrimental.
BTW, I initially started using this process to protect my crosses from rain that might happen shortly after I made the crosses (it was a very rainy season the year I started doing this). Eventually, I just started doing it all the time, and I haven’t changed the process since. I have even made crosses while it was raining (not a downpour mind you, but a steady drizzle)and had excellent hip set with this process.
This is sort of one of those things that since it is working for me…why would I change it. 
)
Michelle
Thankyou for your reply Michelle 
I did this because this time of year is extremely windy here and my windbreaks have not grown in yet. I figured there is that much pollen floating around in the air, and I have loads of honey bees and bumble bees (and every other insect imaginable) that I couldn’t be sure what was pollinating what so I covered them up. It’s been nearly a week since I did the cross so I could probably remove the bag now.
Simon,
I used to remove my baggies about 2-3 days after pollination. Now, sometimes I leave them on during the whole time the hip is developing. However, I leave the bags in place now to keep the deer from eating the hips. So, I suppose, my baggies have become multi-functional at this point. LOL
We have no deer here (Australia) but I do get Wallabies in the yard. Their paws are quite dextrous and they just pull bags and the like off to get at what they want… so now I rely on the dog to keep the critters away.