I'm thinking of adding Blue Flag to my pond that is under construction now. Will it actually grow into the water and how deep? Is it easy to control? If i just want small patches here and there; how many plants should I put in a grouping?
Thanks

Blue flag the native Iris versicolor does not spread very fast and does not grow very tall. One plant may make 4 to maybe 5 plants in 2-3 yrs when growing in hard compacted pond basins. It will grow into about 6" to maybe 10" of water and can withstand the soil drying out in mid-summer, but it likes its feet wet in spring. Easy to control with glyphosate pond approved herbicides such as Shore-Klear Plus. But based on my experience with them you will never have to kill them off. However the yellow wet loving flag, Iris pseudachorus is a much faster spreader and grows 2 -3 times taller. The number of plants to introduce will depend on how "big" or expansive you want the small patches to be. After working with them for over 20 yrs and your stated goals, I suggest planting groupings of 8-16 one ft apart at the water line or in water 3"-6" deep. If you can find copper iris Iris fulva plant some of those in addition to the blue flag. They are similar growers with burgundy flowers.

FWIW, I have some at my pond. If you come over this coming Saturday you can see for yourself. I planted them 3-4 years ago. Last year they never got their feet "wet" but this year they have been in up to 6" of water.
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