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Plant Doctor Archive
Unsightly irises
PLEASE
could you help me? Three years ago I was given some iris tubers.
They have grown very tall and produce beautiful white flowers for
quite a short time, then I am left with a mass of rather unsightly
tall leaves. They get blown around in the wind and also take up
too much room. I do like the flowers in their season, though. Can
they be cut down to say 20 cm until next year or should I lift
them out altogether? If I lift them, when should I plant them
again?
UNFORTUNATELY, irises are only
short-lived flowers, but worth the effort. When bulbs have
finished flowering, food is taken from the leaves and stored in
the bulb for the next season’s flowering. If you reduce the
foliage, you reduce the size of the bulb, which affects next
season’s flowering. The foliage can be cut back a little, by say a
third, although I would avoid doing this if possible.
Are these bearded irises or Dutch/Spanish irises? If they are Dutch/Spanish irises, just bend the foliage over and tie with a rubber band until the foliage has browned off and can be removed. This should hide unsightly foliage.
If they are bearded irises, I wouldn’t cut the foliage. Divide bearded irises every 3–4 years, which may help. Foliage can be cut back when dividing bearded irises. Replant straight away.
A clever way to hide foliage is to plant around bulbs so that annuals or perennials are coming up to hide the foliage as it dies down.
Yes, Dutch/Spanish irises can be lifted and stored in a cool, dry place with the foliage intact until it browns and dries off. Remove the dead foliage and store the bulbs in a net bag or stocking in a cool, dry place. Replant in autumn.


