MAKING THE CROSS... applying pollen to the stigma. Best results are with freshly opened flowers. The stigmatic lip may be slighty stuck to the style crest on very fresh flowers. Encourage it to stand out by gently pulling back on the top of the style crest. Notice the pollen I have applied to the stigma in the photo. I fertilize all three stigmas of each flower. One anther may do all three, but if you have plenty of pollen, use a fresh anther for each. Only a little pollen is needed... one grain of pollen will fertilize one seed, but I prefer to apply liberaly. After a few crosses you will get a good feel for it, and be able to conserve pollen that may be in limited supply. You can hold the anther with tweezers if you prefer. You can also snap off the standards if they are in your way. Some folks snap off the falls to prevent insects from landing and adding foreign pollen to their cross. Insect pollinated flowers (bee pods) is uncommon. If you have been growing irises for awhile and have never seen a bee pod on one of your plants, chances are you have nothing to worry about.
PLEASE NOTE: Some varieties may not be fertile, either as a pod or pollen parent. Most are, but if you are having trouble with a particular cross, that could be the problem. I keep a list of every cross I make by date pollinated and parents. Depending on your needs, you may want to track weather conditions, time of day cross was made, age of flower etc. It helps keep up with successful and failed crosses, giving you some guidance in the future.
SUGGESTION: Remove all three anthers from the pod parent before you pollinate.