Re: Mosser's division questions
:When I dig and divide my other iris late this summer, should I also divide
:the new increases on the damaged rhizomes? If I do divide these, should I
:just separate them completely from each other, as well as, from any portion
:of last year's rhizome?
That's what I would do. There's no point in risking replanting partly
:When I divide bearded iris, should I remove last year's portion of the
:rhizome, regardless of how healthy it might be?
I always discard the old rhizome, unless the increases are very small.
If the new rhizomes are large an healthy, they don't need the food from
the old one, which may carry disease or be an invitation to rot.
:Should each new division get a portion of the old rhizome if it is healthy?
I might do this if the increases were very small, but otherwise
I'd just break or cut them off from the mother rhizome at the narrowest
part of the join.
:Does a healthy older portion of the rhizome store food for the rest of the
:plant and increase bloom on the newest increases?
I don't know if this has been studied scientifically. I think the
conventional wisdom is that once the new increase is full-size and mature--
which it usually will be by digging time--its own root system is so
well developed that it does not draw sustenance from the mother rhizome
any more. Anyone know more about this?
:In the same vein, does dividing too often delay or deter first bloom on new
Commercial growers routinely divide each year. This apparently produces
the strongest rhizomes most likely to bloom the next season. I think
the *quality *of bloom seems to be best on a two-year-old clump, but I
don't think frequent division reduces the quantity of bloom in any
way. In fact it may increase it.
:If the older portion of the rhizome is still healthy can I plant this
:separately in a pot to force dormant buds on the old rhizome and increase
:stock of favorite varieties?
Happy irising, Tom.
Tom Tadfor Little firstname.lastname@example.org -or- telp@Rt66.com
technical writer/editor Los Alamos National Laboratory
Telperion Productions http://www.rt66.com/~telp/